SW Louisiana Forecast Discussion...Rain will begin overnight. It was a day of transition across the forecast area. Clouds gradually increased throughout the day as the advertised vigorous storm system approaches. Some sunshine occurred this morning, but overcast conditions moved in by mid afternoon across the forecast area. Mild weather continued for another day with a high in the upper 60s to around 70. A pronounced Gulf flow was established as well as the pressure gradient force strengthened across the area. This latest system is still getting better organized over the Central Plains into West Texas. A significant ice/snow storm will occur over that area through Friday. All precipitation will be liquid here. Overnight, showers will begin to develop across the area as deeper moisture streams over the area ahead of the advancing storm. This vigorous storm system has multiple components associated with it. A surface low and trailing cold front is present over Texas, while a weak warm front is lifting Northward through the state tonight. The driving force behind this system is the strong upper level low which currently hangs back over New Mexico. All this will conglomerate and produce rain across the area from later tonight through Friday. The mild weather will continue tonight with lows only dropping into the mid to upper 50s. This is the last stretch with above normal temperatures for a little while.
Rain will be scattered and light initially, but by morning widespread rain will develop across the forecast area Heavy rain is expected at times, and some localized street flooding can't be ruled out Friday morning. This is a very dynamic and energetic system as the nose of strong low-level Jet will be moving across the area Friday. However, that being said, severe weather still appears to be a minimal threat. The strong Jet in place and projected atmospheric wind profiles does suggest some damaging winds are possible However, the greatest threat of any severe weather should be towards Acadiana. Heavy rainfall will be the biggest threat with this system, and not much change in forecast reasoning has occurred since we last spoke. As of this writing, showers have begun to develop near the coast, and are riding NE across the forecast area. This is an advance of the cold front which will cross the area on Friday. An MCS is likely to move through the area during the morning hours on Friday. The models are in fair agreement on the ETA of the front. It should enter the forecast area by mid-morning Friday, and reach Lake Charles around noon, and Acadiana by 3p.m. The heaviest rain should occur between the hours of 6a.m.- noon in the Lake Charles area as the front approaches. This will be the time frame when the best convergence and dynamics will be present. Rainfall won't come to an end with the frontal passage. there will be a period of overrunning rains behind the front for the remainder of the day on Friday. However, we will transition from a heavy rain threat to more of a light rain and/or drizzle situation. Average rainfall amounts still look be from 1-2" with higher amounts near 3" possible. We should be able to withstand these rain amounts and avoid a significant flooding event. However, some localized street flooding and flooding of low-lying areas can't be ruled out. Rain chances are maxed out for Friday. The mild weather will continue until frontal passage. Temperatures could reach the low end of the 60s before said frontal passage, but once the front comes through temperatures will hit the downward spiral. This is absolutely reflected in the forecast, and you may have noticed this throughout the week, that I've put the low as the high and the high as the low. Temperatures will fall from around 60 Friday morning into the 40s by Friday late afternoon as strong CAA takes over and Arctic air filters into the region. The big winter storm will continue off towards our North.
As mentioned a moment ago, there will be post-frontal rain across the area as a stint of overrunning will occur across the forecast area as the drier air in the mid and upper levels lags behind due to the shallow nature of the cold air. Temperatures will continue to fall into the 40s, and it will become quite raw by Friday evening. Winds will be an issue as well thanks to strong CAA. Winds will shift with fropa from SE to NNW and increase to over 20 mph at times. As temperatures fall into the 40s, a wind chill will come into play. Expect it to feel like the 30s by day's end. Wrap-around moisture will continue the threat for light rain/drizzle through the evening hours, making for a miserable Friday evening and Friday night. CAA will continue with temperatures falling into the 30s overnight, but all precipitation should remain liquid around these parts. North Louisiana could see some sleet or snow flurries before the precip ends early Saturday morning, but the prospects of frozen precip are even an iffy proposition up there. The overrunning, wrap-around moisture will keep cloud cover in place into Saturday. However, drier air will finally move into all levels of the atmosphere, thus ending the intermittent light rain and/or drizzle by this time. A definite reminder that it is still winter is inevitable at this time. Overnight minimums should range from the mid to upper 30s across the forecast area.
The weather improves on Saturday, and a dry weekend is anticipated. Although, it will be dry, it will be cold. Temperatures will be below normal through the weekend. Saturday will likely start out cloudy, but it should clear up during the day as Arctic high pressure infiltrates the region from the Red River Valley. It is prudent to undercut temperatures from what guidance shows based on the fact that the air over the region will be transported straight from the ice and snow pack to our North over Oklahoma via strong NNW winds. The continued CAA will offset significant warming, and a small diurnal is expected. I only expect temperatures to reach the mid 40s at best. Wind chills will be in the 20s by Saturday morning, and be in the 30s for the afternoon hours. Winds will decouple Saturday night as the high slides into SE and Central Texas. Skies will be clear, and this will set the stage for radiational cooling. The end result will be an area wide freeze for Saturday Night/Sunday Morning. However, hard freeze conditions should not be met. Temperatures will range from the mid 20s around POE and AEX to around 29 or 30 at LCH and LFT, while it should right at freezing along the coast by sunrise Sunday. We'll close out the month on Sunday with cold sunshine. This will make it a clean sweep for Sundays in the month of January...that is, 5 straight Sundays of beautiful weather o start the year. It will certainly be cold, but nothing like the blast of three weeks ago when we experienced 10s for the first time in 14 years. Sunday highs should rebound to the upper 40s to around 50 with high pressure in place. Clear and cold weather continues Sunday night, though air mass modification takes shape as the controlling high orients itself NE of the area. Lows heading into Monday should be around freezing.
As we start February, the weather starts changing once again. There's rarely a dull moment around these parts with the ongoing El Nino. February is often a month of transition around here. Initially, we can still see some very cold air during the first half of the month, however, by the second half of the month, severe weather season gets an early start across South Louisiana. No telling what is in store for February 2010, but here's what we should expect for the first week of the new month. Relatively benign weather is on tap for Monday, though the eroding Arctic air mass will keep it on the cool side. At the same time, an active Subtropical Jet Stream will be present. This will result in an increasing cirrus cloud canopy during the day. Disturbances permeating through the STJ will effect the area through the week. The first of these said disturbances should rotate through by Monday night bringing a slight chance of a shower, moisture should still be limited at this time, and there will be very limited instability to work with. It is mainly the forcing from these short waves that will kick off a shower or two Monday Night and ring up the available moisture. Monday during the day should be dry with just the aforementioned clouds rolling in. Highs should remain below seasonal values in the low to mid 50s.
Rain chances will increase further on Tuesday as a stronger short wave emanates the STJ, and ejects out ahead of an advancing trough dropping into the Intermountain West. Better lift and forcing will be in place to generate a decent chance of rain. However, it is near impossible to pinpoint the exact timing of these disturbances especially this far out, so determining whether or not the highest chance of rain will come during the morning or afternoon is no easy feat this far out. The bottom line is that an unsettled weather pattern is hanging in the balance for next week. A progressive warm up will carry us through the week, and temperatures will be closer to normal on Tuesday. You can expect more of the same on Wednesday. A more pronounced Gulf flow will be established at this time as a deepening trough approaches along with its associated strong cold front. Energy supplied by our nemesis STJ will continue to induce embedded perturbations that will trigger decent rain chances. By this time frame, enough instability could be generated for some thunderstorms, but I won't reflect that at this time. Temperatures moderate to near seasonal norms by mid week as the Gulf flow becomes entrenched. At this time, it appears that day 7, Thursday, will offer the worst weather for next week. A strong cold front should push through bringing with it the chance for some bodacious boomers. It is conceivable in this pattern, that we'll be entrenched in a warm sector set up ahead of the front. A more robust warm up is anticipated ahead of this next storm system. Temperatures should reach above normal levels. A heavy rainfall event will be possible along with the severe weather potential. The end of next week into Super Bowl weekend looks great right now. Conditions could be a bit chilly, but dry is the name of the game as we get ready to cheer the Saints onto victory over the Colts a week from Sunday! I still see the signs of another Arctic blast in early February, but certainly won't be specific about any details on that at this juncture.
Preliminary Numbers & Zone Forecast:
LCH 58/44 34/45 28/48 60 100 30 0 0 0
LFT 60/46 35/44 27/49 60 100 30 0 0 0
BPT 59/43 36/46 29/50 70 100 30 0 0 0
AEX 57/39 30/42 25/45 70 100 30 0 0 0
POE 56/41 32/43 26/46 70 100 30 0 0 0
ARA 61/46 36/46 28/49 60 100 30 0 0 0
Tonight...Cloudy with rain and a a few thunderstorms likely. Rain heavy at times towards morning. Temperatures near steady or slowly rise overnight from the upper 50s. SSE wind 10-15 mph. Chance of rain 60%.
Friday...Showers and thunderstorms likely in the morning. Gusty winds and heavy rainfall expected in the morning. No severe weather expected. 1-2" of rainfall expected with isolated 3" amounts possible. Rainfall transitioning to light rain and/or drizzle in the afternoon. High in the upper 50s to near 60 in the morning with temperatures falling into the 40s in the afternoon. SSE wind 15-20 mph and gusty in the morning, becoming NNW at 20-25 mph and gusty. Chance of rain 100%.
Friday Night..Cloudy, Windy, and Cold with a 30% chance of light rain and/or drizzle before midnight. Light rain and/or drizzle ending and skies clearing after midnight. Low 34. NNW wind 15-20 mph and gusty. Wind chills in the 20s.
Saturday...Becoming Sunny and Cold. High 45. NNW wind 10-15 mph.
Saturday Night...Clear and Cold with an area wide freeze. Low 28. Light North wind.
Sunday...Sunny and Cold. High 48. NE wind 5-10 mph.
Drew's 7 Day Outlook for Lake Charles & Vicinity
Friday
1-29-10
Low: 58
High: 44
Precip: 100%
Wind: SSE/NNW 15-25
Saturday
1-30-10
Low: 34
High: 45
Precip: 0%
Wind: NNW 10-15
W.C.: 20-35
Sunday
1-31-10
Low: 28
High: 48
Precip: 0%
Wind: NE 5-10
W.C.: 25-35
Monday
2-1-10
Low: 32
High: 53
Precip: 0%
Wind: NE 10
Tuesday
2-2-10
Groundhog Day
Low: 39
High: 56
Precip: 40%
Wind: NE 5-10
Wednesday
2-3-10
Low: 43
High: 58
Precip: 40%
Wind: ESE 10-15
Thursday
2-4-10
Low: 48
High: 64
Precip: 70%
Wind: SSE 10-15
...Marine Forecast...
*Small Craft Advisory in effect through Saturday.*
Friday...South winds around 20 knots becoming west in the afternoon. Seas 4 to 5 feet subsiding to 3 to 5 feet in the afternoon. Showers and thunderstorms.
Friday Night...Northwest winds 15 to 20 knots. Seas 3 to 5 feet.
Saturday...North winds 15 to 20 knots. Seas 2 to 4 feet.
Saturday Night...North winds 10 to 15 knots. Seas 2 to 3 feet.
Sunday...East winds 10 to 15 knots. Seas 1 to 3 feet.
Good night and God bless!
-DM-
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