Daweathablog

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

Friday, October 23, 2009

Kickoff Forecast: Florida vs Mississippi State

Here's another gameday forecast for a Florida game. This time, it's an away game at Mississippi State in Starkville.

Now (in Starkville)...
A cold front has passed the area and is currently over eastern Alabama. Winds are mostly out of the west across the region with temperatures in the 50s.

Saturday...
High pressure to the southwest and a west to northwest flow should help keep conditions really nice for the next couple of days. Models seem to indicate highs in the 60s with lows in the upper 30s for Saturday night / Sunday morning.

Kickoff...
With kickoff at 7:30 PM ET, the temperature should be near 56 with mostly sunny skies with temperatures falling quickly afterwards. In other words, jacket weather.

Those going to the game: Have fun, be safe, and Go Gators!

Saturday, October 17, 2009

Cooler Weather is Here!

Just got back in town from Orlando this evening after leaving Gainesville Friday to temps well above normal and very muggy. When we arrived in town, the temperature difference was highly noticeable. I was almost shocked. It has been so long since it has been this nice.

Now...

It's 52 degrees at Gainesville Regional Airport at the moment and 55 degrees at my apartment in southwest Gainesville. The cold front that passed Friday is just south of the Florida Keys while the low is offshore near 30 degrees north latitude. Dewpoints remain really low (in the 40s) with winds mostly from the northwest in inland Florida and points north. There is some high cloudiness to our north over southern Georgia.

Tonight...
Clear skies are over Gainesville with temps in the 50s, but the winds at 15 mph (sustained, 25 mph gusts at KGNV), it feels colder. The cloudcover over south Georgia is on it's way towards the area (it can been seen on the infrared satellite imagery and the last few frames of the visible).

There are two things that can make this forecast tricky tonight:

1) The wind. Wind may make it FEEL cold, but it could help keep the air temperature warmer than it would be if the winds were calm. This is because winds stir up any heat at the surface can keeps radiational cooling in check.

2) Cloudcover. This also keeps radiational cooling in check. It helps keep heat remaining in the troposphere (where all the weather occurs in the atmosphere) to escape back into space. In other words, cloudcover acts as a blanket over us and helps keep things warmer than it would be with clear skies.

NWS-JAX is calling for 41 tonight in Gainesville. However, am beginning to question this forecast a little. Cloudcover to our north may dissipate (as it is starting to show in the IR sat imagery). However, guidance models seem to have winds remain at around 10 knots (11.5 mph).

For tonight, partly cloudy skies for later on. Otherwise, mostly clear. I'm going to be slightly conservative at the moment and call for a low near 44.

If you plan on celebrating the win against Arkansas tonight (WoOt, Gators!) or going downtown, bring a nice coat.

Sunday looks really nice with clear skies and a high near 65. Sunday night might be the coldest night of during this spell. I'll post my predictions tomorrow evening on Twitter and Facebook.

Sunday, October 11, 2009

WHERE'S FALL??????

So, yea. For over a week, Florida has been under some ungodly weather for this time of year. Let's put things into perspective of where things should be in our area...

- Fall is usually considered in Florida when the average daily minimum temperatures fall below 60 degrees F. In Gainesville, it usually happens the second or third week of October (Winsberg, 2003). It's week two (approaching week 3) and we're still mostly in the 70s.
- The normal low for this morning is 61 (NOAA). It was 69 with dewpoints in the upper 60s.

In other words, it's been terrible.

What is happening now...
A stationary front is over the area with temps mostly in the 80s with showers and storms around the area. However, based on surface observations and the NWS-JAX discussion, the front appears to be diffused.

Next couple of days...
Fog could be an issue tomorrow since low-level moisture persists with the possibility of temperature inversions at some spots. On Monday and Tuesday, the HPC notes a wave of low pressure to move along the front (as it moves north during the next two days). Guidance models (NGM and GFS) show a continued surface and 850mb-level SE flow and should continue to bring in moisture. NWS-JAX notes that favorable dynamics aloft and shortwave energy could enhance thunderstorm development with a chance of a few strong ones. They have left the area at a 50-50 chance of rain Monday and 40 percent Tuesday.

Later this week...
It looks like the awful heat has a chance to vamos this weekend. A developing low is expect to bring the front back north. This low should be amplified by a upper trough that guidance models are picking up on over the southeast. The frontal passage, which could be Friday night/Saturday based on HPC surface forecasts, could bring some cooler weather to the area. However, NWS-JAX is hinting at a severe weather risk based on the possibility of a southwesterly low-level jet and sufficient instability. Time will tell whether this holds up - it's a little too early to call that threat.

In a nutshell...
Hot and gross for the next few days. Friday, good chance of storms with a cooler temps this weekend. We'll see how this forecast holds up.

Keep an eye on my Twitter updates for the latest.

Sources: Winsberg, Morton D. "Florida Weather, Second Edition" University Press of Florida, 2007

Saturday, October 10, 2009

Kickoff Forecast: Florida at LSU

Good morning from balmy north central Florida. It's 84 at my apartment complex and partly cloudy. It looks like we might get a chance of a shower or two this afternoon per NWS-JAX forecast. But I'm not writing to talk about Gainesville's weather. It's time to scope in on Baton Rouge, Louisiana for tonight's Florida and Louisiana State football game.

Currently, NWS radar from Slidell shows a southwest to northeast line of showers moving east and the last of it is passing over Baton Rouge. This is associated with a cold front that passed this morning. However, NWS-New Orleans notes in their AFD that the "frontal trough bisects the area and has stalled." This would help set the stage for the front to move back northeast and would create an environment for showers and thunderstorms later today and this evening.

Both the 0Z (8 pm EDT) NAM and GFS runs seem to show high precip over the area around 8 p.m. However, I am waiting on the 12Z runs to see how what they show and might give another update later today. GFS precipitable water amounts seem to creep back up from the south near kickoff.

It looks like chances are good that we could see some rain during the game this evening as this front pushes back a little this PM. I think that KBTR will not be in the warm sector and temps will remain slightly cool (for Florida standards); therefore, the temps should be around 66 at kickoff.

Kickoff forecast: Mostly cloudy with a good chance of showers. Temp: near 66.


I'll be at home with Erin and a friend watching the game in HD. I'll also be watching the radar. Keep an eye on my Twitter account for updates.

Go Gators!!

Wednesday, October 7, 2009

Summer in October

We had a nice shot of cold air last week, but now have it return back to this humid and hot weather - in October. What's the big deal?

For the last few days, the upper-air patterns have been locking colder air to the north and keeping the area pretty warm. Current 300-mb height maps show the jet stream to the north only bringing cooler air to parts of the northern Rocky Mountains and again over the central Great Lakes (per surface temperature map patterns).

(formula too complicated to put in "alt" tag

There is a high pressure system at the upper, mid and lower levels over the southeast and Gulf of Mexico. This is keeping things very warm, humid, but keeping rain chances relatively low for our area. The ridge is expected to move east over time and be out in the Atlantic waters Friday (models seem to be in agreement of this) and bring more of a southerly flow to the area.

Some amount of hope: NWS-Jacksonville is hinting at a cold front to approach the area and bring a chance of showers and storms to the area. One model, the ECMWF, is pushing the front to the south of Gainesville and bringing some cooler and drier air. NOGAPS seems to indicate a high pressure influence over the area on Tuesday. Models also show the upper trough (dip in the jet stream) to be in the mid Atlantic states Tuesday.

The Climate Prediction Center is also indicating below normal temperatures six to 10 days out for the eastern seaboard.

Right now, model guidance (remember the word "guidance") seems to give us a clue to possible relief from this October summer the we in North Central Florida have been experiencing. I'll keep watching it.

In the meantime, things seem to remain pretty balmy with summer-like conditions. Tonight, expect mostly clear skies with a low near 72. For Thursday, partly cloudy with a chance of a few stray showers. I'm expecting a high near 92. It will be moist with dewpoints hanging in the 70s and with precipitable water amounts near 2 inches.

Things may change in the next few days. Keep tabs on my Twitter account for the latest.