Before I get to the forecast discussion, I just want to remind you that the blog is now back at full capacity. Also, this week marks the 13th anniversary of the worst winter storm in SW Louisiana History...the Ice Storm of 1997! I will post a special blog entry on Wednesday to rehash the event, and discuss the synoptic set up of the event, and all of the meteorology involved in forecasting such an unprecedented event around here. If you have any questions or comments regarding the Ice Storm of 1997 just drop me a line at any time. Now onto the forecast discussion...
SW Louisiana Forecast Discussion...It was another frigid start on this Monday as temperatures ranged from the upper 10s to lower 20s once again for the 3rd consecutive morning, and it was the 4th straight morning of hard freeze conditions. It was a beautiful Monday across the area as the weakening Arctic high continued to dominate the weather. Skies were sunny for a majority part of the day. Some high cirrus clouds rolled in during the afternoon in response to a minor short wave out ahead of a re-enforcing cold front. Moderation occurred this afternoon as temperatures climbed to around 50 or just above in most areas. A very light return flow is in place tonight ahead of the dry re-enforcing front. This front will move through with very little in the way of moisture to work with, and no rain is expected as it pushes through after midnight. Temperatures will once again be below freezing, but as the air mass modification continues it won't be near as cold. Most areas should remain above hard freeze criteria. The immediate coast should escape freezing temperatures all together. Expect the Tuesday morning low to range from the mid 20s to lower 30s. Winds will kick back around to the NW after midnight as the boundary clears the area.
The core of the cold air behind this front will not be near as cold as the current retreating air mass, and we'll only receive a glancing blow from the air mass. Therefore, not much change in temperature is expected, and it will essentially help to level off temperatures for the next couple of days. Benign weather is expected on Tuesday as the re-enforcement high builds in temporarily. Sunny skies are expected, and the air will remain very dry. Temperatures will be similar to that of today, perhaps a degree or two warmer, but lower 50s should suffice. The air mass moving in behind the front will not affect overnight temperatures for Tuesday night much either as the core of the cold air slides to our East. Another freeze is in store for Tuesday night. Temperatures will be a tad colder, but should still stay above hard freeze conditions for much of the area. The exception will be across Central Louisiana where temperatures could be as cold 22 or 23. The rest of the area should be in the 25-30 range. The immediate coast will flirt with the freezing mark, but no matter where you are it won't be near as cold as it has been. If the temperatures drop below freezing for the Tuesday night/Wednesday morning as expected then that will mark 10 straight days with a below freezing minimum at Lake Charles, and as much as 13 straight days for portions of the area. This is a streak that has not been matched in quite some time. In an average year, we don't see 10 freezes over the course of the 3 month winter period, much less in one month.
This overall cold pattern will be changing this week, and this should begin after the morning freeze on Wednesday. It should still be a dry day Wednesday, but clouds will increase during the day as a return flow is established as the re-enforcing high vacates the area. At this same time, our next storm system will be taking shape. There are multiple meteorological components that will come together to produce a very significant storm. The next advancing trough is diving into the Pacific Northwest tonight. The primary weather pattern across the country will shift to a 'split flow'. This means there will be the presence of 2 Jet Streams across the country...the STJ (Subtropical Jet) and the main Polar Jet. The Polar Jet will shift back towards the North, after being down into the Gulf this weekend, and the STJ will become active and stream over our area once again. The digging trough over the Pacific NW split, sending a part of it to the South towards our area. The advancement of this system will engender cyclogenesis over the Western Gulf off the lower Texas coast. This is same pattern we've endured plenty of times already this season. (El Nino). The Arctic air has cut us a reprieve from this pattern so far this year. This comes to an end by Thursday. For the last dry day on Wednesday, temperatures will once again remain below normal with maximum similar to Tuesday in the mid 50s. The WAA pattern ahead of the developing storm system takes a firm grip on the forecast area Wednesday night with lows above freezing for the entire forecast area, though the Northern portions of the area will be close. Mid to upper 30s seem feasible for overnight minimums heading into Thursday morning.
I couldn't rule out a shower or two Wednesday night after midnight with the advancement of the trough and formation of the low resulting in increasing isentropic lift across the area. The moderating trend will continue as WAA strengthens. The low pressure will only move slowly up the coast. Rain chances will increase throughout the day Thursday. Rainfall will be scattered at first as some streamer showers will be possible especially closest to the coast where isentropic lift will be greatest. Rain will become likely Thursday afternoon as the surface low, and short waves embedded in the STJ advance NE across the forecast area. The set up favors widespread stratiform rainfall at this time. Temperatures will continue to moderate, and highs should be just shy of 60. The stratiform rains continue on Thursday night as the low slides NE up the coast, and the rain overspreads the region. Overnight lows Thursday will be in low to mid 40s...seasonable. This will break the streak the mornings with below freezing temperatures.
The worst conditions of the week come on Friday and Friday night it appears. The surface low will make its approach to the coast, and move inland over the forecast area. The exact track and timing of said occurrence is still uncertain, but it should be Friday afternoon, and track very close to Lake Charles. As I discussed last night, this system is forecast to become vertically stacked. This may result in a slower forward speed of the surface low, therefore, the rain may last a longer duration. The specifics of this will be hammered out tooth and nail later this week, right now though, it is essential that you understand that all the makings of a prolonged rain event are in place. The low tracks into the forecast area, and brings with it the possibility of cumuliform rain. There will be plenty of forcing and upper level dynamics for this system to work with, but the main inhibiting factor will be instability. The low and associated trough are the present forcing mechanisms. Rain could become heavy at times Friday as the deep moisture associated with the low overspreads the forecast. There will be the potential for several inches of rain Friday. We've been in a much drier pattern to start the year with all the cold air in place. Rainfall totals so far for the new year are less than an inch. However, the soil content is still very wet, and the ground is very hard now with all the cold weather. We will exceed an inch of rain very easily for this event, how much we ultimately wind up remains to be seen. The potential for flooding rains will exist as the low works into the region Friday afternoon. The low will be strengthening as it moves up the coast as well. This will tighten the pressure gradient across the forecast area, and over the coastal waters. The end result is strong, gusty winds on Friday. I don't anticipate severe weather at this time, however, areas to the right of the low could experience some sort of severe weather threat depending on how much WAA entrains into the system, and how much instability is generated. Rain chances will end up maxing out for the Friday-Friday night period as the entire mess conglomerates over SW Louisiana/SE Texas. It won't exactly be warm while its raining, but Friday's temperatures should be in the mid to upper 50s...again, this is about seasonable for mid-January.
The rain chances will stick with us through Saturday. Heavy rain will once again be possible for Friday night with maximum isentropic lift in place as the low pulls NE into Louisiana. The Friday night period should also see maximum rain chances, with some reprieve possible late. Weak CAA will begin as the low pulls away Friday night, and overnight minimums should be in the upper 30s to lower 40s. All precipitation should stay in the liquid form. The wind will once again be an issue as the low deepens further, and high pressure coming down the spine of the Rockies tries to build in. Winds will continue to be out of the NNW around 20 mph because of the pressure differences. Winds to hurricane force are possible in the offshore waters. Rain is likely for Saturday too, however, how much rain and when it quits remains to be seen. There are some models that indicate rain ends sometime Saturday while others believe it will continue into Sunday. For purposes of this forecast, I will blend these ideas. Rain chances certainly continue into Saturday. The synoptic scale set up features this low deepening quite rapidly, especially since it will be El Nino and STJ enhanced. This is going to be a very dynamic system, and is sure to wreak havoc across the area. Conditions only slowly improve Saturday as the low pulls away, and the overrunning slowly relaxes. Saturday will be quite raw with the gusty winds, rain, and falling temperatures most likely. Highs should be in the mid 40s, but wind chills will be in the 30s. Nothing is cold compared to what it has been, although it will feel very cold with the cold and rain in the area. It's still a bit premature as the system hasn't really gotten its act together yet, but here is a QPF (Qualitative Precipitation Forecast). QPF is basically the estimated expected rainfall for a particular area.
Saturday night is when a noticeable improvement occurs as the low departs, and CAA is established once again. I don't think we'll shed the clouds just yet, and certainly have to mention a chance of rain in this pattern as there will be plenty of residual moisture in place. Overnight lows will hit the 30s, and northern areas may flirt with the freezing mark. However, the rain should stay all liquid, and it will end before it gets cold enough to support anything else. There could be a big snowstorm from Dallas to Atlanta during this time, but that remains to be seen as well. While there are still many uncertainties due to timing and amounts, and to a lesser extent, the degree of the system, it is certain that we'll have a prolonged rain event. Improvement continues for Sunday as the system continues to pull away, and Pacific High pressure builds in. The air mass behind this system is no where near as cold as its predecessor. Therefore, only seasonably cold weather is expected for Saturday night and Sunday. The Saturday maxes in the 40s will be held down by the rain and continued CAA. Max temperatures should eclipse the 50 degree mark Sunday as some sun peaks through by afternoon. Clouds will be slow to erode on Sunday, especially if there's plenty of wrap around moisture available generating a low-level temperature inversion and associated stratus deck. The high pressure builds in full throttle for the end of the forecast period Sunday night-Monday, and as a result clear skies and seasonably cool temperatures are expected with lows in the 30s and highs in the 50s. Some people are likely off of work/school on Monday for a nice 3 day weekend for Martin Luther King, Jr. Day. It looks like a nice day with plenty of sunshine and low humidity. Highs should approach 60. Looking long range, a warming rend is forecast to continue beyond the forecast period, and temperatures could reach above normal levels next week. That being said, winter isn't over, and I would expect more shots of Arctic air before the winter is over.
This Date in Weather History...January 11: Big-time Arctic Outbreak: The air mass that flooded the U.S. back in January of 1982 was even colder than the one that has us shivering at present. This Arctic outbreak peaked on this date in 1982. Several record lows were set in the Southern U.S., including 15 right here in Lake Charles. Single digits were experienced in the Northern half of the state. Alexandria bottomed out at 9 degrees, while Shreveport hit an amazing 5 degrees. Other notable record lows for the date of January 11, 1982 include -5 F at Atlanta, GA and -2 F at Birmingham, AL. Single digits were even recorded in parts of Florida with Pensacola reaching 8 F. In all, a total of 34 record lows were established across the country for the date.
Preliminary Numbers & Zone Forecast:
LCH 28/53 27/55 36/58 0 0 0 0 30 60
LFT 27/52 26/56 35/57 0 0 0 0 30 50
BPT 29/55 28/56 38/58 0 0 0 0 40 70
AEX 24/51 23/54 30/55 0 0 0 0 30 50
POE 25/52 24/55 31/55 0 0 0 0 30 50
ARA 27/53 26/57 37/58 0 0 0 0 30 50
Tonight...Clear and Not Quite as Cold. Light Freeze. Low 28. Light SW wind, becoming NNW at 10 mph after midnight.
Tuesday...Sunny. High 53. North wind 10 mph.
Tuesday Night...Clear and Cold with Another Freeze. Low 27. Light NE wind.
Wednesday...Increasing Cloudiness. High 55. SE wind 10-15 mph.
Wednesday Night...Cloudy and Warmer with a 30% chance of rain after midnight. Low 36. SE wind 10 mph.
Thursday...Cloudy with rain and a few thunderstorms developing. Rain becoming likely in the afternoon. High 58. SE wind 10-15 mph. Chance of rain 60%.
Drew's 7 Day Outlook for Lake Charles & Vicinity
Tuesday
1-12-10
Low: 28
High: 53
Precip: 0%
Wind: N 10
W.C.: 25-35
Wednesday
1-13-10
Low: 27
High: 55
Precip: 0%
Wind: SE 10-15
W.C.: 25-35
Thursday
1-14-10
Low: 36
High: 58
Precip: 70%
Wind: SE 10-15
W.C: 30-40
Friday
1-15-10
Low: 42
High: 55
Precip: 100%
Wind: SE/NNE 15-25
Saturday
1-16-10
Low: 38
High: 44
Precip: 90%
Wind: NNE 15-20
W.C.: 25-35
Sunday
1-17-10
Low: 35
High: 53
Precip: 20%
Wind: NNW 10-15
W.C.: 25-35
Monday
1-18-10
Martin Luther King, Jr. Day
Low: 32
High: 57
Precip: 0%
Wind: N 10
W.C.: 25-40
...Marine Forecast...
Tuesday...Northeast winds 5 to 10 knots. Seas 1 to 2 feet subsiding to 1 foot in the afternoon.
Tuesday Night...Northeast winds 5 to 10 knots. Seas 1 to 2 feet.
Wednesday...East winds 5 to 10 knots becoming southeast in the afternoon. Seas 1 to 2 feet.
Wednesday Night...Southeast winds 5 to 10 knots increasing to 10 to 15 knots after midnight. Seas 1 to 2 feet. A slight chance of rain after midnight.
Thursday...East winds 20 to 30 knots. Seas 2 to 4 feet. A chance of rain.
...Tide Data...
Tuesday Tides @ Calcasieu Pass
Low: 6:55a.m.
High: 3:01p.m.
...Toledo Bend Pool Level...
170.33'
...Lake Charles Climate Summary...
Monday, January 11, 2010
Low: 21
Normal Low: 41
Record Low: 15-1982
High: 52
Normal High: 60
Record High: 79-1980
Precipitation
Today: 0.00"
Month to Date: 0.43"
Normal Month to Date: 1.99"
Year to Date: 0.43"
Normal Year to Date: 1.99"
Record: 1.65"-1946
Sunrise Tuesday: 7:10a.m.
Sunset Tuesday: 5:33p.m.
Tuesday Hunting Times: 6:40a.m.-6:03p.m.
...Lunar Table...
New Moon- Friday January 15
First Quarter- Saturday January 23
Full Moon- Saturday January 30
Last Quarter- Friday February 5
Good night and God bless!
-DM-
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