Southern States - LA-MS-AL-GA-TN Winter Storm Potential

[GeneratorPower]

Hello, fellow Southerners. There have been a few of us looking for the very latest on potential Winter Weather for the Southern States. I will be posting updates here taken from AFDs (Area Forecast Discussions) put out by NWS offices in the south. Generally, I'd like to mention GFS trends, AFD trends, etc.

The states covered by my research will include:

Louisiana
Mississippi
Alabama
Georgia
Tennessee

Specifically, it will focus on the area from Interstate 20 to Interstate 40. So if you're NORTH of I-20 but SOUTH of I-40, I will make every effort to include your AFD when it mentions Winter WX.If you are SOUTH of I-20, I would encourage you to post your AFD for all to read. This is because whatever affects you usually moves NE and affects our area. Generally, folks north of I-40 would be beyond the scope of this thread.

I won't be making forecasts, but if one appears, it is not official and shouldn't be treated as such!

[GeneratorPower]

Chattanooga not forecasting Winter WX but should keep in mind forecast confidence is low.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
240 PM EST SUN JAN 21 2007


.LONG TERM (WEDNESDAY THROUGH SUNDAY)...CONFIDENCE REMAINS QUITE LOW
FOR EXTENDED PERIOD...MAINLY IN TRACK AND TIMING OF SYSTEM MOVING
THROUGH THE REGION AROUND THE WEDNESDAY/THURSDAY TIME FRAME.

[GeneratorPower]

Looking quiet right now from all AFDs in the area. Will post when something turns up.

[icicle]

greetings. my first post, and I thought I would share this long range outlook for north Ms.

SUN AND INTO NEXT WEEK...ALL OF THE MEDIUM RANGE MDLS AND NOW IN
DECENT AGREEMENT WITH THE UPPER FEATURES IN THIS TIME PERIOD. IT
LOOKS LIKE THERE WILL BE SOME BROAD TROUGHING OVER THE ERN CONUS
WITH FLATTER UPPER FLOW OVER OUR AREA SUN AND INTO THE EARLY PARTS
OF NEXT WEEK. ALSO THERE WILL BE A DECENT SFC HIGH PUSHING SOUTH
INTO THE PLAINS...1040+ BY THE GFS AND 1035+ BY THE ECMWF. THIS
WOULD SUGGEST THAT NEXT WEEK MAY BEGIN RATHER COLD. SOMETHING TO
NOTE IS THAT TELECONNECTIONS AND OTHER LONG RANGE FORECASTING
METHODS ARE SUGGESTING A RATHER COOL TO COLD PATTERN SETTING UP FOR
THE REMAINDER OF THE MONTH AND INTO FEB.

AS FOR TEMPS AND POPS...WITH THE WAY THE MDLS HAVE BEEN JUMPING
AROUND AND CONFIDENCE BEING FAIRLY LOW I HAVE JUST DEFERRED TO GUI.
I DO NOT FEEL CONFIDENT ENOUGH TO REMOVE OR INCREASE POPS ANY WHERE
BUT WILL KEEP A CLOSE EYE ON POPS SAT AND THEN TEMPS FOR NEXT WEEK.
SPEAKING OF NEXT WEEK...RIGHT NOW THE MEX IS RIGHT AROUND THE
ENSEMBLE GUI. IF THE MDLS CONTINUE TO INDICATE THIS SFC HIGH PUSHING
SOUTH THROUGH THE PLAINS AND INTO THE MID AND LOWER MS RIVER VALLEY
WE MAY NEED TO LOWER TEMPS CONSIDERABLY

not official.

[rsdoug1981]

A much needed thread, GeneratorPower!

Icicle,

I suppose I may have been in your neck of the woods the other day. It started sleeting quite heavily and even snowing here in Canton, so I decided to try to chase some snow. I went as far north as Winona and turned around. I never saw anything more than what I saw in Canton. Anyway, welcome!

[icicle]

thanx for the welcome. yes we had some very light sleet mixed in with the rain, the temps were in the mid 40's as well, weird stuff.

A much needed thread, GeneratorPower!

Icicle,

I suppose I may have been in your neck of the woods the other day. It started sleeting quite heavily and even snowing here in Canton, so I decided to try to chase some snow. I went as far north as Winona and turned around. I never saw anything more than what I saw in Canton. Anyway, welcome!

[GeneratorPower]

NWS Huntsville 2am 1/22/2007 AFD. Seems to reflect what icicle was saying. February should start off colder than normal.

A PREVIEW OF EARLY NEXT WEEK...BOTH THE ECMWF AND GFS ARE INDICATING
A TROF DIVING SWD INTO THE LOWER 48 FROM NRN CANADA AND BRINGING A
1040+MB SFC HIGH INTO THE CENTRAL PART OF THE COUNTRY. SO IT LOOKS
LIKE MORE COLD WEATHER IS ON ITS WAY INTO THE TN VALLEY NEXT WEEK.

[GeneratorPower]

See TX Ice Storm Thread, Thread #9, page 7. wxman57 is mentioning the possibility of ice for the deep south next week.

[HarlequinBoy]

Ah, thanks GP for this thread!

[rsdoug1981]

The mid level flow on the much maligned 18z GFS nearly matches the 12z Euro at the 10 day mark.

For kicks and giggles:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _240.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _252.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _264.shtml

I'm beginning to believe in a decent cold outbreak around the first of the month. It looks like the cross polar flow will be going strong around that point.

In addition, check out the NAO:

http://www.cpc.ncep.noaa.gov/products/p ... .sprd2.gif

It's finally headed into negative territory for the first time in a while. Maybe the next shot of cold will be the real deal.

[GeneratorPower]

rsdoug1981, I'm seeing the same thing. Winter looks to be hanging around for a while.

Peachtree City, GA mentions a bit of Winter WX.

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
627 PM EST MON JAN 22 2007

...EDITED BY GENERATORPOWER...

THE
APPROACH OF A SHORT WAVE AND COLD FRONT WILL NEED TO BE WATCHED FOR
LATE SATURDAY INTO SUNDAY. OVERALL MOISTURE LOOKS TO BE LIMITED
EXCEPT WITH THE SHORT WAVE WHICH WILL AFFECT MAINLY FAR N GA
LATE SATURDAY/EARLY SUNDAY. DEPENDING ON ACTUAL TIMING OF EVENT AND
IF PRECIP IS PRODUCED...SOME MIX OF WINTER PRECIPITATION COULD
OCCUR.

Memphis has some neat stuff...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEMPHIS TN
315 PM CST MON JAN 22 2007

.LONG RANGE...(FRIDAY THROUGH MONDAY)...LONG RANGE MODELS FEATURE AN
UPPER LEVEL PATTERN WITH NORTHWEST FLOW ALOFT THROUGH THE PERIOD
WITH AN UPPER LEVEL LOW MOVING THROUGH THE LOWER MISSISSIPPI VALLEY
SATURDAY INTO SUNDAY. AT THE SURFACE A COLD FRONT WILL PASS THROUGH
THE REGION SATURDAY AND INTRODUCED LOW END POPS INTO THE FORECAST.

[baygirl_1]

I greatly appreciate y'all posting the forecast discussions for upstate. We're heading to Auburn this weekend and Birmingham next week. It's looking like it's going to get much colder and wxman57's mention of ice in the Deep South is worrisome and exciting at the same time. We south Alabama folks haven't a clue what to do with white stuff, unless it's the white sand over at Orange Beach!

[Jagno]

See TX Ice Storm Thread, Thread #9, page 7. wxman57 is mentioning the possibility of ice for the deep south next week.

For weather dummies like me can someone reference those maps they're talking about and apply it to SW Louisiana? I'm south of I-10. I love keeping ahead of the weather whenever possible and being ready.

[rsdoug1981]

Jagno,

Check out the map wxman posted in this thread.

http://www.storm2k.org/phpbb2/viewtopic ... &start=120

It's far too early to determine possible temps and precip, but the general theme of the major models is to carry a very cold air mass into the lower 48 around the 1st of February.

When you look at wxman's post with the European model, you can see that the blue lines stretch from northern Canada all the way down to the Gulf Coast. That indicates that there will be cross polar flow. In other words, there will be a mass of cold air from Siberia that crosses the North Pole and heads south. These cold air masses are very dense and typically travel all the way to the southern US.

The model that wxman posted also indicates that the southern branch of the jet stream may carry some moisture from the Pacific to the southern US around the same time the cold air may arrive.

The bottom line is that it *may* get substantially colder in the near future, and there *may* be some moisture around when the cold air arrives. We won't know the particulars for some time.

[rsdoug1981]

Again, for kicks and giggles. Note the 1056mb high in the west. Assuming a basic 1:10 liquid/snow ratio, I'd have close to 6 inches of snow at my house. This would be one we talk about for awhile...

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _252.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _264.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _276.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _288.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _300.shtml

I'm still not thrilled to death, but I think it's definitely going to get chilly. I like the model consistency of the upper and middle flow...not even thinking about surface features yet.

Oh yeah... how about some lows in the teens all the way down to SELA?

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _324.shtml

[vbhoutex]

If that verifies-YIKES!!!!!

[Jagno]

Thanks for the informative posts. I've seen all the maps but I'm still not experienced enough to translate them. In short, to the amature, we are grateful for the simple explanations and breakdowns you folks give us until we can gain the knowledge and experience to decipher them ourselves. I'll keep a watchful eye on this thread. BTW, thanks for posting this thread.

[icicle]

Whoa, it will be even worse up here at tupelo....Brrrrr.

Again, for kicks and giggles. Note the 1056mb high in the west. Assuming a basic 1:10 liquid/snow ratio, I'd have close to 6 inches of snow at my house. This would be one we talk about for awhile...

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _252.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _264.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _276.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _288.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _300.shtml

I'm still not thrilled to death, but I think it's definitely going to get chilly. I like the model consistency of the upper and middle flow...not even thinking about surface features yet.

Oh yeah... how about some lows in the teens all the way down to SELA?

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _324.shtml

[rsdoug1981]

From KJAN morning AFD:

IT STILL LOOKS LIKE AN EVEN COLDER AIR MASS MAY BE ON THE WAY AROUND THE MIDDLE OF THE WEEK AS THE POLAR LOW SITUATES OVER THE HUDSON BAY ALLOWING VERY COLD ARCTIC AIR TO PLUNGE SOUTH THROUGH CANADA AND INTO THE NRN CONUS. GFS SHOWS ANOTHER PIECE OF ENERGY TRYING TO CUTOFF OVER THE DESERT SW BUT THIS ACTUALLY REMAINS PHASED WITH THE BROAD L/W TROUGH DEVELOPING. ONCE AGAIN B/C OF THIS FEATURE THE MDLS ARE SHOWING THE POSSIBILITY OF THE FCST BECOMING INTERESTING LATE NEXT WEEK. WITH VERY COLD AIR TRYING TO PUSH DOWN HERE...THE COLD AIR WOULD BE IN PLACE WHILE THIS ENERGY OVER THE DESERT SOUTHWEST TRIES TO ROUND THE TROUGH AND MOVE TWRDS THE LOWER MS VALLEY. NOT THAT THIS IS UNUSUAL SINCE THE GFS CONSISTENTLY TRIES TO DEVELOP WINTER PRECIP OVER OUR AREA AT 10 DAYS OUT BUT THE PATTERN WE HAVE BEEN IN AND THE WAY EVERYTHING IS TRYING TO SET UP IT WILL BE INTERESTING TO WATCH HOW THIS EVOLVES NEXT WEEK. ALSO THE ECMWF IS QUITE SIMILAR ESPECIALLY THE 12Z BUT THE NEW 00Z HOLDS THE UPPER LOW/ENERGY BACK IN THE SW.

[icicle]

sounds great, except for the 00Z....ACCu weather has sleet/snow/frz rain for feb 1st in my area (northeast ms), and again on feb 3rd, with high temps around 40.