Charles E. Roop giving his own forecasts, weather discussions, photos and adventures for the Starkville, MS area, Florida, and beyond.

Monday, October 24, 2011

Hurricane Rina Forms in the Caribbean Sea

I got my slight dose of shock this afternoon as Tropical Storm Rina was upgraded to hurricane status Monday afternoon. I say slight because it just looked really nice on the GOES loops.

Sunday afternoon, a tropical disturbance over the Caribbean Sea that was given invest classification became a tropical depression. Rina was then born by the 11 p.m. ET advisory.

When I viewed the satellite imagery this morning, the tropical cyclone (TC) looked like it was getting its act together quickly. The NHC forecasts had Rina becoming a hurricane a few days out. But the satellite loops showed Rina having good outflow and looking really organized. It wasn't until early this afternoon when USAF Hurricane Hunters found a central pressure of 991 mb and winds of at least 65 knots. This storm's winds increased 30 mph in roughly three hours and dropped 10 mb within the same time frame. At that point, the visible satellite loops were showing what looked like a developing eye.

Currently, the storm is still maintaining 65-kt winds. The pressure has dropped, but only a little (currently 989 mb) and the TC is still dragging west-northwest at 3 mph. Based on infrared satellite imagery, Rina's cloudtops are starting to become taller near the center of circulation (see below).

Source: NOAA
The ridge over southern Texas and northern Mexico is keeping Rina at bay and moving it slowly west. The GFS appears to break down the ridge come Tuesday afternoon as a trough over the western US begins to dig and move eastward. Most of the guidance models track Rina to the north and northeast late in the week. The NHC however, according to their last discussion, are not confident in the future track due to inconstant paths in the previous runs (hence why the "cone of error" is so large).

It may go north over time, but if it does, it may not last very long as a TC. The upper-level environment is very unfavorable to the north of Rina. Current wind shear numbers are 30+ knots. The NHC expects southerly shear to begin impacting the storm within a few days. Dry air is parked to the northwest of the storm. Right now, Rina is doing a good job of shielding itself from this dry air. But once it finds a way in, Rina will start to deteriorate. If, for example, Rina does move towards Florida, it will likely not be a beast of a hurricane because of this. Heck, it'll likely not even be tropical in nature at that point. It depends on how strong it gets. It could be a rain maker, at least.

This storm may take off to the north and northeast over time, but I doubt it will be anything tropical by that point because of the unfavorable environment ahead of it. It's still worth watching. Stay tuned to my Twitter feed for the latest. I might post another blog entry in a day or two, if conditions (and time) warrant.

Saturday, October 22, 2011

Quick Overview: Plantation/Sunrise, Fla. Tornado

On Tuesday night (Oct. 18), an interesting weather pattern was setting up in south Florida. At the same time, I was watching the town hall session at the National Weather Association annual meeting in Birmingham, Alabama.

When me, Dan Goff, and 100+ meteorologists were listening on to what some of the general public thought about the warnings and the societal reactions to the April 27 tornado outbreak, I was checking my Twitter feed and discovered something interesting. The National Weather Service in Miami issued a tornado warning for parts of Monroe and western Miami-Dade counties. The storm was racing off to the northeast over the Everglades. It was far from the major metro areas along the east coast - I considered it an "alligator" storm.

The storms across south Florida had the potential to rotate and possibly spawn a few tornadoes. The Storm Prediction Center had issued tornado watches for the area and has issued several mesoscale discussions (such as this one and this one). 

At 8:30 p.m. ET, the rotation seems to intensify on the velocity scan (see below). Dan and I were pretty amazed on how good it looked on radar. It looked like it was still an alligator storm, if not a tornado on the ground. I started to become concerned about this storm if it continued at its current strength toward northern Miami-Dade or southern Broward counties.

Screenshot of KAMX velocity tilt 1 scan using RadarScope on iOS 5.

Over time, the storm moved in a northerly direction and began to lose its impressive velocity signature.

However, NWS-Miami issues another tornado warning for parts of Broward.

Reports of damage start to flow in from the Plantation and Sunrise area of damage from a possible tornado at roughly 10:07 p.m. ET, according to NWS-Miami's storm assessment (PDF). About 4 minutes before the tornado was thought to have initiated, a scan from the Miami radar shows some possible rotation with the velocity scan (top right), while the storm relative (bottom left) shows slight rotation. The spectrum width (SW) (bottom right), which is used to essentially measure turbulence and associated with thunderstorms and mesovoritcies. 

The storm continues to move off to the northeast for 1.11 miles doing a max of EF-2 damage with maximum winds of 120 mph. It aslo continues to lose its appearance on the Miami radar.


The NWS in Miami gave ample warning for this storm as it had a history of showing rotation on radar, especially over the Everglades. Based on the stories told by the local media, it's great news that there were few injuries and no deaths associated with this tornado in a highly populated area.

With all the talk that Tuesday night in Birmingham of how people reacted from the April 27 outbreak, I wonder if anyone in the area received these warnings and how they prepared for it, especially since it was a tornado that arrived after dark. 

Saturday, August 27, 2011

Irene Makes Landfall

Hurricane Irene made landfall this morning near Cape Lookout, N.C. at 7:30 AM EDT with winds of 85 mph, a category one hurricane, according to the 8 AM advisory from the NHC. The landfall occurred 10-15 miles to the east of were I thought it would be, but it is a little weaker than I expected. I believe the dry air intrusion Friday afternoon and night was mostly to blame for the decrease in intensity. The current intensity, as of 11 AM EDT, is still at 85 mph with a central pressure of 952 mb. The pressure is still hanging around the 950s.

Irene is still expect to make a north-northeast trek and start accelerating in forward speed. It could maintain weak hurricane status until it reenters the Atlantic and move along the New England coastline. The threat remains of some storm surge, especially during high tide, but it shouldn't be as bad as expected. Wind is still a threat, especially in cities with large buildings in close proximity ("wind tunnel" effect could make the winds higher than normal). Inland flooding is also a high risk, especially along rivers and low-lying areas.

For the latest, keep any eye on my Twitter feed.

Friday, August 26, 2011

Irene Update

Well, Floridians can breathe a sigh of relief as Hurricane Irene has and will move north and away from the state's east coast. Irene still had effects on Florida though as rain bands from the western edge of the storm impacted the east coast areas of central and southern Florida. Wind gusts as high as 30 mph were reported in south Florida Thursday afternoon. It's likely that Florida's east coast will continue to encounter heavy surf and a high rip current threat.

Currently, Irene is east-northeast of Jacksonville, Fla. with winds of 100 mph and moving north (360 degrees) at 12 knots. The odd thing is that the central pressure is 951 mb. The winds seem fairly light with relation to the low central pressure. This could be because of a weak high to the east of Irene, which would lead to a lower pressure gradient and, therefore, lighter winds. [Mets: If I am wrong, please chime in on this]. The intensity has decreased a bit from earlier today, likely due to dry air intrusion into the system from the southeast based on water vapor satellite imagery.

I am not expecting too much change in strength through landfall, which is expected sometime tomorrow morning. Models are in agreement of an mid to upper trough to move through the Great Lakes and move east. This, along with Irene being on the western edge of the ridge, should keep Irene moving north - maybe a little more north-northeast - and make landfall along the Outer Banks of North Carolina. Based on the certainty of the models and time to landfall, I am confident that a landfall near Morehead City, NC is likely. I think Irene could still be a category two or strong category one hurricane at landfall Saturday morning. There could be some slight weakening as dry air entrainment could pose a threat to the TC. Shear doesn't seem to be an issue anytime soon as outflow looks really nice.

The concern is that the storm is relatively large and can have impacts far from Irene's center of circulation. Storm surge is still a concern on the coast along with heavy rain to areas that have received plenty recently. Because of the large population centers in New England, the societal impacts of Irene will be great.

Since my thesis research falls along the lines of TC and tornado relationships, I should elaborate on a possible tornado threat. Tornadoes from TCs tend to develop on the right-front quadrant of the storm. Literature also points out a higher incidence of TC-tornado outbreaks when dry air entrainment and, therefore, steep relative humidity gradients occur (Curtis 2004). This is something I will try to keep my eye on as the hours move on. For now, the SPC has given a Mesoscale Discussion for the Outer Banks. There is not a high enough risk to issue a severe weather watch at the moment, but the conditions for tornado development could increase later tonight, according to their discussion. Still, with this dry air entering the storm and seeing some decent banding taking place north of the center on visible satellite (see above) has me kind of vigilant.

I will have more on Irene later.

Monday, August 22, 2011

Hurricane Irene Update

A lot has changed in the last couple of days. Tropical Storm Irene came to life Saturday evening as hurricane hunters found a weak circulation and central pressure of 1006 mb. Two days later, it's now a storm that has passed over Puerto Rico and has become the first hurricane of the season. The 8 PM EDT advisory now has Hurricane Irene at category two status with winds of 100 mph and a central pressure of 981 mb.

The last few visible satellite frames show a nice-looking storm. Latest infrared satellite imagery shows Irene continuing to intensify with high cloudtops, mostly around and north of the current center fix (19.7 N 68.7 W).

The storm is not moving over the islands (Hispaniola and Cuba) and is not expected to. This leaves the door open to intensification as it moves west-northwest, then northwest as it is expected to encounter a weakness in the ridge over the Atlantic. The guidance models have shifted more east in the last two days, which is a change from where previous runs had Irene hitting Florida Friday into Saturday. Major guidance models - with the GFDL as an exception - have the storm remaining over the waters close to Florida and eyeing the Carolinas for a landfall. The GFDL has been persistant on a Florida landfall and is considered a outlier at the moment.

Southwest Florida Water Management District
As this storm remains over the open waters, my fear is rapid intensification. This is especially the case as Irene reaches the Bahamas. With water temperatures in the low 80s (pushing 85 in some spots), good outflow, no immediate threat of dry air intrusion, and very little shear, I don't see any reason for it not be a category three or four hurricane. This storm has the capability of being a monster TC and needs to be watched.

I've had a lot of friends from Florida ask me about this storm in the last couple of days and, of course, have not been able to give solid answers. With the storm at least five days from Florida and another day or two from the Carolinas, I don't trust the models this far in advance. I think the chances of a Florida impact are lower now, but I wouldn't completely rule it out. People in the NHC cone of error - from south Florida to North Carolina - need to keep an eye on Irene.

I'll post more on this storm in the coming days. Keep tabs on my Twitter account (twitter.com/daweathaman) for the latest.

Friday, August 19, 2011

Watching Invest 97L

It's been a while, but it's a good time for a blog post since the fall semester is now here and the hurricane season is starting to ramp up.

I'll start with something that has been catching eyes in the meteorological community. For the last few days, guidance models have been developing a tropical cyclone (TC) to arrive fairly close to the southeastern U.S. coastline nearly a week from now. On Thursday, the NHC has designated this area of concern as Invest 97L.

The vis-sat shows 97L as a decent wave with little shear in the environment. Shear analysis indicates values around 10 kts. Movement has been westerly at nearly 20 mph. Infrared satellite loops show more organization and colder cloudtops in the last few hours. There was some concern of what the Saharan Air Layer (SAL) surrounding 97L would do to it, but it seems that the SAL is not as intense as it was Thursday. It looks as if the wave is doing a good job avoiding dry air intrusions at the moment based on water vapor imagery.

So, what will happen? It's expected to approach the Lesser Antilies on Saturday where conditions could still be favorable for development. Shear is expected to be relatively low. The NHC is giving it a 40 percent chance of development for the next 48 hours. I'm confident that the chances will increase, at least through Saturday. Guidance models are in fair agreement of 97L moving toward the west-northwest and getting close to Puerto Rico and Hispaniola at the beginning of next week. What happens beyond that is iffy...

The system would eventually take a more northerly path. The GFS, at this moment, has the storm hitting the western side of Florida and striking the Big Bend next weekend. The Euro has the storm hitting the southeastern coast of Florida and moving north-northeast to northeast a day later than the GFS. It would depend on a) how strong the ridge to the east is and b) any troughs in the eastern U.S. to help "pick up" the storm. For example, the GFS seems to have the Bermuda High fairly strong and keep it more west than the Euro. Other models don't go this far out.

If 97L / future TC moves over the islands (Hispaniola, Cuba), they can have an effect on further development of the system and even decrease its strength. The mountainous terrain can do some damage to a healthy TC. If the wave / TC doesn't cross the islands as much, it may not lose so much strength. It all goes back to the path of the storm, which is still highly uncertain.

When I start to see consistant patterns in a guidance model (run-to-run) and the guidance models agreeing with each other, my eyes start to get wider. Still, I have a hard time trusting guidance models beyond three or four days. I'm not comfortable making calls this early in the game. My advice: People from the Carolinas to Brownsville, TX need to watch the tropics for the next week. Things might get interesting.

Saturday, May 28, 2011

Footage to air on National Geographic Channel

Some of my footage from the April 15 tornado outbreak will air on the show "Witness: Tornado Swarm 2011" on the National Geographic Channel this Sunday, May 29 at 9 pm ET (8 pm CT). There should be at least 54 seconds of footage from my chase with Cecilia Reeves and Evan Thomas, two other meteorology graduate students from Mississippi State. Storm chasers Jim Edds and Jeff Gammons will also have footage aired from their storm chasing last month. Meteorology faculty from Mississippi State, Greg Nordstrom and Michael Carter, will also have footage aired on the episode. For more info on the show, check out the web page from Nat Geo.

Jim Edds and Jeff Gammons will also have their hurricane footage aired on NatGeo's "Explorer: Stormageddon" one hour before "Witness" (8 pm ET/7 pm CT).

Be sure to check out the National Geographic Channel Sunday night.

Saturday, April 30, 2011

Chase Log: Wednesday, April 27, 2011 - Eastern Mississippi / Western Alabama

When Wednesday, April 27, 2011 began, I knew it could be a crazy day. But never in a million years did I think it would be as phenomenal or deadly of historic proportions as it was.

As I mentioned in the last two blog posts, this event carried a high risk of tornadoes - even strong ones - with severe wind and hail probable. With this in mind, many meteorology students at Mississippi State thought of firing up their cars and smart phones and heading out to observe and document this force of nature. My girlfriend and broadcast meteorology undergraduate student Damaris Jaime and I planned on doing some storm chasing as well. Also, friend and storm chaser Jim Edds was in Starkville to position himself for chasing these storms. Damaris and I randomly ran into Jim at a McDonalds in eastern Starkville. Jim was watching the radar and chatting on the phone with friend and storm chaser Jeff Gammons, who was at his home in south Florida monitoring the weather for Jim. Jim offered us to follow him in his chase and we left Starkville. Since Jim and I are both licensed ham radio operators, we mostly communicated on the 2-meter band with our handheld radios.

Jim waiting for things to fire up.

We initially set out for west of Starkville, but Jeff then suggested we moved south for a supercell near Philadelphia, Miss. After being separated for a bit, we caught up with each other south of Macon, Miss. and attempted to position ourselves for this storm that was on its way to the area. After some position changing (see video below), we managed to find the rotating storm and got video and photos of it.

Storm to the south of Macon, Miss.

Damaris shoots video of the storm to the south of Macon, Miss.

We got word of a cell to the southwest of us that was on the way to Scooba, Miss. Sound familiar? We moved south and positioned ourselves at a gas station and faced our cars west to wait for the storm. We got a little rain, pea-sized hail and some really close lightning strikes before we saw rotation and a wall cloud.


Damaris noticed the rotation first. Jim then moved his car to the overhang at the gas station while we stayed put. Damaris shot some of the video as it moved from our 12 to 3 o'clock. Then I grabbed the camera and got what appeared to be a developing tornado roughly 600 feet to my north. Below is the video of the developing tornado.

After seeing that, we then proceeded westbound on State Road 16 to try to catch up with the storm. In the process of doing so, we witnessed three storm chase vehicles - one being a tour van. When we had clearing, we saw what looked like a tornado on the ground probably a couple of miles to our north. We only had a couple of seconds of video of it until we lost it in the trees and the rain. Jim said there was a north-south road we could take to catch up with it. We finally stopped in Geiger, Ala. - a town that was already hit by a tornado on April 15. A lot of the damage from that tornado remained. It was sad to think that this town could get hit again by another one. Luckily, it turned out not to be the case as nothing developed from that supercell that continued to move towards the northeast.

As we were leaving Geiger, we witnessed The Dominator, a vehicle designed for storm chasing in part by Reed Timmer, with the Discovery Channel support crew behind them. Of course, I incorrectly called it the TIV on the video. Sorry, Reed.

We then stopped on a long bridge (State Road 39) over a river near Gainesville, Ala. We could see the tornado far in the distance that was quickly becoming wrapped in rain. I was losing contrast, so I grabbed whatever photos I could while Damaris grabbed video. Below is the tornado with the last bit of video.


We then proceeded to follow Jim so we could get to I-20 and chase this supercell as it moved towards Tuscaloosa. Along the way, Jim went really far ahead of us and we lost communication via the ham radio. We ended up taking a wrong turn, getting lost temporarily, and winding up near I-20. By time we were able to look at the radar - thanks, AT&T for your crappy cellular service - the cell was 30 miles away. Because of the slow Internet speed, I was only able to pull up storm relative velocity on RadarScope. The radar scan showed rotation that really stood out. It looked like a bad storm. Still, we knew there was no way we could catch up with it and decided to call it a day. After running into a road block (tree on the middle of State Road 14), we went back on I-20 southbound to State Road 28, then took State Road 17 northbound (which paralleled the AL/MS state line) to try to get back home. Along the way, we saw a cool sunset which was a nice way to end a crazy chase day.


At this point, we did not know about the chaos that occurred in Tuscaloosa and Birmingham. We started getting phone calls regarding a massive power outage in the Golden Triangle area that most said could last days. We later found out a substation was taken out by a tornado to the north of Starkville that helped supply power to at least three counties.

Expecting basic services to be out in Starkville, Damaris and I stopped for food and gas in Macon. That's when I was able to check my Twitter feed and find out about the massive devastation that took place in Tuscaloosa and Birmingham. I was blown away from the photos I saw on Twitter. It looked really bad. Jim called me and said he missed the tornado, but witnessed a lot of damage. He grabbed some aftermath footage and interviewed a UPS driver who was caught in the mess (video of damage and interview with UPS driver).

It was eerie driving through Starkville with no street lights or power at homes and businesses. The Piggly Wiggly grocery store was the only place on the way back to Damaris' apartment that had backup power, and the store was packed with people.

I kept checking my Twitter feed on the phone during the night and continued to get a glimpse of what really happened. It was depressing to see all of the destruction and the ever increasing death count.

Three days later, I am amazed at the storms Damaris and I witnessed but saddened at the devastation that took place in parts of Mississippi and Alabama. This severe weather event exceeded what I expected. So far, at least 350 are dead across the south - 249 dead just in Alabama - according to Reuters. Damage from this outbreak could be between $2 billion and $5 billion. This could be the second deadliest outbreak in US history, topping the 1974 Super Outbreak.

For my second storm chase ever in Dixie Alley, I was able to see tornadoes and the damage they could cause to life and property. As a meteorology student, I find these storm fascinating but deadly. Events like this keep me motivated to continue studying this field and one day be able to effectively issue life saving warnings to the public.

My thoughts and prayers are with those affected by this outbreak.

Below is an image of the cell we chased from Scooba, Miss. to north of Gainesville, Ala. It turns out this supercell kept firing up tornadoes all the way to North Carolina. Insane. Thanks, David Cox for sharing this with me.

Brian Tang/David Cox, Facebook

Wednesday, April 27, 2011

High Risk of Severe Weather Today for the Starkville Area

Good morning, everyone. The early morning hours were pretty wild with a line of storms passing through and near the Golden Triangle area that causing some damage with a possible tornado to our north near Euproa. Unfortunately, this severe weather threat is not over. The Storm Prediction Center has placed parts of northeastern Mississippi - including Starkville - under a high risk of severe weather today. This is something that isn't issued very often and should be taken very seriously.

A surface low is sitting over Arkansas with a cold front over eastern Texas. At 850 mb, winds are primarily out of the southwest between 50 and 60 knots - a very strong low-level jet. A 500-mb trough sits over Oklahoma and Texas with the SPC Mesoanalysis showing really good divergence aloft downstream (see below).

At 300 mb, a jet streak can be found near the rear, NVA side of the jet stream.

Visible satellite imagery shows storms firing up near the the delta in Mississippi and Arkansas with storms to our north. Columbus Air Force Base radar shows strong to severe storms near Tupelo north to neat Iuka.

The models show the mid-level trough kicking through the area and becoming negatively tilted by roughly 0Z. The 850 mb winds will likely die down by 0Z, as well. The SPC has noted that temperatures have quickly rebounded this morning; therefore, further destabilization is expected to continue. The jet streak aloft, the approaching surface low, good diurnal heating, good moisture flow, and good dynamics spells trouble for the area.

The SPC has issued a mesoscale discussion which states a PDS tornado watch may be issued soon...


There is a good chance that I will be chasing this afternoon across the state. As for everyone else, be on the lookout for rapidly deteriorating conditions. Keep an eye on my Twitter feed for the latest.

Tuesday, April 26, 2011

High Risk of Severe Weather for Parts of TX/AK/TN/MS

It was a wild weather day on Monday as tornadoes smashed across Arkansas, including Vilonia where the death count now stands at 4 (story from CNN). The same system may bring more storms to roughly the same area as Monday evening.

Currently at the surface, a 994-mb low sits over southern Wisconsin and northeastern Iowa with cold front stretching through Missouri, Arkansas and Texas. Dewpoints in the 60s can be found along the lower Mississippi River delta with a good southerly surface winds of roughly 15 knots at best. At 850 mb, the winds veer a bit to more out of the southwest at 40 to 50 knots. SPC mesoanalysis at 700 mb show winds remaining mostly southwest but become more west in northern Mississippi. The 700 mb layer also gives a hint of little shortwaves embedded in the trough near the Texas and Oklahoma panhandles. The 500-mb mesoanalysis show a trough with over the central plains with what looks like embedded shortwaves - one over Illinois and the other near Colorado. The 300-mb map appears somewhat similar to the 500 mb map with respect to patterns.

Both the GFS and NAM indicate a strengthening 850 mb southerly jet bewtween 0Z and 9Z Wednesday over the southern states with the GFS firing up the jet at 0Z. This could aid in pumping more moisture and warm air during the overnight hours. The 500-mb NAM gives a hint of divergence over the delta, but notably over Arkansas while the GFS indicates the same thing. Since the NAM is a mesoscale model, it indicates more vort maxes due to the embedded shortwaves in the trough. The NAM is showing some pretty good helicity numbers late tonight and early morning over the delta region. The RUC is indicating a dryline boundary over eastern Texas. Storms could initiate from this line in the evening hours.

Based on the model runs, it appears as if the best chance of severe weather will be overnight starting in Texas near this dryline and would move further east and enter more of a favorable environment. In the SPC's discussion, some things aren't clear...


How they know/don't know the evolution of the storms is out of my league of knowledge at this point. If any mets out there can explain that to me, I'm all ears.

The SPC has moved the high risk to include extreme northwestern Mississippi. Starkville is only under a slight risk category through 12Z Wednesday. The SPC highlights our area with a moderate risk for day two (12Z Wednesday to 12Z Thursday).

For now, a high risk for a tornado outbreak looks probable for parts of Arkansas, Mississippi, Tennessee, and Texas. People living in those areas need to take this event very seriously. Make sure you have a NOAA Weather Radio on standby tonight and keep tabs on the weather before you go to bed. Starkville looks to be in the red on Wednesday. I'll have a better handle on things as Wednesday approaches. Stay tuned to this blog and my Twitter feed for the latest.

Wednesday, April 20, 2011

Another Day of Severe Weather

Five days after Cecilia, Evan, and I got to see our first tornado, another round of severe weather has made its way to the Starkville area. Insert a stationary front with some instability and decent dynamics, you get the slight risk of some severe weather. I wasn't sure if things would remain favorable later today for severe weather, but my novice knowledge of mesoscale meteorology once again proved me wrong.

This afternoon, I was watching a cell to the northwest of Oktibbeha County that was moving towards the area. It maintained a hook echo with some pretty high reflectivity values and VILs pushing into the 60+ mark according to the Jackson NWS radar (since the Columbus AFB radar seems to be out for "maintenance." Good timing, NWS...good timing). I decided to head home from campus and noticed a pretty nice cloud formation on the west side of town. I quickly went to my apartment, grabbed my camer, put on some chase-appropriate shoes, and drove a mile or two away to get some photos. Here are a few...




I then decided to cross the street to get a better view of the storm as it continued to move to the east-southeast.


The storm then dumped really heavy rain with some pea-sized hail. Some gusty winds at one point even prompted me to take shelter at a nearby Waffle House for a few minutes.

On the way back to my apartment, I noticed some flooding along Stark Road.



There are still plenty of storms firing up to the west of Starkville with the potential for severe weather. Things should begin to quiet down later this evening as daytime heating is lost. Keep an eye on my Twitter feed for the latest.

Saturday, April 16, 2011

Chase Log: Scooba, Mississippi


It has been a while since my last post. Life, as usual, has been getting pretty busy. Life was pretty interesting Friday as there was a severe weather threat for some southern states. Mississippi was included under a moderate risk of severe weather. After a short discussion of the weather situation in Weather Analysis II - and learning that the best helicity would be to our south in central Mississippi - graduate meteorology students Evan Thomas, Cecilia Reeves, and I contemplated a chase. We decided to catch the cell that impacted the Jackson, Miss. area and produced a tornado. We originally thought of heading to Macon, Miss via U.S. Hwy 45, but later realized that being further south near Scooba, Miss. would be our best bet. We kept an eye on the radar on our smart phones and adjusted our position periodically. When we slowly started edging our way back to the north, we saw a lowering to our northwest above the tress. Sure enough, it was a confirmed tornado just south of Scooba. For all of us, it was our first tornado experience. I still can't get over that find. I sobered up a little after seeing some of the damage on the way back to Starkville, including an SUV that appeared to have flipped multiple times.

Below are a few photos and a video of our chase adventure.





Saturday, March 5, 2011

Severe Weather Threat to Move Towards The FL Panhandle

The severe weather mess that has has affected Louisiana this morning and early afternoon will continue to move towards the east this afternoon and tonight. The NWS-Slidel, LA radar continues to show a potent line of thunderstorms with embedded bow echoes moving into southern Mississippi. The NWS-Mobile radar is beginning to pick up the storms real well, also.

Source: UCAR

Surface analysis (above) from 20Z indicates southeasterly flow over much of the Florida panhandle, southern Alabama and Mississippi. The winds veer with height to nearly out of the west at 300 mb according to the SPC mesoanalysis. The CAPE doesn't seem to be as strong as it was earlier over southern Louisiana. However, the storm relative helicity values are pushing 400 ahead of the line of thunderstorms based on the SPC mesoanalysis. The SPC is maintaining a slight risk of severe weather for extreme southern Mississippi and Alabama, and the Florida panhandle.

Source: WeatherTAP.com

The shortwave trough and surface front is expected to continue to move towards the east and maintain the line of activity. The instability and shear look to continue this afternoon and provide a risk of mostly damaging winds, but I would not rule out a tornado or two. The SPC is counting on the severe threat to diminish by 6Z (midnight CST) according to their latest discussion.

I'll try to keep an eye on this during the afternoon and evening. Keep tabs on my Twitter feed.

Tuesday, March 1, 2011

Photos from NWS-MOB Tour

Here are a few photos I got (except for the last one) during our tour of the NWS office in Mobile, AL on Saturday after SeCAPS. I would like to openly thank WCM Jeff Garmon for offering and giving us a tour of the office.

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Photo by Joel Young
Thanks, Joel for letting me use this photo. I just look kinda angry in my other photos (I was not angry, though).

Monday, February 28, 2011

Severe Weather Update: Nothing But a Fizzle?

Things don't look very interesting for severe weather in Mississippi this morning. Current surface analysis shows temps over the state in the low 70s with dewpoints in the 60s (see below).

Source: College of DuPage

It was actually 71 at my apartment this morning...at 6:50...in February. The sun has been out this morning, which is good for heating the surface and helping to destabilize the atmosphere. However, there is one problem and it's indicated on the 12Z sounding from Jackson, MS: The cap.

Source: Storm Prediction Center

There's a decent cap along with very dry air aloft. I wish, wish, wish there are balloon launches in Memphis. Regardless, if there was a sounding launch in Starkville the readings would likely be the same as JAN. The MLCAPE isn't too bad, but the veering winds with height aren't too impressive. The radar is not impressing me, either as there is only a line of what appears to be a "wanna-be squall line." The setup isn't at it's prime right now. At this moment, I'd have to say chances are good that the severe weather threat for the Starkville area appears to be a bust. The best chances of severe weather will be to our northeast today where the SPC has northern Alabama, parts of eastern Kentucky, and northern Georgia under a moderate risk.

Sunday, February 27, 2011

SeCAPS; Slight Risk of Severe Weather for Mississippi

I am back in Starkville from attending the Southeastern Costal and Atmospheric Processes Symposium over the early weekend in Mobile, Alabama. I had a great time seeing speakers and interacting with meteorologist. I even had the chance to meet Dr. Chuck Doswell - a very cool guy and renowned atmospheric scientist. If you are a meteorologist or met student and don't know who Dr. Doswell is...something is wrong with you. We (other MS State met students and I) also had a the chance to tour NWS-Mobile, which is the fifth NWS office I have ever set foot in. Stay tuned for pics from the post-SeCAPS tour. I had a great time.

Now on to what's happening in the weather...

The Storm Prediction Center has placed parts of northwestern Mississippi under a slight risk of severe weather through 12Z Monday (6 am CST) and most of Mississippi under a slight risk after 12Z Monday. Points northwest and then northeast of Mississippi will be under a moderate risk.

Current analysis indicates a surface high off Florida's east coast. A southerly flow is taking place over the gulf states with dewpoints mostly in the 60s. A surface low is also located over the Texas and Oklahoma panhandles (see below). There are very strong winds over Texas with some reports of gusts over 60 mph. Upper air observations at 700, 500 and 300 mb show a trough over the southwestern United States.

Source: College of DuPage

The trough is expected to push towards the east and then northeast along with the low. Through the night and Monday morning, a deep south to south-southwesterly flow at 850 mb and veering with height to be at almost out of the west over northern Mississippi. The shear could be somewhat decent and instability could be a a tad better with the possibility of CAPE being at least 500 J/kg based on the NAM.

I'll have to wait until the morning to see how things pan out. For now, keep an eye on the skies in Starkville Monday morning. Stay tuned.

Thursday, February 24, 2011

Quick Update: Severe Weather Threat in Northern MS Today

Good morning, everybody. My schedule is pretty tight today, but I'm going to try to quickly explain what could go down today. The Storm Prediction Center has highlighted parts of Arkansas, northern Mississippi, and Tennessee under a moderate threat of severe weather. This categorical threat isn't issued too often.

Currently at the surface, a strengthening low is centered over northern Texas. Winds are primarily out of the south over Mississippi with dewpoints climbing into the 60s in the southern and western parts of the state. The dewpoint at KGTR is 55 degrees. Aloft, a shortwave trough is located over New Mexico. At 850 mb, a decent south-to-north low-level jet of up to 45 knots is over eastern Texas. This could be a key player in enhancing moisture and warm air advection.

The trough to our west is expected to progress east throughout the day and, along with it, the surface low over Texas and Oklahoma. This will provide uplift for the development for showers and thunderstorms. However, there are other key elements that make this severe threat possible. The shifting of the winds with height could produce enough shear to give way for a tornado risk and some strong winds. The next key ingredient is instability. Will there be enough moisture and warm air over the Golden Triangle area to give way to severe weather? If there are any breaks in the cloudcover to heat things up, I'd say "look out." I am not seeing any signs of that on the visible satellite imagery so far this morning.

Regardless, people need to be tuned into the weather throughout the day. The timing of a possible Starkville impact of this weather seems to be later this evening and tonight. Keep an eye on my Twitter feed (twitter.com/daweathaman) for the latest.

Saturday, February 19, 2011

NOAA Budget Update: House Passes Massive Cuts

I'm back on my news and soap box this morning as I just received news that the U.S. House of Representatives bill to slash domestic program's budgets passed 253-189, according to the New York Times. The vote was pretty much along party lines as Republicans fresh from their November victories wanted to show their strength of fiscal conservativeness. In my opinion, it showed their strength of witlessness.

As I mentioned in a recent blog post, this bill also contained drastic cuts to the NOAA, in which the National Weather Service falls under. The bill requested that NOAA's budget be cut nearly 30 percent according to the National Weather Service Employees Organization. The effects of this bill, if enacted, could include closing some weather forecasting offices (WFOs), layoffs, disrupt or even eliminate Hurricane Hunter aircraft missions that supply important data, and reduced accuracy and amount of weather data that's crucial for accurate weather forecasting.

The bill has passed the House, but it still has to go through the Senate and be signed by President Obama. The good news is that the cuts might have a harder time passing through the Senate because of the 51 seats held by Democrats, but the Republicans have filibuster power. In other words, it's not over. There's still a fighting chance. That's why I encourage you to write your local congressional delegates and senators and tell them to stop the madness.

By the way, here are roll-call votes from the House bill (via the NYT): http://politics.nytimes.com/congress/votes/112/house/1/147.

Thursday, February 17, 2011

Slight Chances of Rain Starting Early Next Week

It's been chamber of commerce weather for most of the southeastern U.S. for nearly the last week. Temperatures have been running near or even above normal in some instances. Most of the upper-level features that have been feeding us gifts from Old Man Winter have remained to the north or back in the western U.S.

Things will change at the beginning of next week, but not too much. The GFS shows a large trough over the western U.S. during the early weekend and moves it to the west. The trough begins to demagnify Monday morning and become a shortwave. The GFS shows the wave remaining just to the north of Mississippi Monday night and Tuesday morning. The model indicates a surface low and cold front with most of the precip to the north and east of the low. The European model shows a surface low to the north, but Monday morning.

I don't get the impression of this system brining in much rain. Things should clear out by the end of Tuesday. There should be some nice weather for the short term. The GFS hints at another system moving in around next weekend. The NWS in Jackson also points out this system in their latest AFD. However, it's a week out and it's a guidance model; therefore, I don't feel confident in saying much about this system.

For now, most of the weekend looks very nice. Enjoy it!

Wednesday, February 16, 2011

The Proposed House Budget for NOAA: Disaster

Today's blog post has a little more of a different tone, but it's on a topic that deeply concerns me and should concern all of us. I usually don't like to get very political on social media because of how sensitive people can be these days, but the latest news I've read is making me speak out.

In today's atmosphere (no pun intended), the need to cut budgets due to less revenue has been a hot topic. Not just a local and state level, but also the national level. The last few years, the federal budget has been dipping heavily into the red. In my mind, both political parties are to blame. Regardless, both parties are sensing the frustration of us taxpayers and desire to get spending under control. However, each group has it's own way of doing it - one is to make smaller cuts, the other make drastic cuts.

The Republican-controlled U.S. House of Representatives seems to be taking more of the drastic approach. In their proposed budget, the House would like to cut programs and scale back others to save at least $35 billion according to the Associated Press.

According to material presented by Rep. Harold Rogers, R-Ky., chairman of the House Appropriations Committee, the cuts would stretch across a vast range of domestic programs, from the EPA to housing, the weather service, food safety and inspection and the U.S. Army Corps of Engineers. The Community Development Block Grant, which provides funding for municipalities, would also be cut.

Yep - they said the National Weather Service. The agency that provides forecasts, life-saving watches and warnings, and provide weather data that is fed into forecast models could suffer massive cuts. The National Weather Service Employees Organization released a press release that spells out disaster for the agency if these cuts go through...

Congress's move will necessitate work furloughs and force rolling closures of Weather Warning Offices across the country. The effects will be felt in every aspect of daily life, including emergency management, television weather, and information used by our nation's citizens for transportation, commerce and agriculture.

The National Hurricane Center, the Storm Prediction Center, the Aviation Weather Center, the Tsunami Warning Centers, River Forecast Centers and local Weather Forecast Offices located in communities across the nation are all victims of Congress's budget cut.


Reduced funding will mean upper air observations currently made twice a day might be reduced to every other day. Buoy and surface weather observations, the backbone of most of the weather and warning systems, may be temporarily or permanently discontinued. Delays in replacement satellites run the risk of losing key weather data that can be obtained no other way. "This information is vital for weather modeling and essential for accurate tornado watches and warnings," said Sobien.

The National Hurricane Center is not immune to these cuts as furloughs and staffing cuts will add strain to the program. The Hurricane Hunter Jet, which provides lifesaving data and helps determine a hurricane's path, could also be eliminated.

This view is pretty scary. It would also impact many of my friends, including me, who desire to work for NOAA once they get their meteorology degree.

I understand that budgets need to be cut in order get the country out of the red, but common sense needs to be applied when deciding what to slash. Then again, common sense has not been applied much in congress in the last few years. Extreme partisan politics has taken priority over the needs of the country.

If the House's proposed budget cuts go through, many lives would be in danger from lack of adequate equipment maintenance, staffing, and lack of constant and accurate weather data. This would lead to lack of accurate forecasts and timely warnings. Simply put: People could die.

There are many other essential programs that the House GOP would like to cut or eliminate which include the Corporation for Public Broadcasting, education (then again, that's typical), the EPA, and food inspection. Even cuts to the Army Corps of Engineers are on the table. Despite the devastation from Hurricane Katrina, some politicians think that cutting funding to the Corps is still a great idea.

I highly encourage you to write to your senators and representatives and tell them to use common sense in cutting budgets. They need to think about what they are doing and find other sensible ways to save money.

Saturday, February 12, 2011

From Snow to Warmth

Good afternoon, everybody. After dealing with cold - and even some snow here in Starkville - the warm up is on its way. By the way, you can check out some of my snow photos on my photo blog.


Currently, a 1035-mb high is centered near the Texas coast according to HPC surface analysis. This high will help bring very nice weather to the south today and tomorrow. Both the NAM and the GFS show a upper trough over the Great Lakes region on Monday morning. A frontal system is expected to be associated with the trough, but a lot of the energy will be way to the north and not affect the southeast very much. In fact, NWS-JAN still has clear skies in the forecast Monday and Tuesday. Highs on Wednesday could even push towards the 70-degree mark.

Wait - what?

Warm weather?


But why? After the crazy winter weather pattern we've had this winter, why the change? Well, things are starting to become more zonal in the upper-air patterns, at least for the eastern United States. Teleconnections can also play a part in the shift. For instance, the Arctic Oscillation (what is the AO?) is generally going towards more of a positive phase (see graph below).

Climate Prediction Center/NOAA

This can mean stronger westerlies in the Arctic region to be stronger and keep colder air to the north. The North Atlantic Oscillation is expected be close to normal. A negative NAO phase would help bring colder air to the eastern United States. Therefore, the more neutral phase should keep conditions near average.

In a nutshell, the weather looks to be nice and warmer in the southeast, including Starkville, for at least the next five days. Enjoy it!

Tuesday, February 1, 2011

Severe Weather Update

The latest weather data is indicating not so fresh of a severe weather threat for Starkville. The dynamics don't seem to be building as much as it could have.

Currently, the line of thunderstorms is over southern Louisiana and extreme southwestern Mississippi. The line looked very potent a few hours ago, but it's not so impressive now. There are a few embedded cells that are spawning severe thunderstorm warnings, but again, not as impressive as it was earlier.

Dewpoints (colored) across the SE. (Via NOAA. Thanks to @Cuevman81 for sending this).

The 60F dewpoints that I mentioned on the earlier are still south of the Starkville area. I'm not seeing much of a indication of northward advancement. With the lack of good moisture and WAA, and no breaks in the clouds to destabilize things will keep the risk of severe weather north of I-20 minimal. I won't rule out a squall line with a somewhat decent punch, but it's looking less likely for severe weather here. The best chance of severe weather looks to be south of I-20 where most of the 60F+ dewpoints will be. However, there are no breaks showing up on the visible satellite imagery to give way to further destabilization.

More updates when needed...

Severe Weather Threat Today in the South

Today looks to be rather a record-breaking, if not crazy, day in the weather world. At least a half-dozen states look to see a massive blizzard that will paralyze areas of the Midwest. This storm will also bring a risk of severe weather to the southern states, including Mississippi.

The Storm Prediction Center is calling for the severe weather threat today over far-eastern Texas, Louisiana, Mississippi, most of Alabama, and western Florida.

The upper-level trough over the plains and a powerful cold front and surface low continues to move east. As this system progresses, the southerly low-level flow should continue to enhance some warm air advection. The models show the best moisture later this afternoon over central and southern Mississippi with dewpoints at or above 60F. However, the Helicity values are in excess of 500 m^2/s^2 over the Starkville area this afternoon. Still, for the Golden Triangle to receive the best chance of severe weather there needs to be more moisture and warm air advection. Any breaks in cloudcover today could also further destabilize the atmosphere.

The primary threats from this storm seem to be hail, strong winds and an isolated tornado. There is already a tornado watch in effect for parts of LA and MS until 3 PM CST. Stay tuned to TV, radio, Internet, and/or NOAA Weather Radio throughout the day. Also keep an eye on my Twitter feed (twitter.com/daweathaman) for the latest info.

Monday, January 24, 2011

Severe Weather Risk in Florida Tuesday

After a week of tranquil weather in the Sunshine State, it appears a chance of strong to severe storms is in the works Tuesday. Currently, a developing surface low pressure system is hugging the Texas coast as it moves east. This system is helping to dump rain in parts of the south, including west-central and southwestern Mississippi. This rain will continue to move west tonight and impact Mississippi State tonight and tomorrow (more on that in another blog post).

The guidance models are in agreement that a positively-tilted, upper-level trough will amplify throughout the night. This trough is expected to push towards the east Tuesday. Models are also showing 850-mb winds blowing decently out of the southwest - as high as 35 knots - and will aid in warm air and moisture advection to Florida. There is also a chance of having enough sunlight to help destabilize the atmosphere further. The SPC notes in their outlook that vertical wind shear will increase as the trough approaches from the west.

The primary threat appears to be strong damaging winds and a risk of tornadoes. Bow-echoed thunderstorms can influence this threat. The timing appears to be very late afternoon to after dusk.

I'll do my best to write a blog post tomorrow afternoon to give another update on the situation in Florida. Keep an eye on my Twitter feed (@daweathaman) for the latest. Stay alert, my Florida friends.

Tuesday, January 18, 2011

Gloomy Day Ahead for Starkville

It's been a real ugly morning Starkville with low cloudcover and cool temperatures. This will persist during the day, but some slight clearing looks to be in order tonight.

The shortwave trough that brought the rain chances earlier in the weekend and the severe weather threat in south Florida yesterday is no longer a concern. A cold front associated with a low in southern Michigan is expected to pass later today into this evening. Most of the cloudcover will still remain tonight. However, as the low-level moisture begins to leave, so will the clouds and skies should begin to clear out tomorrow morning. NWS-JAN is hinting in their latest discussion that there could still be some "stubborn" cloudcover aloft tomorrow. Some of the model runs do leave it fairly dry aloft during Wednesday.

Expect the next weather update sometime tomorrow.

Monday, January 17, 2011

Severe Weather Threat in S FLA

As a graduate student in Mississippi, there are times when I miss Florida. I miss the proximity to the beaches, the family and friends. I miss the beauty of the state. I also miss the weather, and today is an example of that.

Aloft, a shortwave trough is digging into the Gulf of Mexico and is expected to progress west today. At the surface, the SPC notes a low west-southwest of Tampa that is expected to move east-northesast. Infrared satellite imagery hints at a sharp boundary with cooler cloudtops. Level II state radar shows showers over central Florida with a few potent cells entering northern Brevard County and another entering northern Manatee County. In fact, NWS-MLB has issued a tornado warning for northern Brevard and southeastern Orange counties until 11:45 AM EST.

There are a few factors that could enhance the severe weather threat this afternoon in south Florida...

- Approaching shortwave trough could enhance wind shear to allow for rotating thunderstorms. 12Z soundings from Miami already indicates some shear and things could enhance later today.
- Satellite imagery shows some clearing north of Miami and south of Tampa Bay. Daytime heating could help destabilize the atmosphere later today.

However, the SPC notes that large-scale rising air will not be too great, but there is a shot of long-lived updrafts locally. The SPC has just issued a tornado watch for Broward, Miami-Dade, Palm Beach, Monroe counties, and adjacent coastal waters (out to 20 NM) until 7 PM EST. The highest severe risk are strong winds and tornadoes. Based on a couple of storms I've seen this morning, bow echoes seem to be the culprit and the SPC is hinting at that continuing.

Keep any eye to the sky in south Florida. I'll do best to keep tabs on my Twitter account as the day wears on.

Sunday, January 16, 2011

Starkville: IT'S GON' RAIN!

Good Sunday, everyone. I know, I know. It's been nearly three months since my last weather blog post. The end of last semester was busy and very stressful. I'm going to try my best to make updates from here on out - but I can't make any guarantees.

My first piece of weather info I looked at this morning was all the green displayed on the regional radar imagery. Parts of Arkansas, Texas, and Louisiana are encountering moderate to heavy rain. This will make its way to The Golden Triangle area this afternoon.

Upper-air models are showing a shortwave trough over the Texas area that will progress west over the next day. Current observations and models are showing surface and 850-mb moisture levels increasing in Mississippi and points west. Infrared satellite imagery is showing what looks to be a baroclinic leaf, hinting the early stages of the developing low over eastern Texas.

As this storm continues to brew today, rainfall will start to move into the Starkville area and persist through the night. The 500-mb NAM and GFS are in good agreement of the shortwave trough's placement over Louisiana at 7 AM CST (12Z) Monday. Rain should start to taper off as the day progresses.

Rainfall doesn't seem that impressive according to the two-day HPC QPFs with only showing under a half-inch of precip for the area.

I hope to be back on the blog for a short update sometime Tuesday. Stay tuned.