SW Louisiana Forecast Discussion...The new work week got off to a wet start as the first of the three weather systems to affect our area this week moved through in the early morning hours. The rain associated with that system vacated the area before sunrise leaving us with Overcast and damp conditions for much of the day. Temperatures didn't move a whole lot with the maximum reaching the lower 60s around noon, before falling back into the 50s. The drying trend behind the morning rain lasted only a few hours as the next more robust system begins to affect the area. Showers began around 3p.m., and have persisted since that time. Rain has been heavy at times this evening, and this trend will continue overnight. It is all part of a system which is very rich in dynamics.
The cool front associated with the morning rain has stalled in the offshore waters. It will begin to retreat Northward overnight, and surge into inland areas as a warm front. As this boundary lifts Northward expect showers and a few thunderstorms to continue much of the night. A break will occur late tonight as the front moves onshore and through the area. The heaviest rainfall at present is over Acadiana, and this area may see the highest rainfall totals with this amount. Lighter and more scattered rain is ongoing points Westward including here in Lake Charles as of 10p.m. Dense fog may become an issue late tonight especially near the coast as deep low-level moisture will be in place in response to strong WAA across the area. Temperatures currently in the mid to upper 50s in Lake Charles & Vicinity will more than likely rise overnight with the WAA pattern established. When temperatures rise during the night, it is often a tricky forecast. Lows will likely occur at midnight before rising through the night into the 60s. At the same time that a WAA pattern is being established across the forecast area, the next major weather maker is just getting cranked up out West. This is what we will contend with on Tuesday.
Tuesday should dawn as a humid and potentially foggy day. Some scattered showers are possible with the deep moisture in place, and much of the area in the warm sector at this point. The higher threat for rain during the early morning hours should be over Northern sections of the area which may not quite be in the warm sector just yet. A largely amplified trough is diving Southward along the Polar Jet into the Great Plains, and a strong disturbance (short wave) embedded in the zonal flow and Subtropical Jet Stream currently over Southern California moves quickly to the East. This is in response to a very fast upper level flow across the country. The strong short wave and trough has brought very active weather out West with rain in the Los Angeles area, and snow in the mountains East of the nation's second largest city. Other energy embedded in the Subtropical Jet out ahead of the main upper level kicker is producing winter precipitation across the Texas and Oklahoma Panhandles, and this will be a big winter storm for the Great Plains and into the Mid West over the next couple of days. Back home, we will continue with heavy rain and thunderstorms on Tuesday as the trough digs and approaches our area bringing its associated cold front with it. The warm sector will continue to move inland. The moist unstable air mass in place and the generated instability out ahead of the cold front will lead to the development of showers and thunderstorms. Some of the thunderstorms could reach severe limits mainly from about 10a.m. to 4p.m. Tuesday. This is in correlation to the time of day when we see the greatest amount of convective heating potential. Temperatures in the warm sector will be near 70, above normal for early December to say the least. The main threats appear to be damaging winds and isolated tornadoes, though I feel that the tornado threat will be somewhat limited across the forecast area due to less than impressive instability. The shear needed to generate tornadoes will be present as strong surface winds from the SE increase ahead of the advancing system, while SW winds aloft also strengthening. The entire forecast area is highlighted for a Slight Risk of Severe Weather for Day 2 (Tuesday) by the Storm Prediction Center. The graphical representation of this is included below.
The best threat for severe weather will come in the afternoon hours of a surface low in response to the deepening trough advances to the NE from the Panhandle region of Texas and Oklahoma into Missouri. This will create the necessary convergence to produce shower and thunderstorm activity across the area, and the formation of a squall line (MCS) of showers and thunderstorms is expected along the front across Texas and it dips SE towards the forecast area. The warm sector environment in place across our area at this time will lead to additional shower and thunderstorm development out ahead of the MCS, and it is often these individual thunderstorms (supercells) that have a greater chance of exceeding severe limits. With expected strong vertical shear in place, some supercellular development is possible. One inhibiting factor will be the persistent cloud cover with little or no sunshine. The whole system will work in tandem and move Eastward across the forecast area Tuesday afternoon. Our area will be on the tail end of much of the activity, and I certainly expect the best dynamics to remain north of our area. While it is a marginal situation as far as severe weather is concerned, I am more concerned with the threat of heavy rain. Localized flooding certainly seems likely with all the rain we've had lately, and if the expected amounts of 1-3" comes to fruition Tuesday. Moisture will stream in off the Gulf throughout the day, and it is possible that heavy rain could train over the same areas leading to several inches of rain across the forecast area. A graphical representation of expected rainfall is shown below as well. All the rain and thunderstorms will end from West to East by late Tuesday afternoon as the cold front pushes through, and drier and cooler air is ushered into the forecast area. The entire system should be a quick mover, and I expect the front to enter the forecast area around 2p.m. reaching Lake Charles between 4 and 5p.m.,and between 6 and 7p.m. for Lafayette and New Iberia. The front should exit the entire area by 3Z Wednesday (9p.m. Tuesday). After temperatures into the 70s on Tuesday, a cooler air mass takes over Tuesday night with lows down into the 50s for Wednesday morning. There's a lot of Arctic air coming down into the country out of Canada behind this system, but we will only get a glancing blow as the overall pattern doesn't favor this Arctic air making it all the way to the Gulf coast.
The progressive pattern will remain with us for the foreseeable future. Some nice weather is on tap for the Wednesday/Thursday time frame with very little change in the forecast philosophy since last night's package. High pressure controls the weather across the area, and temperatures will return to below normal levels with just the glancing blow from the Arctic air to the North. CAA becomes more pronounced on Wednesday, and high temperatures will struggle to reach 60, but skies should be nice and sunny. It'll feel very much like it ought to feel in early December. The coldest period of the week comes on Wednesday night/Thursday morning when temperatures will easily reach the 30s once again as the glancing blow of Arctic air is experienced. Some 20s are possible for the coldest locations across the forecast area, but either way it'll be a cold start to the day on Thursday. I am forecasting 34 for Lake Charles at the moment, so not quite a freeze, but certainly in the frosty category. Thursday will continue to be dry, but it will also be cool as highs only reach the mid to upper 50s. The brief respite in between weather systems will be nice, because things go sour on us again for Friday.
The pattern we've seen all too often so far this fall will repeat itself as the work week draws to a close Friday. Clouds will increase in earnest Thursday night as cyclogenesis occurs off the South Texas coast, and another trough deepens in the Great Plains, driving its cold front into the area underneath a flattening upper level flow. After a temporary switch back to a NW flow, the flow will transition back to zonal. An ensuing modification of temperatures will occur. As the controlling high shifts East, winds will return to off the Gulf, and temperature moderation is a given. Friday morning minimums will be in the upper 30s to lower 40s...about 10 degrees warmer than that of Thursday morning. This next El Nino weather system will bring rain back to the forecast are during the day Friday. This one was doesn't appear to be near as robust is the one that is currently impinging on the area. Nevertheless, rain chances are in the forecast once again for Friday. We should remain in the cool sector with this system, so no severe weather is expected. Highs will remain on the cool side. Really, after Tuesday, temperatures for the remainder of the forecast period should be cool.
For the weekend, it really doesn't look too bad. Friday's system will depart and become an East coast problem over the weekend. Rapid clearing should occur early Saturday as the fast upper level flow continues. Cold Arctic air will remain entrenched just our North, but there is no sign of a major swift in the upper level air pattern that would allow the Arctic air to reach us. In fact, modification should ensue over the weekend as the predominantly zonal flow becomes established. Dry and pleasant weather is expected for the majority of the weekend with skies becoming sunny Saturday. Sunday should be a nice day as well. Seasonable temperatures are expected for the weekend with lows in the 40s on Saturday and highs in the lower 60s. Seasonably chilly conditions are expected for Sunday morning as high pressure settles right over our general vicinity. Mid to upper 30s should suffice for Sunday with a rebound into the mid 60s for afternoon highs. The next rain chance returns on Monday as the extremely progressive remains in place. It is too early to pin down specifics of this system, and discuss how strong it will be as models offer an array of solutions on this, but thre is considerable agreement in another similar system for this time frame, thus rain chances are warranted at this time for the day 7 period. If the long range projections are right, we'll be wishing for snow by mid-month as all the extremely cold air should remain bottled up to our North. The pattern will shift at some point, and we'll head into the deep freeze down the road, but that doesn't look like it'll be within the next two weeks or so. Stay tuned for the severe potential on Tuesday!
This Date in History...December 7, 1941...The Japanese attacked Pearl Harbor. It resulted in the United States entry into World War II. The attack consisted of two aerial attack waves totaling 353 aircraft, launched from six Japanese aircraft carriers.
The attack sank four U.S. Navy battleships, and damaged four others. Three cruisers, three destroyers, and one minelayer were also sunk or damaged by the Japanese. In all the attack by the Japanese, destroyed 188 aircraft, and caused personnel losses of 2,402 killed and 1,282 wounded. The power station, shipyard, maintenance, and fuel and torpedo storage facilities, as well as the submarine piers and headquarters building were not hit. Japanese losses were minimal, with 29 aircraft and five midget submarines lost, and 65 servicemen killed or wounded. One Japanese sailor was captured.
The attack was a major engagement of World War II. It took place before a formal declaration of war by Japan and before the last part of a 14-part message had been delivered to the State Department in Washington, D.C. The Japanese Embassy in Washington had been instructed to deliver it immediately prior to the scheduled time of the attack in Hawaii. Despite numerous historical precedents of unannounced military action, the lack of any formal declaration prior to the attack led President Franklin D. Roosevelt to proclaim..."December 7, 1941---a date which will live in infamy."
-Wikipedia
This Date in History 2: December 7, 1935...Severe flooding hit parts of the Houston, TX, area. Eight persons were killed as one hundred city blocks were inundated. Satsuma reported 16.49 inches of rain. The Buffalo and White Oak Bayous crested on the 9th. (6th-8th)
-The Weather Channel
Preliminary Numbers & Zone Forecast:
LCH 56/73 53/60 35/55 80 80 30 0 0 0
LFT 61/74 55/62 34/56 90 80 40 0 0 0
BPT 57/73 54/59 36/57 70 80 20 0 0 0
AEX 50/64 47/55 28/52 90 90 20 0 0 0
POE 52/65 48/56 28/53 80 90 20 0 0 0
ARA 65/75 57/63 35/56 90 90 40 0 0 0
Tonight...Cloudy with rain and a few thunderstorms likely. Rain heavy at times. Low 56 near midnight with temperatures rising through the night. NE wind 5-10 mph becoming SE 10-15 mph. Chance of rain 80%.
Tuesday...Showers and thunderstorms likely. A few storms could be severe with locally heavy rainfall likely. Rainfall totals 1-3". High 73. Windy. SSE wind 15-20 mph and gusty becoming SSW 15-20 mph and gusty late. Chance of rain 80%.
Tuesday Night...Mostly Cloudy with a 30% chance of showers and thunderstorms in the evening, then clearing and turning cooler. Low 53. SSW wind becoming NNW at 15 mph and gusty.
Wednesday...Sunny and Cooler. Breezy. High near 60. North wind 10 mph.
Wednesday Night...Clear and Cold. Low 34. Calm wind.
Thursday...Sunny and Cool. High 55. NE wind 5-10 mph.
Drew's 7 Day Outlook for Lake Charles & Vicinity
Tuesday
12-8-09
Low: 56
High: 73
Rain: 80%
Wind: SSE/SSW 15-20
Wednesday
12-9-09
Low: 53
High: 60
Rain: 0%
Wind: N 10
Thursday
12-10-09
Low: 35
High: 55
Rain: 0%
Wind: NE 5-10
Friday
12-11-09
Low: 41
High: 57
Rain: 60%
Wind: NE 10-15
Saturday
12-12-09
Low: 45
High: 58
Rain: 20%
Wind: NE 10-15
Sunday
12-13-09
Low: 38
High: 62
Rain: 0%
Wind: N 10
Monday
12-14-09
Low: 44
High: 63
Rain: 40%
Wind: E 10-15
...Marine Forecast...
Tuesday...South winds 15 to 20 knots. Seas 3 to 5 feet. A chance of showers and thunderstorms.
Tuesday Night...Southwest winds 15 to 20 knots becoming west 10 to 15 knots after midnight. Seas 4 to 6 feet subsiding to 3 to 5 feet after midnight. A slight chance of showers and thunderstorms in the evening.
Wednesday...North winds 15 to 20 knots. Seas 2 to 4 feet subsiding to 2 to 3 feet in the afternoon.
Wednesday Night...Northeast winds 15 to 20 knots. Seas 2 to 3 feet.
Thursday...Northeast winds 15 to 25 knots. Seas 3 to 5 feet. A chance of rain.
...Tide Data...
Tuesday Tides @ Calcasieu Pass
Low: 2:54a.m. 1:36p.m.
High: 5:52a.m. 8:07p.m.
...Toledo Bend...
171.01'
...Lake Charles Climate Summary...
Monday, December 7, 2009
Low: 54
Normal Low: 45
Record Low: 21-1950
High: 61
Normal High: 65
Record High: 83-1912
Precipitation
Today: 0.53"
Month to Date: 2.52"
Normal Month to Date: 1.03"
Year to Date: 67.06"
Normal Year to Date: 53.62"
Record: 2.77"
Sunrise Tuesday: 6:57a.m.
Sunset Tuesday: 5:13p.m.
Tuesday Hunting Times: 6:27a.m.-5:43p.m.
...Lunar Table...
Last Quarter- Wednesday December 9
New Moon- Wednesday December 16
First Quarter- Thursday December 24 (Christmas Eve)
Full Moon- Thursday December 31 (New Year's Eve)
Good night and God bless!
-DM-
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