SW Louisiana Forecast Discussion...It was an absolutely beautiful day on Wednesday with high pressure in control in the wake of Monday Night's cold front. Humidity values were exceptionally low, and the sky was crystal clear with tons of sunshine. It was a refreshing start to the day with low temperatures in the mid 40s to lower 50s across the forecast area. Afternoon highs were more representative of seasonal values for late April with readings topping out in the lower 80s. This pleasant weather will be vacating the region over the next 24 hours, but it will remain fairly pleasant for the overnight hours with clear skies and a beautiful full moon in place. A light return flow has been established and as a result dew points and humidity values will increase, thus low temperatures will respond by only reaching more normal values with upper 50s to lower 60s logically obtainable.
The transition begins in earnest on Thursday. The controlling high at mid-week will continue its Eastward slide, and the resultant effects will be a more pronounced return flow of Gulf air. A long fetch Southerly flow will become established and bring back the low-level moisture with a vengeance. There will be no mention of rain on Thursday with the lack of a trigger mechanism, and the mid and upper levels remaining largely capped (remember what we talked about last week?). You will certainly ascertain that the humidity is back in full force by the afternoon hours. Temperatures will be similar to Wednesday with readings climbing into the lower 80s, but it won't feel near as nice thanks (or not) to the humidity. Skies will transition from Sunny early to Partly Cloudy with a good deal of cumulus clouds in place for the afternoon hours. The upper level capping begins to break down by Thursday night as another elongated trough and associated Pacific front encroach on the area. Rain chances will return to the forecast only slightly for Thursday night as the effects of the weakening cap and pooling Gulf moisture take effect. The pressure gradient will tighten across the area as well as cyclogenesis associated with the Pacific storm develops, and the squeeze play begin weather systems unravels over the forecast area. This will result in stiff Southerly breezes over 20 mph at times overnight Thursday. Any rainfall will be very scattered in nature, and nothing severe or overly heavy is expected for this period. Low temperatures will swing to above normal with only lower 70s expected for much of the area.
Rain chances ramp up on Friday, but that being said I should clarify that it will be on a scattered basis, and it will strictly be on a hit or miss basis as it stands right now. However, the atmospheric profile is one that will favor the possibility of severe weather. The weakening cap aloft should continue to wither as the potent Pacific storm punches more moisture into the upper atmosphere. There will be more than sufficient low-level moisture in place, and there is likely to be just enough convergence at the surface to generate the development of scattered showers and thunderstorms by Friday afternoon. The cold front associated with the approaching Pacific storm will likely stall out as it approaches, but it will certainly serve as a trigger mechanism to spark off the aforementioned shower and thunderstorm activity. Embedded disturbances in the long fetch SW flow will emanate out ahead of the main trough over the forecast area, and provide additional lift and instability. A strong Jet will also develop and stream from SW to NE across the NW Gulf Coast. All of this suggests that many of the parameters will be in place for some strong to severe thunderstorms to develop Friday afternoon. However, as previously stated the activity will be on a scattered nature, and there's certainly no way to pinpoint exactly who will get a severe storm much less rain in general in this pattern. The bottom line here is that all modes of severe weather will be possible across the entire forecast area, but the greatest risk should remain North of this forecast area. It is not clear cut and dry at this point if we'll see severe weather in SW Louisiana, but we certainly can't let our guard down. A supercell environment is favored in this set up, with the greatest threats from these storms being large hail and isolated tornadoes. Damaging winds can't be ruled out either. Temperature regimes will be well above normal with lows in the lower 70s, and highs in the low to mid 80s. Rain chances will be on the decent side, but not in the likely category (40%). We certainly need some rain, but don't need the severe weather. This is a situation that will be re-assessed on Thursday. This storm system will not be in a hurry to pass through as the cold front will stall out and its upper level support collapse due to the established steering currents across the country. What does this mean for the weekend?
There's a lot going on this weekend, including the first weekend of Contraband Days right here in Lake Charles. There is good news and bad news with regards to the weekend's outdoor plans. Rain chances will remain in the forecast, but it will likely not be a wash out by any means. The frontal boundary will be stalled out to our North, likely slicing through parts of the forecast area. The emanating disturbances will continue to spew out in response to the continued SW flow aloft, and ride up along the front. This means that scattered shower and thunderstorm activity is to be expected both Saturday and Sunday. Severe weather can't be ruled out either especially on Saturday when decent parameters will still be in place. However, the severe weather threat looks to lessen by Sunday. Model guidance suggests overall coverage should be about the same each day, but should be less than on Friday. Partly to Mostly Cloudy skies will be in store with very humid conditions are expected. The most likely time to see rain would be during the afternoon in response to the effects of daytime heating (almost like summer). The stalled front should wash out by Sunday, and this should lessen the severe chances. However, the presence of the long fetch SW flow will keep the periodic perturbations going, thus the continuation of rain chances. The temperature regime will be more representative of late May as opposed to early May with mid 70s for lows and highs in the mid to upper 80s area wide. This weather pattern will certainly not wash out all the outdoor events, but if you do have plans to attend Contraband Days, Fast Pitch 56, etc. you will want to bring your rain gear to be prepared. By all means, please seek immediate shelter once you see lightning or hear thunder! Again, the prospects of any severe weather during this time will be re-assessed Thursday.
A forecast of persistence is in order for the first part of next week. This reluctant pattern will remain in place until a secondary, stronger Pacific front comes through and clears everything out. When this occurs exactly remains to be seen. It seems doubtful that it will be Monday. Rain chances do ramp up more on Monday as the stronger front approaches, and Jet Stream energy is enhanced once again. Scattered convection is expected Monday, and the best chances should come on Tuesday as it stands right now. This seems to be the most likely day to see the frontal passage occur. Rain and storms could be likely on Tuesday, but it is too early to tell about severe weather during this period. Just understand that a prolonged period of rain chances is expected beginning Friday and lasting through Tuesday with daily variations on percentages expected. The temperature regime for the first part of next week will be a replay of the weekend. Sky conditions will be Partly to Mostly Cloudy with a daily dose of cumulus clouds expected. It is these a random selection of these cumulus clouds that will experience maturation and turn into thunderstorms primarily in the afternoon hours. The end of the forecast period on Wednesday looks quiet at this time. There is still some speculation as to whether or not the front will hold back and not pass through until Wednesday. For now, I will offer a solution that reflects a Tuesday frontal passage, thus keeping Wednesday nice with lower humidity and pleasantly warm temperatures. The front appears strong enough that some cooling will occur behind it with lows down into the lower 60s once again by the end of the forecast period, and highs around 80. Some 50s will be possible for lows just beyond the forecast period with a refreshing area of high pressure building into the region in the wake of Tuesday's front. Pleasant early May weather may close out the rest of next week with promising weather for Mother's Day weekend and the second big weekend of Contraband Days. Stay tuned for more!
Preliminary Numbers & Zone Forecast:
LCH 60/81 71/83 73/85 0 0 20 40 30 30
LFT 60/82 71/84 74/86 0 0 20 40 30 30
BPT 62/83 72/85 75/87 0 0 20 40 30 30
AEX 56/85 70/86 75/88 0 0 20 40 40 30
POE 57/84 71/85 75/87 0 0 20 40 40 30
ARA 60/80 72/83 75/84 0 0 20 40 30 30
Tonight...Mostly Clear and Not as Cool. Low 60. SSE wind 10 mph.
Thursday...Partly Cloudy & Breezy. High 81. SSE wind 15-20 mph and gusty.
Thursday Night...Mostly Cloudy with a 20% chance of showers & thunderstorms. Low 71. SSE winds 15-20 mph and gusty.
Friday...Partly to Mostly Cloudy & Windy with a 40% chance of showers & thunderstorms. Some severe weather possible in the afternoon. High 83. SSE wind 20-25 mph and gusty.
Friday Night...Partly to Mostly Cloudy with a 30% chance of showers & thunderstorms. Low 73. SSE wind 15-20 mph and gusty.
Saturday...Partly to Mostly Cloudy & Windy with a 30% chance of showers & thunderstorms. Some severe thunderstorms possible in the afternoon. High 85. SSE wind 20-25 mph and gusty.
Thursday 4/29/10 Daily Planner
6a.m.
Weather: Mostly Clear
Temp: 60
Rain: 0%
Wind: SSE 8
9a.m.
Weather: Mostly Sunny
Temp: 68
Rain: 0%
Wind: SSE 13
Noon
Weather: Partly Cloudy, Breezy
Temp: 75
Rain: 0%
Wind: SSE 17
3p.m.
Weather: Partly Cloudy, Breezy
Temp: 81
Rain: 0%
Wind: SSE 20
6p.m.
Weather: Partly Cloudy
Temp: 78
Rain: 0%
Wind: SSE 18
9p.m.
Weather: Mostly Cloudy
Temp: 76
Rain: 10%
Wind: SSE 14
Drew's 7 Day Outlook
Thursday
4-29-10
Low: 60
High: 81
Rain: 0%
Wind: SSE 15-20
Friday
4-30-10
Low: 71
High: 83
Rain: 40%
Wind: SSE 20-25
Saturday
5-1-10
Low: 73
High: 86
Rain: 30%
Wind: SSE 20-25
Sunday
5-2-10
Low: 75
High: 86
Rain: 30%
Wind: SSE 20-25
Monday
5-3-10
Low: 75
High: 85
Rain: 50%
Wind: SSE 20-25
Tuesday
5-4-10
Low: 73
High: 82
Rain: 60%
Wind: SSW 20-25
Wednesday
5-5-10
Low: 60
High: 78
Rain: 0%
Wind: NNW 10-15
...Marine Forecast...
Tonight...South winds 10 to 15 knots. Seas 2 to 4 feet.
Thursday...Southeast winds 15 to 20 knots. Seas 3 to 5 feet.
Thursday Night...Southeast winds 15 to 20 knots. Seas 4 to 6 feet. A slight chance of showers.
Friday...South winds around 20 knots. Seas 5 to 6 feet. A slight chance of showers and thunderstorms.
Friday Night...South winds 15 to 20 knots. Seas 5 to 6 feet. A slight chance of showers and thunderstorms.
Saturday...South winds 15 to 20 knots. Seas 4 to 6 feet. A slight chance of showers and thunderstorms.
...Tide Data...
Thursday Tides @ Calcasieu Pass
Low: 11:45a.m. 10:13p.m.
High: 4:51a.m. 1:08p.m.
...Toledo Bend Pool Level...
170.69'
...Lake Charles Climate Summary...
Wednesday, April 28, 2010
Low: 51
Normal Low: 60
Record Low: 40-1920
High: 81
Normal High: 80
Record High: 95-1987
Rainfall
Today: 0.00"
Month to Date: 0.11"
Normal Month to Date: 3.34"
Year to Date: 9.39"
Normal Year to Date: 15.68"
Record: 7.65"-1914
Sensible Weather Observed Today:
None
One Year Ago (2009)
Low: 65
High: 82
Rain: 0.18"
5 Years Ago (2005)
Low: 57
High: 81
Rain: 0.00"
10 Years Ago (2000)
Low: 58
High: 87
Rain: 0.00"
Sunrise Thursday: 6:32a.m.
Sunset Thursday: 7:49p.m.
...Lunar Table...
Full Moon- Tonight April 28
Last Quarter- Thursday May 6
New Moon- Friday May 14
First Quarter- Thursday May 20
Have a Great Thursday & God bless!
-DM-
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