***Because of an active weather situation for later this week, the blog is back in severe weather mode.***
Before I get to the forecast discussion, here is a brief aside. The recent cold wave was historical in some aspects. It certainly wasn't anywhere near the all-time coldest temperatures ever experienced in SW Louisiana, but there were a few daily record lows established during that time. However, you can take it deeper than that...it was a prolonged stretch of unseasonably cold weather across the area. Just how cold was it? How does it match up with the all-time records as far as all-time prolonged cold snaps? I inquired about this very subject last week with the National Weather Service, and here is what was found. I specifically asked what was the longest stretch of days in recorded history at Lake Charles where the minimum temperature was 35 or lower. I should note that the normal low for the first half of January is around 40.
*The following data is courtesy of the National Weather Service Office in Lake Charles.*
The recent stretch of cold weather, January 2-13 was the longest stretch of daily minimums of 35 degrees or lower in recorded history at Lake Charles. The previous longest stretch was 10 days set in January 8-17, 1982.
Here's a closer look at the low temperature at Lake Charles for each day from January 1-13, 2010.
*This data is the official record for LCH for the specific dates above.
January 1- 36
January 2- 34
January 3- 34
January 4- 30
January 5- 25
January 6- 28
January 7- 30
January 8- 26
January 9- 21
January 10- 20
January 11- 21
January 12- 32
January 13- 30
The average temperature during the first 13 days of January was 28.2. This is 12-14 degrees below normal for early January. Thanks to Donald Jones of the National Weather Service, Lake Charles for supplying this information.
SW Louisiana Forecast Discussion...The El Nino storm parade has taken over full throttle once again. The signs of the next storm system are already visible with clouds on the increase after a beautiful MLK Day. Fog was an issue this morning, with some areas experiencing dense fog until about an hour or so after sunrise, but once it burned off it was a pleasant day with sunny skies and temperatures warming well into the 60s after a chilly start in the mid 30s to around 40. This benign weather was in the wake of the big Gulf low that brought us strong winds and rain over the weekend. The Pacific high pressure that has controlled the forecast since Sunday has traveled Eastward this evening, and as a result a return flow of low-level moisture has commenced across the forecast area. This will by far be the deepest return flow we've experienced so far in 2010, and the mild temperatures will only get milder over the next couple of days as the Jet Stream remains far to our North, and the Subtropical Jet Stream is the dominant weather feature around these parts. The next storm system to affect the area is walloping the West Coast tonight with heavy rain and flash flooding. This Southern Stream system is what will be on tap for us Wednesday...more on that in a minute!!!
For tonight, quiet weather is in store as the low-level return flow continues. Deeper Gulf moisture will move inland, and WAA will dominate. The only issue for tonight will once again be fog. However, it may pose more of a problem tonight than it did last night because it will be an advection fog as opposed to a radiation fog. Fog will become widespread across the area after midnight, and it will very dense in some areas, possibly reducing visibilities to near 0 at times towards morning. Overcast conditions will also develop as clouds continue to increase in advance of the Pacific storm. Expect overnight minimums to be above the benchmark for mid January, and about 10 degrees warmer than last night. A dry forecast is maintained for Tuesday, but it will be unseasonably warm and humid. The morning fog will give way to a cloud deck with intervals of sunshine in the afternoon. Warm weather fans will delight as maximums reach near 70 for the first time all year. This is a shade warmer than today when readings topped out at in the mid 60s. Winds will be gusty at times in the afternoon as the strong Pacific storm approaches. The influx of Gulf moisture will continue, and as the deeper moisture approaches the forecast area a few showers will be possible by Tuesday night. Fog shouldn't be as much of an issue Tuesday night due to the winds providing mixing of the atmosphere resulting in conditions that will preclude much fog. The period of above normal temperatures will continue as minimums will be in the low to mid 50s, some 10-15 degrees above the normal.
Wednesday is when the next storm system affects the region. The current cut off low and trailing cold front, embedded in the Southern Stream will race Eastward from the Desert SW tonight, and emerge East of the Rockies Tuesday. By mid-week, shower and thunderstorm activity will be on the increase as the front moves into the region. Surface low formation can't be ruled with a great supply of energy from the STJ, but unlike its predecessors which traveled through the Gulf and kept us in the cool sector, this time we'll be well encompassed by the warm sector. The continuing El Nino pattern will add dynamics to an already potent storm system. The energy enhanced system and the presence of a 100 kt. Jet Stream moving right across the area will produce the potential for some severe thunderstorms Wednesday afternoon into Wednesday night. The orientation of the Jet Stream will place the forecast area in the LFQ (Left Front Quad) of the Jet Stream, and this is often a favorable position for severe weather. The air mass over the forecast area will be very unstable on Wednesday, and the advancing warm sector and approaching trough should engender shower and thunderstorm activity Wednesday morning over Texas. This will slide Eastward during the day, and enter our forecast area Wednesday afternoon. The event is close enough now, that I can begin pinpointing a time line for the worst of the weather to occur. My best guess right now is that the thunderstorms will roll through between 3p.m. and 7p.m. The Storm Prediction Center in Norman, OK currently has the forecast area highlighted for a slight risk of severe weather for the day 3 (Wednesday) period. Some 'streamer" or air mass showers will be possible Wednesday morning. The activity will likely congeal into a squall line as it is transported Eastward by the strong Jet Stream. All modes of severe weather will be possible, and with the strong Jet Stream in place certainly wind shear will be possible. This justifies a tornado threat, but I believe the greatest threat from any severe weather will be damaging winds. The 100 kt. winds associated with the Jet Stream means that there will be very gusty winds present on Wednesday. The 100 kt. winds will translate down to the surface via the thunderstorm downdrafts, however, the 100 kt. winds will not be experienced at the surface. Wind speeds decrease with height, and the closer you get the ground, the lesser the wind. That being said, the wind will decrease only so much exponentially, such that winds over 60 mph will still be possible with the strongest storms. The greatest threat for severe weather should be North of the I-10 corridor, but even the immediate coast isn't totally off the hook from severe weather. Further revisions to this forecast will be made on Tuesday. A quick shot of heavy rain is expected, and rainfall amounts for this event should be between 1-2" right on the heels of what we saw this past weekend. The heavy rain isn't the main issue this go around, it's the impinging sever weather threat. The mild weather continues as you would imagine with a severe weather threat, and you can expect a Wednesday maximum in the lower 70s.
The current zonal flow with the STJ streaming overhead is a fast flow. This is the good news, as the system will keep moving off to our East, and continues will improve quickly overnight Wednesday. However, limited cooling is expected behind the front, but it the air will become noticeably drier in its wake. The flow will remain zonal, therefore all the cold air will remain locked up to our North for the time being. Weak CAA takes over late Wednesday night behind the front, and minimums will remain above normal in the low to mid 50s. Skies will clear as high pressure quickly takes over. This will set the stage for quiet weather for Thursday and Friday. It will continue to be springlike as well with highs in the 70s, and lows in the 40s for Friday morning. There will be plenty of sunshine these two days, so that will be nice. Changes occur again by late Friday as the Pacific high shifts Eastward, and we wait for the next in the continuing parade of storms. The Gulf re-opens Friday night with a WAA in earnest as the surface high settles over the SE U.S. Rain chances will remain absent from the forecast this period as the presence of a trigger mechanism is absent for this forecast period. Fog could be an issue once again for the Friday night period, but I defer that decision until after we get past the severe weather episode Wednesday. The unseasonable warmth continues Friday night with moderating minimums back into the 50s with the Gulf flow.
Our next Pacific system will also be quite strong, but it is too early to be specific and say if it will parallel the mid-week system, but with the active STJ and other prominent features of an El Nino you have to figure it might be. Clouds will be on the increase in earnest Saturday as the system comes out of the lee of the Rockies. Saturday could start with some sunshine, but it will likely end on a wet note as this latest trough moves across. If the trough is negatively tilted, then there will be another shot at severe weather Saturday night. Again, this is something I will re-evaluate as we get closer to the event. Best guess right now is that the highest chance of shower and thunderstorms with this system will come Saturday night. It should be another quick mover as well. Another quick inch or two of rain is possible. Strong WAA will be in place ahead of the system, and temperatures could possibly exceed 75. The quick flow carries over through the weekend, and should result in a decent Sunday. A few showers could linger early Sunday, but rapid improvement should occur once again as another high pressure builds in. This is good news for anyone who might want to BBQ outside or have a Saints pre-game party Sunday afternoon before the NFC Championship game that evening! Geaux Saints!!! A bit sharper trough this go around, should result in much cooler air behind the front Saturday night. A great deal of sunshine is expected by Sunday afternoon with temperatures much cooler. Sunday minimums will be around 50, still above normal, but afternoon highs should only be in the lower 60s. The deeper trough will bring about a mix of Canadian and Pacific air in the wake of the Saturday night front, and temperatures by Monday morning with high pressure very near the forecast area will be in the cold category in the mid to upper 30s, reminding us that yes it is still winter! The cool high pressure will keep Monday highs below normal as we round out this forecast period. Looking beyond the scope of this 7 day forecast briefly, a pattern shit next week should result in a transition back towards colder than normal for month's end with another bout of Arctic air still possible the first week of February. The colder pattern could result in a drier pattern, like we've had, but there's an equal chance of the Southern Stream remaining active. Who Dat?
Preliminary Numbers & Zone Forecast:
LCH 48/70 55/72 55/68 0 0 30 80 60 0
LFT 46/71 54/71 56/68 0 0 30 70 70 0
BPT 51/73 57/73 54/70 0 0 40 80 50 0
AEX 45/70 54/70 50/66 0 0 30 80 60 0
POE 47/71 54/71 50/67 0 0 30 80 60 0
ARA 46/71 56/71 58/69 0 0 30 70 70 0
Tonight...Mostly Cloudy with Areas of Dense Fog after midnight. Low 48. Light South wind.
Tuesday...Areas of Dense Fog early, otherwise Mostly Cloudy and Windy. Unseasonably Warm. High 71. SSE wind 15-20 mph and gusty in the afternoon.
Tuesday Night...Cloudy with a 30% chance of shower and thunderstorms. Windy. Low 55. SSE wind 15-20 mph and gusty.
Wednesday...Cloudy, Warm, & Windy with showers and thunderstorms likely. Some severe weather possible in the afternoon. Locally heavy rain at times. High 72. SSE wind 20-25 mph and gusty. Chance of rain 80%.
Wednesday Night...Cloudy with showers and thunderstorms likely in the evening. Some severe storms and locally heavy rainfall possible. Rain ending with skies clearing overnight. Low 55. SSW wind 15-20 mph and gusty becoming NNW at 15-20 mph and gusty in the evening. Chance of rain 60%.
Thursday...Sunny. High 68. North wind 10 mph.
Drew's 7 Day Outlook for Lake Charles & Vicinity
Tuesday
1-19-10
Low: 48
High: 70
Precip: 0%...30% Night
Wind: SSE 15-20
Wednesday
1-20-10
Low: 55
High: 72
Precip: 70%
Wind: SSE 20-25
Thursday
1-21-10
Low: 55
High: 68
Precip: 0%
Wind: N 10-15
Friday
1-22-10
Low: 46
High: 71
Precip: 0%
Wind: NE/SE 5-10
Saturday
1-23-10
Low: 51
High: 74
Precip: 30%...60% Night
Wind: SSE 15-20
Sunday
1-24-10
Low: 49
High: 62
Precip: 20% AM
Wind: NNW 15-20
Monday
1-25-10
Low: 37
High: 55
Precip: 0%
Wind: N 10-15
...Marine Forecast...
Tonight...South winds 10 to 15 knots. Seas building to 2 to 4 feet after midnight. Patchy fog early in the evening...then areas of dense fog after midnight.
Tuesday...South winds 10 to 15 knots. Seas building to 3 to 4 feet in the afternoon. Areas of dense fog. Isolated showers in the afternoon.
Tuesday Night...South winds around 15 knots. Seas 3 to 4 feet. Patchy fog. A chance of showers.
Wednesday...South winds 15 to 20 knots. Seas building to 4 to 5 feet in the afternoon. Showers and thunderstorms likely.
Wednesday Night...Southwest winds 15 to 20 knots. Seas 3 to 5 feet. A chance of showers and thunderstorms.
Thursday...West winds 10 to 15 knots. Seas 2 to 4 feet.
Good night and God bless!
-DM-
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