*Coldest Weather in 16 Years on Tap for the End of the Week Through the Weekend.*
*The Impinging Record Cold Will Keep the Blog in Short Form through the Weekend.*
SW Louisiana Forecast Discussion...It was a cold day indeed on the first Monday on 2010. Another Arctic front moved through in the early morning hours, and this helped to strengthen CAA across the area. Low clouds hung tough across the area in the wake of the front, and in response to an upper level disturbance moving from NW to SE across Arkansas and North Louisiana. This disturbance found enough moisture to work with to produce light wintry precipitation across these areas. Several inches of snow was reported across Arkansas, while a light dusting occurred in North Louisiana from Shreveport to Monroe. Some light freezing rain occurred in these areas as well, but alas our area was precip free today. The clouds were a nemesis, however, as they helped to keep temperatures in check with very little warm up during the day as the CAA continued. Temperatures were in the mid 30s to lower 40s throughout the day. The low clouds are eroding tonight as strong Arctic high pressure builds in, and this will set the stage for a hard freeze. This will by far be the coldest night of the season so far. A Hard Freeze Warning is in effect not only locally, but for a large portion of the Gulf Coast. Freezing conditions are expected down into citrus country in Florida. The clouds have cleared for much of the area as the high pressure builds in, and the rest of the area will follow suit after midnight. Clouds remain in place at present for locations such as Lafayette and Alexandria. Temperatures will range from the lower 20s in the usual colder locations which are clear at this time, to the upper 20s in the areas which clear late. Even the coast will not escape freezing temperatures this go around with lows right near 30 at sunrise. Winds will be a bit of an issue concerning wind chills. Winds out of the North near 10 mph will occur creating wind chills around 20 in the morning.
Tuesday will be a deceptively nice day, but it will remain cold. The Arctic high pressure will be in complete control. Expect highs to reach the mid 40s after the hard freeze. The sun will try to warm us up, but with the cold air mass in place, it will have a hard time getting much above 45. Another cold night is in store with yet another hard freeze for Tuesday night/Wednesday morning as the Arctic high drifts right over Louisiana by late Tuesday. The clear skies will remain clear and winds will be near calm to help produce even better radiational cooling conditions on Tuesday night. Temperatures will be very similar to tonight, or perhaps a degree or two colder in some locations since there won't be any eroding cloud cover. Wind chills won't be a factor heading into Wednesday morning since winds will be near calm. Cold and dry weather continues through much of the day Wednesday as the Arctic high slowly nudges Eastward. A modest warm up will begin after the Wednesday morning freeze as a return flow off the Gulf is established around the back side of the high, and in advance of a developing surface low out ahead of the main blast of Arctic air. Look for Wednesday maximums to be around 50. Clouds will begin to increase late in the day Wednesday as moisture increases ahead of what's to come...
The big changes begin to occur Wednesday night. Rain chances return to the forecast, and a modest warm up continues. A large polar vortex over Hudson Bay, and a low pressure off the New England Coast will help drive extremely cold weather down towards the Gulf Coast from Southern Canada. Temperatures are around -40 in the source region tonight. The Jet Stream will intensify, and a very deep trough will form to set up this cold outbreak. The advertised warm up will occur out ahead of this as a Southerly flow will be established only briefly. A surface low will advance NE over Texas, and energy from the Subtropical Jet Stream will add to rain chances. Rain will likely be in the likely category by Wednesday night. Lows will be above freezing for all areas, but won't exactly be warm by any stretch. The precipitation should be all liquid on Wednesday night with temperatures in the mid to upper 30s. Snow seems likely for North Louisiana with a chance of some sleet as well depending on how much of a warm up occurs. The Arctic front will not waste anytime moving through the forecast area. I believe the timing of the front still looks to be around sunrise for Lake Charles & Vicinity, and before dawn for Northern areas, and by 9a.m. for Acadiana. The front will keep moving as the Jet Stream intensifies. Just to give you an idea, this cold front will push all the way towards Cancun. Much colder air will be ushered in behind this boundary as CAA intensifies in earnest. The front will put an end to the warm up ongoing, and any 'mild' weather for awhile. Rain will continue for Thursday morning, and it is at this time that there is still much uncertainty. Some indications are that the rain will hang around long enough, for a brief window of opportunity to see some frozen precipitation. As I mentioned last night, it could be a classic case of the precip ending before the coldest weather moves in. However, with added energy from El Nino and the Subtropical Jet Stream some overrunning is expected behind the front, resulting in a continuation of precip as the colder air punches in during the day. If any sleet or snow were to occur, accumulations seem unlikely at least in South Louisiana. A significant snow accumulation is possible for the Northern half of the state, but this is a forecast that will be fine tuned as we head towards mid-week. At this time, I will mention rain changing to sleet and snow during the day Thursday before all precip ends in the afternoon as the Arctic high builds in. Thursday's temperatures will be confused as I like to say. Meaning that, the warmest time of the day will come early, and the coldest part of the day will come late. I believe that model guidance is too warm on Thursday, therefore, I am undercutting these values. I will forecast lows in the upper 30s and a high only reaching the low 40s before temperatures fall to below freezing by late afternoon. As the air mass infiltrates the region, it will be very windy as well. Skies will clear late Thursday as a 1052 mb high slides in. This will begin a prolonged period of below freezing temperatures. The cold blast will rival a February 1996 air mass. Air masses like this come down into the U.S. every winter, but generally we don't get this cold along the Gulf Coast because of air mass modification while its en route. This is mostly due to snow pack. The less of a snow pack there is, the more the air will modify by the time it reaches the Gulf Coast. In contrast, the more snow pack there is, the less the air will modify by the time it reaches the Gulf Coast. This is the case this time as there is a snow pack down into Central Arkansas at present, and it will likely extend a bit further South before the mother load gets here Thursday.
By Friday morning it will be quite frigid and bitter across the area. Clear skies may be present, but the wind and extremely cold temperatures will produce dangerous wind chills. NNW winds 20-25 mph at times will produce wind chills in the single digits Friday morning while actual temperatures will be in the 17-22 range. One change that is noted from yesterday's forecast package, is the possibility of an upper level impulse passing, and associated energy from the active Subtropical Jet Stream. This will likely at least induce cloud formation across the area, but there could be enough moisture for some snow flurries or light snow on Friday into Friday night. However, at this time accumulations seem very unlikely as the air mass will be very dry, and moisture will be very limited. Until I see more model consistency with this idea, I will not mention more than the previously mentioned snow flurries or light snow from around 18Z (Noon CST) Friday and 6Z Saturday (Morning CST). The pattern favors additional short waves to ride down the base of the trough once the cold air moves in Thursday. The big question will be moisture availability. There's no question what type of precip would occur. Stay tuned! While the question remains whether or not there will be any precip with this deep Arctic air mass, there is no question that it's going to be very cold. Friday morning lows will range from the mid 10s north to lower 20s, while afternoon highs fail to reach freezing in most locations. Wind chills will be brutal throughout the day as well making matters worse. Expect the apparent temperature to range from near 0 to 10 degrees. Temperatures will be hard pressed to reach freezing even if the sun is out, so if it's cloudy you can expect it to be even colder.
The best opportunity for any snow beyond Thursday will come overnight Friday into early Saturday as the weak impulse moves from W to E along the Gulf Coast. What little moisture that is available will be squeezed out with periods of snow flurries or light snow showers at this time. Again, no accumulation is expected with the air being so dry. However, even colder temperatures are expected Friday night as re-enforcing surges of Arctic air continue to come through the area. 10s are expected area wide Friday night, and I am undercutting guidance which is already forecasting lows near 20 to the upper 10s for Saturday. The position of the Arctic high and Polar Vortex will favor a record cold morning. Temperatures will range from around 13 towards Alexandria to 16 at Lake Charles and 20 right along the coast. The weak impulse will quickly move East, and clear skies will return for Saturday during the day, but temperatures will only recover to the mid to upper 20s as CAA continues. It now appears that the extremely cold temperatures will continue through Sunday with another record low expected on Sunday morning. Conceivably temperatures could even be a degree or two colder Sunday morning as the Arctic high will nestle in right over Louisiana. I am once again undercutting guidance at this point. Temperatures could be as cold as 10 for Alexandria, and will likely be in the 10s even at the coast. This is a situation that where no one will be unscathed a hard freeze. I will forecast mid 10s for Lake Charles for the Saturday night/Sunday morning period. the Arctic high will only slowly move East by Sunday afternoon. Some slight modification is expected Sunday, but highs will still be in the 30s, and if the current trends continue we may not get to freezing for the entire area on Sunday either. This would be the longest period below freezing since 1996. It doesn't appear that we'll mirror temperatures experienced in 1989, but this will definitely be a historical cold spell.
Air mass modification finally commences Monday as the major Arctic high slides to our East. Morning lows on Monday will once again be well below normal, but not quite at record levels as the modest warming trend keeps temperatures in the low to mid 20s to start the day. Skies will be sunny, and finally by late morning we'll warm above freezing. We'll have the potential to be below freezing 72-84 straight hours, truly an amazing feat in South Louisiana. No one is going to be saying that we didn't have a winter this year! There are no signs of any other opportunities for precipitation from Saturday through Monday. Afternoon highs on Monday should reach the upper 30s to lower 40s. Beyond the forecast period, a warm up is inevitable, but it certainly will nly get warm in a 'relative' sense. I expect a prolonged period of below normal temperatures to continue through the middle of January. Another freeze is possible on day 8, before we'll finally see some lows above freezing again. Highs will continue to recover as well possibly approaching 60 sometime next week. A significant rain maker is in the offing sometime next week, as the active El Nino pattern re-establishes itself. The cold weather won't be over with after this major outbreak, but I doubt we'd see anything this cold again this winter. Stay tuned for all the latest on this severe cold outbreak!
Here are some cold weather safety tips:
Check your car for anti-freeze.
Protect your plants.
Protect your pets.
Protect your pipes. You should wrap all exposed pipes especially if you live in an elevated home. It is often a good idea to drip the faucet in your home as well.
Protect yourself. You should dress in layers, and make sure you protect yourself from frostbite and other cold weather problems. The elderly are essentially prone to problems in the cold weather, so check up on them.Wear a hat and gloves. Most of your body heat escapes through your head.
Use extreme caution when using space heaters. These are a major fire hazard.
Do not use the stove or oven as a heating source for your home.
Preliminary Numbers & Zone Forecast:
LCH 25/46 26/50 38/44 0 0 0 0 70 60
LFT 28/45 25/49 37/43 0 0 0 0 60 70
BPT 26/47 27/52 40/45 0 0 0 0 70 60
AEX 23/43 21/45 34/40 0 0 0 0 70 60
POE 23/44 22/46 35/41 0 0 0 0 70 60
ARA 28/45 25/49 40/46 0 0 0 0 60 70
*Hard Freeze Warning in effect until 8a.m. Tuesday.*
Tonight...Clearing and Very Cold with a Hard Freeze. Low 25. North wind 5-10 mph. Wind chill readings near 20 by morning.
Tuesday...Sunny and Cold. High 46. Light North wind.
Tuesday Night...Clear and Continued Very Cold with Another Hard Freeze. Low 26. Light NE wind.
Wednesday...Sunny and a bit Warmer. Increasing Clouds late. High 50. NE wind becoming SE at 10-15 mph.
Wednesday Night...Mostly Cloudy and Not as Cold with rain likely. Low 38. SE wind 10 mph. Chance of rain 70%.
Thursday...Cloudy, Windy, and Turning Very Cold with rain likely early. Rain possibly mixing with sleet and snow before ending shortly after noon. No sleet or snow accumulation. High 44 in the morning, with temperatures falling to near 30 late afternoon. SSW wind 15-20 mph and gusty, becoming NNW at 20-30 mph and gusty before noon. Wind chill readings in the 10s by late afternoon. Chance of precipitation 60%.
Drew's 7 Day Outlook for Lake Charles & Vicinity
Tuesday
1-5-10
Low: 25
High: 46
Precip: 0%
Wind: N 5-10
W.C.: 18-23
Wednesday
1-6-10
Low: 26
High: 50
Precip: 0%...70% Overnight
Wind: SE 10-15
W.C.: 20-35
Thursday
1-7-10
Low: 38
High: 44
Falling to 30
Precip: 60% Mix
Wind: NNW 20-30
W.C. 15-25
Friday
1-8-10
Low: 19
High: 29
Precip: 20% Snow Flurries
Wind: NNW 15-20
W.C.: -5- 15
Saturday
1-9-10
Low: 17
High: 29
Precip: 0%
Wind: N 10-15
W.C.: 10-15
Sunday
1-10-10
Low: 15
High: 34
Precip: 0%
Wind: NE 5-10
W.C.: 10-20
Monday
1-11-10
Low: 21
High: 42
Precip: 0%
Wind: SE 5-10
W.C.: 20-30
...Marine Forecast...
Tonight...North winds 10 to 15 knots. Seas 2 to 3 feet subsiding to 1 to 3 feet after midnight.
Tuesday...North 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 foot.
Wednesday...East winds 10 to 15 knots increasing to 15 to 20 knots in the afternoon. Seas 1 to 2 feet building to 2 to 3 feet in the afternoon.
Wednesday Night...Southeast winds 15 to 20 knots becoming south after midnight. Seas 2 to 4 feet. A slight chance of rain in the evening...then rain likely and isolated thunderstorms after midnight.
Thursday...North winds 20 to 30 knots and gusty. Seas 3 to 5 feet.
Good night and God bless!
-DM-
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