SW Louisiana Forecast Discussion... The cold front arrived right on schedule this morning with widespread shower and thunderstorm activity. This produced more heavy rain across the area. Some flooding problems were experienced, but overall the worst of the flooding missed the forecast area. However, our friends to the East towards New Orleans have been absolutely deluged with nearly 10" of rain since Monday. New Orleans has established an all-time record for rainfall for the month of December, and is nearing it's all time record for rainiest month. More on this in a little bit, but now back to what's going on closer to home. The rain and storms persisted through the morning hours, there was even some reports of small hail near Sulphur and Vinton. Average rainfall totals were 1-3" across the forecast area with higher amounts across coastal areas, and lesser amounts for the northern portion of the forecast area. Temperatures fell throughout the day, and continue to do so at this hour as CAA was established being the advancing cold front. Temperatures fell from the mid to upper 60s at midnight into the 40s to near 50 at this hour. CAA continues tonight with widespread cloudiness across the forecast area. The good news is, it will be a quiet night across the entire area with no rain expected as drier air filters into the region in response to a strong high to our North. Temperatures will continue to decline through sunrise Wednesday, and you can expect a chilly morning with readings ranging from the mid 30s to mid 40s across the forecast area. Winds will continue to be gusty as well in response to the post-frontal pressure differences that typically arise in CAA regimes.
Wednesday will be dry, but unfortunately we'll have to wait to see much sunshine as the clouds will hold firm. The cold front will pull up stationary over the Gulf, and at the same time another upper level impulse embedded in the Subtropical Jet Stream, which seems to be a permanent resident these days, rotates towards the forecast area. This will keep mid and high-level clouds in place in advance of the system, but some sunshine may filter through at times. Drier air in place at the surface may help scour out the low cloud deck across the forecast area Wednesday morning. Clouds will be thinner the further North you go in the forecast area, and if you are seeking sunshine the Northern half of the state should see a beautiful day on Wednesday. It should be a rain-free day, but it will remain on the cool side. CAA will continue through the day, and with the clouds preventing maximum potential daytime heating temperatures will struggle to reach 50. High temperatures will range from the upper 40s to lower 50s. By late Wednesday, the advancing short wave over West Texas will help energize the stalled front in the Gulf. The Subtropical Jet Stream and this piece of energy will work in tandem to initiate another Western Gulf low. Clouds will lower and thicken overnight. It will remain on the chilly side as we remain influenced by the fringe effects of the Arctic high. Lows will be around 40 with NE winds 10-15 mph. A few light showers may develop across the Southern half of the forecast area after midnight as the Gulf low moves up the coast.
Rain chances return in earnest on Thursday, unfortunately. However, the silver lining, if there is one, is that the heavy rains with this event should remain offshore. The low should track a bit further South than its predecessors. The expected track farther to the South will produce a likely chance of light rain/drizzle for much of the day on Thursday. Rainfall totals should be on the light side with average amounts of 1/4 to 1/2". This should not lead to any additional flooding problems. There's a chance this could change if the low tracks further North in closer proximity to the coast. The progression of this low will be monitored for any necessary revisions to the forecast. The expected track of the low will also result in smaller rain chances the further North you go. Locations such as Fort Polk and Alexandria may see very little in the way of the pesky stratiform precipitation mentioned above. Rain chances will be tempered downward the further away from the coast you go, but it will be likely for the Southern half of the forecast area. The chance for light rain and drizzle will persist into Thursday night as the low slowly trudges to the ENE across the coastal waters thus keeping the overrunning in place. The isentropic upglide that will be responsible for the drizzly, dreary, and drab conditions Thursday will keep temperatures on the cold side as well. Maximum will be closer to the normal low for this time of year as opposed to the normal high. Expect highs in the mid to upper 40s, some 10-15 degrees below normal. Thus, here's another illustration of a typical El Nino winter in South Louisiana. The first half of the month has predominantly been below normal for temperatures, and has definitely been above normal for precipitation. The overrunning will subside overnight with light rain and drizzle becoming patchy in nature after midnight. Temperatures won't fall much with the continued cloud cover and intermittent rain. I expect a low for Thursday night/Friday morning to be in the upper 30s to around 40. The low pressure over the Gulf will make for very rough conditions in the coastal waters, and large waves and high seas are expected once again as winds gusts into tropical storm range. Over land, the wind will be a little bit less thanks to the friction of the Earth, but it will still be quite windy with winds over 20 mph at times.
Finally, we get to see some sunshine on Friday. This will be a great way to close out the last full work week of the year, and the last school day before Christmas break. The day may start with some lingering clouds as the low continues to exit stage right, but high pressure will be taking over ushering in much drier air as a NWly flow aloft is established and strengthens in its wake. A cool start will translate into a cool afternoon with highs remaining shy of 60. Friday should begin a stretch of a prolonged dry period with a series of dry fronts and highs to influence the region into early next week within the established NW flow. The passage of this low will essentially open the door to the Arctic in a big way. I will elaborate more on this in the coming days. The first deposit of Arctic air should arrive over the weekend as the next cold front moves through the area on Saturday. After another night of seasonably cold weather for Friday night, this front will lead to freezing temperatures by Sunday morning. Saturday should be a nice day despite a cold front. The front will push through with limited moisture to work with, and no rain chance is anticipated. A few clouds will be possible ahead of the front, but overall a cloud free forecast is expected. Highs on Saturday ahead of the front will approach 55, but temperatures will quickly fall off behind the boundary Saturday evening. It looks quite cold outside as we're sitting down inside to watch the Saints-Cowboys game. By Sunday morning, a freeze expected everywhere with the possible exception of the immediate coast, but even they could get in on the action. Lows should range from the mid 20s in Central Louisiana to around 30 along I-10 to the lower 30s at the coast.
Clear and cold weather prevails for Sunday and Monday with a freeze each morning and afternoon highs in the low to mid 50s. This air mass will be modified Arctic air, but I still feel the models are underestimating the strength of the cold air, and I may lower the max temperatures over the next or day as the Arctic air begins its Southward transport, and see how things evolve. Monday morning temperatures should be similar to that of Sunday, while the afternoon readings for the start of Christmas week should be in the low to mid 50s. A brief surface return flow is established Monday afternoon as the Arctic high slides Eastward, and another even stronger surge of Arctic air begins its Southward tug. This front should bring some clouds, but no rain for the Tuesday period. It will still be a cold morning with lows above freezing, however. I expect mid to upper 30s ought to suffice for day 7. Afternoon highs will be a tad cooler than that of Monday due to the current projected timing of the front. I expect mid 50s before temperatures begin falling late in the day. The overall pattern should remain unseasonably cold through Christmas, and I don't see anymore 70 degree days for awhile. Some models hint at a serious Arctic outbreak across the Eastern 2/3 of the nation by the middle of next week lasting through Christmas, so we'll just have to see how all of this unfolds. You certainly can't ignore the fact that current readings in portions of Central Canada are as cold as -40. I really believe models are too warm on current guidance for next week for this reason. It's still a ways off, so I will defer a further evaluation until later forecasts. Just know that the signals are there for a very cold Christmas. The wet pattern that has persisted for the first half of this month is likely to persist as long as the Subtropical Jet Stream remains a player. Stay tuned, I'm sure there will not be too many dull moments in the weather world to close out the year.
What a lot of rain...December 14-15, 2009: New Orleans, LA...The city of New Orleans has set some rainfall records this week with the vigorous storm system that has been impacting Louisiana since Monday. As of 11p.m. tonight, New Orleans received a whopping 5.70" of rain today, and 3.28" of rain on Monday. This is a 2 day total of almost 9" at 8.98" at the Louis Armstrong International Airport. This gives Louisiana's largest city a monthly total for December of 22.48". This is the all-time wettest December on record at New Orleans, and the wettest month ever since records for New Orleans have been kept at the current location in Kenner. This dates back to 1947. The previous record for all-time wettest month at New Orleans International was May 1995 with 21.18". Prior to 1947, records for New Orleans were kept elsewhere, and these records indicate that the all-time wettest month for the New Orleans Metro area occurred in October of 1937 when more than 2' of rain fell in the city. The final tally that wet October was 25.11". It is likely that Nee Orleans will establish a record for all-time wettest month ever with 1/2 month still to go. For the year, the official reporting site is approaching 76" for 2009, and it is certainly feasible that in excess of 80" of rain for the year will occur. Of note, it has been an above average year for rainfall all across Louisiana. Significant flooding has occurr across much of South Louisiana in the last few days.
Preliminary Numbers & Zone Forecast:
LCH 40/53 41/47 38/56 0 0 30 70 40 0
LFT 39/52 40/48 40/55 0 0 30 70 40 0
BPT 42/54 41/47 39/56 0 0 40 70 30 0
AEX 35/50 36/44 34/51 0 0 20 40 20 0
POE 36/51 37/45 35/52 0 0 20 40 20 0
ARA 41/54 41/48 39/55 0 0 30 80 40 0
Tonight...Mostly Cloudy, Windy, and Colder. Low 40. NNE wind 15-20 mph and gusty. Wind chill 25-35 by morning.
Wednesday...Mostly Cloudy, Cool and Breezy. High 53. NE wind 10-15 mph.
Wednesday Night...Cloudy with a 30% chance of light rain or drizzle. Low 41. NE wind 15-20 mph and gusty.
Thursday...Cloudy and Cold with light rain and drizzle likely. High 47. NNE wind 15-20 mph and gusty. Wind chill in the 30s.
Thursday Night...Cloudy with a 40% chance of light rain and drizzle ending overnight. Low 38. North wind 10-15 mph. Wind chills 25-30.
Friday...Becoming Mostly Sunny. High 56. North wind 10 mph.
Drew's 7 Day Outlook for Lake Charles & Vicinity
Wednesday
12-16-09
Low: 40
High: 53
Rain: 10%
Wind: NE 10-15
Thursday
12-17-09
Low: 41
High: 47
Rain: 70%
Wind: NE 15-20
W.C.: 30s
Friday
12-18-09
Low: 38
High: 56
Rain: 0%
Wind: N 10
Saturday
12-19-09
Low: 37
High: 54
Rain: 0%
Wind: NW 10-15
Sunday
12-20-09
Low: 30
High: 52
Rain: 0%
Wind: NW 10-15
W.C.: 20-25
Monday
12-21-09
Winter Solstice
Low: 32
High: 56
Rain: 0%
Wind: NE 5-10
Tuesday
12-22-09
Low: 34
High: 47
Rain: 0%
Wind: NNW 20-25
W.C.: 20s
...Marine Forecast...
*Small Craft Advisory through Noon Wednesday.*
Tonight...Northeast winds 15 to 25 knots. Seas 3 to 5 feet.
Wednesday...Northeast winds 15 to 20 knots. Seas 3 to 5 feet subsiding to 3 to 4 feet in the afternoon. A slight chance of rain.
Wednesday Night...Northeast winds 15 to 20 knots. Seas 3 to 4 feet. A chance of rain.
Thursday...Northeast winds 15 to 20 knots becoming 15 to 25 knots in the afternoon. Seas 3 to 4 feet building to 3 to 5 feet in the afternoon. A chance of rain. Isolated thunderstorms in the afternoon.
Thursday Night...North winds 15 to 25 knots becoming 15 to 20 knots after midnight. Seas 3 to 5 feet subsiding to 2 to 4 feet after midnight. A chance of rain in the evening.
Friday...Northwest winds 10 to 15 knots. Seas 2 to 3 feet.
...Tide Data...
Wednesday Tides @ Calcasieu Pass
Low: 8:16a.m.
High: 4:10p.m.
...Toledo Bend...
170.55'
...Lake Charles Climate Summary...
Tuesday, December 15, 2009
Low: 46
Normal Low: 43
Record Low: 24-1914
High: 65
Normal High: 63
Record High: 81-1995
Rainfall
Today: 0.98"
Month to Date: 6.75"
Normal Month to Date: 2.15"
Year to Date: 71.29"
Normal Year to Date: 54.74"
Record: 4.38"-1986
Sunrise Wednesday: 7:02a.m.
Sunset Wednesday: 5:15p.m.
Wednesday Hunting Times: 6:32a.m.-5:45p.m.
...Lunar Table...
New Moon- Wednesday December 16
Last Quarter- Thursday December 24
Full Moon- Thursday December 31
First Quarter- Thursday January 7
Good night and God bless!
-DM-
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