December-Wet/Stormy New Years Eve Ahead

[Belmer]

if we get snow it'll be when nobody sees it coming. if we see it coming, it won't.

I'm going to have to agree with this.

[srainhoutx]

The Ensembles are still suggesting a rather unsettled pattern across the Intermountain West into the Plains in the medium range. It is interesting to note that there continues to be hints that EPAC moisture over running the shallow cold air mass at the surface providing a rather damp period along the Southern US/Gulf Coast States with an active pattern spreading across the Northern Plains with Clipper action for the Upper Midwest/Great Lakes Region as well as the Central/Northern Rockies. I suspect that areas further N will begin to build some snow pack that may bode well for the late December time frame with less air mass modification for areas S into the Central/Southern Plains.

[srainhoutx]

As for the coming weekend into next week, there is some chatter concerning the lack of run to run consistency and just how things will actually unfold across New Mexico/The Panhandle/The Colorado Front Range into Oklahoma in the cold sector from some NWS offices to our N. The energy (short wave) across the NE Pacific will not move onshore into British Colombia until late Friday into Saturday. There are still some uncertainties as to just how amplifies the trough will be as heights rise S of the Aleutian Islands and if the positive tilted solutions offered of late are in fact correct. Should more energy dive further S into the Great Basin all bets are off regarding a more progressive pattern with a quick moving front and little in the way of moisture.

[wxman57]

I still think the GFS is not handling the upper trof passage on Wednesday properly. Euro still predicts a west Gulf low and a good bit of rain on Wednesday. Looks more reasonable. The lack of run-to-run consistency is with the GFS, not the European. Mostly cloudy skies on Tuesday will likely keep Houston temps above freezing. Huntsville has already reported 32 degrees this year, by the way. Most of Houston will likely see a low on Tuesday around the upper 30s to low 40s.

P.S. SE Texas zone forecast just came out - "Partly cloudy and 65 deg" next Wednesday. I guess the NWS doesn't look at the European model which indicates overcast, steady light-mdt rain and a high in the low 50s.

[srainhoutx]

lol...now the 12Z GFS is back to suggesting the short wave will dive further S into New Mexico with wintry mischief further S in the Southern Rockies/TX Panhandle and maybe even a flurry or two in N TX into Oklahoma. In the warm sector, a line of strong storms also are suggested by the GFS.

12062012 12Z GFS f84.gif

12062012 12Z GFS f90.gif

12062012 12Z GFS f96.gif

12062012 12Z GFS f102.gif

The GFS is also suggesting a potent Western Gulf wave of low pressure as a secondary short wave drops S into the Great Basin next Wednesday/Thursday.

12062012 12Z GFS f174.gif

12062012 12Z GFS f180.gif

12062012 12Z GFS 72 Hour Precip Totals 12zgfsp72192.gif

[srainhoutx]

The 12Z Canadian now joins a deeper digging short wave solution as well. As I mentioned earlier, until this energy gets onshore in British Colombia we will likely see guidance under estimate this system and not have a realistic solution as to the sensible weather expected.

12062012 12Z CMC f90.gif

12062012 12Z CMC f96.gif

12062012 12Z CMC f150.gif

12062012 12Z CMC f156.gif

[wxman57]

12Z GFS is still quite cold for next week, and it adds in a big rain event Thu/Fri:

[srainhoutx]

12Z GFS is still quite cold for next week, and it adds in a big rain event Thu/Fri:

It does appear the long awaited pattern change will in fact be here next week. The Ensembles (both GFS and Euro as well was the CFSv2) suggest we are headed toward a much more active pattern and some roller coaster type temp swings as we head into the remainder of December. I guess those of us that like warmer weather are just going to have to deal with it. I do see the Plains getting into a snowy active pattern as well meaning less air mass modification as the month moves forward.

[MontgomeryCoWx]

Happy Dances in this office!

[srainhoutx]

Well the 12Z Euro is continuing the trend of a more southern solution offered by the GFS and Canadian. It could make for and interesting late weekend/next week across the Southern Rockies/Southern Plains and into the Texas/Louisiana areas in the 'warmer' sector.

12062012 12Z Euro f96.gif

[Belmer]

Looks like the week after next (~18-23) another Canadian/Arctic blast with some pretty good snowfalls for us here in south TX. According to the 00z cfvs2.

I do believe the pattern change has arrived. Hope we get an exciting winter this year.

[srainhoutx]

EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
202 PM EST THU DEC 06 2012

VALID 12Z SUN DEC 09 2012 - 12Z THU DEC 13 2012

THE MEDIUM RANGE PERIOD CONTINUES TO FEATURE A STABLE AND WELL
AGREED UPON LARGE SCALE PATTERN FEATURING AN ERN PAC MEAN RIDGE
AND POSITIVELY TILTED NOAM MEAN TROF WELL INTO NEXT WEEK. THERE
IS LOWER CONFIDENCE WITH INDIVIDUAL SHORTWAVES PROGRESSING AROUND
THE TOP OF AN AMPLIFIED ERN PACIFIC RIDGE AND CONTINUING INTO THE
DOWNSTREAM MEAN TROF...THOUGH ENOUGH CLUSTERING EXISTS TO IDENTIFY
THREE PRIMARY FEATURES LIKELY TO BE OF INTEREST THRU NEXT TUE.

THE LEADING SYSTEM WILL DEEPEN AS IT TRACKS FROM THE PLAINS/MS
VALLEY INTO ERN CANADA DURING DAYS 3-5 SUN-TUE. THE 00Z ECMWF
LEANS SLIGHTLY ON THE FASTER SIDE OF THE SPREAD WHILE THE 00Z AND
12Z UKMET RUNS REMAIN ON THE SLOWER SIDE. THE GEFS/ECMWF ENSEMBLE
MEANS HAVE BEEN FAIRLY STEADY IN DEPICTING AN INTERMEDIATE
SOLUTION AND ARE CERTAINLY WORTH SOME WEIGHTING IN THE FORECAST
GIVEN CURRENT SPREAD AND MODEL VARIABILITY OVER RECENT DAYS.
MULTI-DAY TRENDS LEAN A LITTLE FASTER AS A WHOLE SO PARTIAL
ACCOUNT WAS GIVEN TO THE 00Z GFS/ECMWF. THIS SOLUTION IS NOW
INCREASINGLY MUDDLED WITH THE LATEST 12Z ECMWF NOW SWITCHING TO A
SLOWER/MORE DEFINED LOW SOLUTION MORE IN VEIN WITH THE UKMET.
THIS SOLUTION WAS NOT DEPICTED IN HPC PROGS GIVEN THE MEAN
LONGWAVE FLOW SEEMS LESS THAN FAVORABLE AMID UNCERTAINTY...BUT IS
STILL IS A POSSIBLE SOLUTION THAT WOULD OFFER A MUCH WETTER PCPN
PATTERN.

[srainhoutx]

The 18Z NAM (WRF/NMM) as well as the 18Z GFS have trended a tad further S and W with a potent vort max into New Mexico. These trends in the solutions today suggest a bit more in the way of moisture and even 'hint' that there may be some post frontal moisture in the cold sector further to our N and W. Forecast confidence is very low and expect changes during the next 24-48 hours until the disturbance actually gets onshore in Western Canada and enters the RAOB network. As far as the cold Canadian Airmass, that is the easy aspect of the forecast other than timing issues that is typical in guidance in handling cold dense air. We here in Central and SE Texas and even into West Central Texas will likely see temps plunge from the 70's to the mid to low 40's in a very short period of time suggesting this will be the first Blue Norther of the season for the Southern Plains.

[Ptarmigan]

12Z GFS is still quite cold for next week, and it adds in a big rain event Thu/Fri:

Let's hope it rains next week.

[mckinne63]

Cold AND rain? Bonus!

[JackCruz]

Wait, I'm confused are talking about COLD and RAIN here in SE Texas? Or just north?

[Baseballdude2915]

Wait, I'm confused are talking about COLD and RAIN here in SE Texas? Or just north?

The GFS model shows a respectable cold front coming through this Sunday afternoon knocking us into the 50s/30s for a few days, the front will bring a bit of rain with it, around .25''. A MUCH larger rain event was shown for Friday the 14th but has been pushed back a few days. From how I usually interpret it the GFS usually has trouble finding the exact timing of major events that are over a week out this time of the year.

Overall, looks we are in for pattern changes, chilly air, and wet weather to end the year! Its about time.

And as always *amateur opinion* shown above.

[Belmer]

The 00z NAM looks a little encouraging tonight for those up in the northern viewing area and off to our West near the hill country hoping for maybe a sleet pellet or two. Maybe a flurry?



That above is showing hour 84 on Monday. So at best, it would be Monday evening, ...while the temperatures continue to drop.
If we don't get any wintery fun this December, it looks like we'll probably have to wait till February.
January is usually pretty boring as far as precip goes and cold air.

[srainhoutx]

For the night crew...keep an eye on the overnight guidance. The long range NAM (WRF/NMM) is hinting a stronger vort max digging a tad further S and perhaps a Coastal wave developing near the Middle Texas Coast as the front passes. That could be a new wrinkle in the forecast and something to monitor. The ramifications further N and W in the cold sector could provide a slightly better chance of some light wintry mischief for portions of N TX and OK. We will see.

[Belmer]

For the night crew...keep an eye on the overnight guidance. The long range NAM (WRF/NMM) is hinting a stronger vort max digging a tad further S and perhaps a Coastal wave developing near the Middle Texas Coast as the front passes. That could be a new wrinkle in the forecast and something to monitor. The ramifications further N and W in the cold sector could provide a slightly better chance of some light wintry mischief for portions of N TX and OK. We will see.

Just posted an image of the NAM for Monday, Srain. Looks exciting. Hope it continues to get more colorful for us.