Thursday, October 8, 2009
SW Louisiana Forecast Discussion...Unseasonable warmth and humid conditions continued as advertised today as a pronounced onshore flow continued off the Gulf as we await the advancing trough. Shower and thunderstorm activity was limited during the afternoon hours thanks to some drier air in the mid and upper levels. This "cap" is still present tonight, and therefore, no mention of rain is expected as the offshore flow continues. It will be non-eventful night across the area with Partly to Mostly Cloudy and the unseasonable warmth in place. Pressure differences created by the advancing trough will keep winds from dying off as they usually do overnight. This will preclude the development of any fog, and keep enough mixing going in the atmosphere that no more than a low-cloud deck should be present. While it will be quiet here overnight, we turn our attention upstream for a harbinger of things to come.
At present, the front is in transit from NW to SE across the Mid West and Red River Valley. Heavy rainfall with localized flooding and some severe weather has occurred today and tonight from Texas to Missouri. Severe Weather Watch boxes are currently posted along and out ahead of the front from the Rio Grande Valley up through the Ohio River Valley. A pre-frontal MCS (squall line) developed during the day today, and is still currently active at this time. It is advancing to the SE as the trough and attendant cold front dig further South as well. The weather around here will remain rather benign for the early part of Friday with no rain expected across the area until the afternoon hours, most likely from around 3p.m. and on. It will be windy and Mostly Cloudy with above normal temperatures once again for the day on Friday with highs in the mid 80s. The MCS will move into the Northern portions of the state during the morning hours, and continue to move SE into our area in the afternoon, however, as the front moves SE the upper level supporting winds driving the front will not be near as strong, and it will be bumping up against the persistent SW flow over the Gulf of Mexico. As a result, the front will be in the process of slowing down, therefore, the associated MCS will be as well. This means that a heavy rainfall event seems likely. It remains to be seen if we will have a severe weather threat across the forecast area, but that possibility exists as well. Some very potent dynamics have been generated by this system, and with extra energy from the Jet Stream in an El Nino pattern, some severe weather is possible. The main threat at this time looks to be damaging winds, but hail and an isolated tornado are possible as well. The greatest threat for severe weather should remain off towards our North, but as it stands at the moment the SPC has the entire forecast area highlighted for a Slight Risk of Severe Weather for Day 2 (Friday). Stay tuned for more on this.
Regardless of any severe weather, rain and thunderstorms are inevitable for later in the day Friday through Friday night, and the timing of this is very unfortunate with all the High School Football games. The current timing for the worst of the weather suggested by the forecast models looks to be in a time frame of 6-9p.m. Lightning will be a problem, and many of the games could be delayed. It will likely rain for several hours with a large area of rain and embedded thunderstorms trailing behind the MCS. Some scattered shower and thunderstorm activity is expected to develop out ahead of the complex of storms as the system feeds on the highly moist environment and pulls in additional moisture from the Gulf. Heavy rainfall is the most significant weather problem that I expect for our area with this system. Average rainfall amounts as shown by Thursday evening model guidance shows 2-4" of rain area wide from Friday afternoon through Saturday night. The front will slowly move through the forecast area between sunset Friday and sunrise Saturday, and it will turn sharply cooler behind it. It will be windy before and after frontal passage, but winds will shift from onshore to offshore with as the boundary passes. Overnight lows will be 10-15 cooler than that of recent nights with lows well down into the 60s by Saturday morning. While the front will put an end to the unseasonable warmth, it will not put an end to the rain chances. Here's a look at the SPC's Day 2 Outlook:
The forecast for the weekend certainly leaves something to be desired for those who want some of that picture perfect low-humidity October weather that often follows these fronts this time of year.. An overrunning situation is almost certain behind the front as the front continues to slow down, and eventually stall over the Gulf of Mexico in response to the strong SW flow. A secondary push of cooler, drier air will remain North of the area as the winds aloft remain parallel to the frontal boundary. This never bodes well for beautiful weather across the area. Overcast conditions will remain firmly entrenched, and rain chances will remain high for the Saturday forecast period as well. Rain could be heavy at times, but overall mostly a light rain or drizzle is expected. Rain will come and go, and it won't be a situation where it rains all day. Disturbances embedded in the SW flow aloft will ride up along the front ejecting out of South Texas, and bring rain to the area. Rain will be likely throughout the day, but the best chance will be during the morning with a break possible during the afternoon only to see another period of rain Saturday night. That's right, looks like it's gonna be wet for the big LSU-Florida game in Baton Rouge, at the very least a wet field. I would suggest bringing the rain gear with you along with your "Gator" traps. Geaux Tigers!!! Not to be forgotten, McNeese plays on the road this weekend as well vs. SFA up in Nacogdoches, TX, and the forecast is much of the same up there. Though, the chance of rain will be less since they will be further removed from the stalled front. Geaux Cowboys!!! The temperature part of the forecast is the good news as it will be much cooler in the wake of this shallow cold front. Highs will struggle to reach 70 on Saturday, and at this time I am forecasting a maximum somewhere in the low 70s. Brisk Northerly winds will make it feel like it's in the 60s throughout the day, so with the rain it will certainly not be the best looking Saturday. One of these weekends, Mother Nature is going to pay us back you know.
The Saturday night through Sunday period will continue to a cool, overcast period with intermittent rain and/or drizzle likely Saturday night. Temperatures will fall into the upper 50s to lower 60s. On Sunday, rain remains likely and may actually be heavy at times if models are correct in the idea of cyclogenesis along the stalled front in the Gulf. This would occur off the coast of South Texas, and traverse the front from SW to NE. This would allow for moisture over the Gulf to be pulled Northward over the area keeping the rain chances in the forecast. The low will help to generate instability in the atmosphere thus resulting in the possibly of heavy rain and/or thunderstorms at times Sunday. An additional 1-2" of rain is possible Sunday, and this could certainly pose a flooding threat across the area by that time with grounds nearly saturated from recent rains and the warm, moist air that has dominated this week. The cool air at the surface will remain in place with highs only in the mid 70s, still below the seasonable norm for the 2nd week of October. Rain will be more likely from late morning through mid afternoon Sunday before tapering off.
How often do you see the weather improve just as its time to go back to work or school on Monday? Not this time! Monday's weather offers a continuance of the weekend weather pattern with rain off and on throughout the day as the overrunning effect continues with the front wavering one way or the other in the Gulf. The cool air mass in place from the weekend will begin to moderate somewhat as the strong Canadian high pressure slides to the NE out of the Ozarks and into the Ohio Valley. Near average temperatures are expected for both lows and highs. Improvement takes place for the Tuesday-Thursday time frame as the winds at the surface take on a Southerly component to match the upper level winds in between cold fronts. The forecast models waver on how much clearing we'll see, and if we'll see any rain chances at all. At this point, it seems logical to keep a slight chance of showers in the forecast with a wording of Partly Cloudy for sky conditions. Temperatures are also a crapshoot at this time as some model output shows temperatures returning to above normal levels, while some keep the moderation more subtle. I will blend these forecasts and keep temperatures around seasonable values for both highs and lows by the end of the forecast period. The next cold front doesn't look to affect the area until just beyond this forecast period. Stay tuned for all the latest on the severe weather and heavy rainfall potential on Friday.
Tropics: Quiet. Henri, as forecast, had a very short life in the open Atlantic near the Lesser Antilles. He has fizzled out completely tonight with nothing more than an area of cloudiness to represent his remnants. The highly sheared environment over the Atlantic ingested Henri, and we can write his obituary. A tropical wave in the Southern Caribbean is not expected to develop as it is very close to the NE coast of Venezuela, and will interact with that country on Friday. Some slow development of this system is possible over the weekend as it pulls away from South America into the middle of the Caribbean, but like many of its predecessors this season it will ultimately suffer the same fate and run into a highly sheared environment.
Preliminary Numbers & Zone Forecast:
LCH 78/86 63/71 60/74 10 80 100 70 60 60
LFT 77/87 63/72 59/73 10 70 100 80 60 60
BPT 79/85 62/70 60/75 10 80 100 80 60 50
AEX 76/84 58/68 55/70 10 90 100 80 60 40
POE 76/85 59/69 56/70 10 90 100 80 60 40
ARA 80/87 64/73 62/73 10 70 100 80 70 70
Tonight...Partly to Mostly Cloudy and Unseasonably Warm. Low 78. SSE wind 10-15 mph.
Friday...Mostly Cloudy and Windy with Showers and Thunderstorms Likely in the afternoon. Heavy rainfall likely and Damaging winds possible. High 86. SSW wind 15-20 mph and gusty. Chance of rain 80%.
Friday Night...Cloudy with Showers and Thunderstorms Likely. Isolated severe storms possible with damaging wind the main threat. Heavy rainfall likely with 2-4' of rainfall expected. Turning Cooler overnight. Low 63. SSW wind 15-20 mph and gusty, becoming NNW at 15-20 mph and gusty by midnight. Chance of rain 100%.
Saturday...Cloudy with Rain Likely. Much Cooler. High 71. North wind 10-15 mph. Chance of rain 70%.
Saturday Night...Cloudy and Cool with Rain Likely. Low 60. NE wind 10 mph. Chance of rain 60%.
Sunday...Cloudy with Rain and a Few Thunderstorms Likely. High 74. NE wind 10-15 mph. Chance of rain 60%.
7 Day Outlook for Lake Charles & Vicinity
Friday
10-9-09
Low: 76
High: 86
Precip: 80%
Wind: SSW 15-20
Saturday
10-10-09
Low: 63
High: 71
Precip: 70%
Wind: N 10-15
Sunday
10-11-09
Low: 60
High: 74
Precip: 60%
Wind: NE 10-15
Monday
10-12-09
Low: 62
High: 78
Preci:p: 40%
Wind: E 10-15
Tuesday
10-13-09
Low: 66
High: 82
Precip: 30%
Wind: SE 10-15
Wednesday
10-14-09
Low: 65
High: 80
Precip: 20%
Wind: SW 10-15
Thursday
10-15-09
Low: 63
High: 81
Precip: 20%
Wind: SW 10-15
...Marine...
Friday...South winds 15 to 20 knots decreasing to 10 to 15 knots in the afternoon. Seas 2 to 4 feet. A chance of showers and thunderstorms in the morning...then showers and thunderstorms likely in the afternoon.
Friday Night...Southwest winds 10 to 15 knots becoming northwest after midnight. Seas 2 to 3 feet. Showers and thunderstorms likely in the evening...then a chance of showers and thunderstorms after midnight.
Saturday...Northeast winds 5 to 10 knots. Seas 2 to 3 feet subsiding to 1 to 2 feet in the afternoon. A chance of showers and isolated thunderstorms.
Saturday Night...Northeast winds 10 to 15 knots. Seas 1 to 2 feet. A chance of showers and thunderstorms.
Sunday...East winds around 10 knots. Seas 1 to 2 feet. A chance of showers and thunderstorms.
Tide Data...
Friday Tides...
Low: 12:54p.m.
High: 1:56a.m.
Lake Charles Climate Summary...
Thursday, October 8, 2009
Low: 81
Normal Low: 61
Record Low: 40-1952
High: 91
Normal High: 83
Record High: 96-1911
Rainfall:
Today: 0.00"
Month to Date: 3.10"
Normal Month to Date: 1.17"
Year to Date: 50.08"
Normal Year to Date: 45.21"
Record: 1.63"
Sunrise Friday: 7:11a.m.
Sunset Friday: 6:48p.m.
Good night and God bless!!!
-DM-
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