Texas winter wx thread (2009-2010)

[LaBreeze]

For those of you texas winter weather lovers, the GFS 00Z run forecast the blizzard of the century covering almost the entire state of Texas around the new year.

Not seeing this at all. I just don't see this happening in any way - always nice to wish, I guess.

[vbhoutex]

For those of you texas winter weather lovers, the GFS 00Z run forecast the blizzard of the century covering almost the entire state of Texas around the new year.

Not seeing this at all. I just don't see this happening in any way - always nice to wish, I guess.

Are you saying you don't see it on the model or you don't see it happening?

[Ntxw]

For those of you texas winter weather lovers, the GFS 00Z run forecast the blizzard of the century covering almost the entire state of Texas around the new year.

Not seeing this at all. I just don't see this happening in any way - always nice to wish, I guess.

Are you saying you don't see it on the model or you don't see it happening?

The models are showing it, he's saying he doesn't trust it to happen.

[cheezyWXguy]

For those of you texas winter weather lovers, the GFS 00Z run forecast the blizzard of the century covering almost the entire state of Texas around the new year.

Not seeing this at all. I just don't see this happening in any way - always nice to wish, I guess.

Are you saying you don't see it on the model or you don't see it happening?

lol yeah, cuz the model defintely shows it. That doesnt mean its even close to verification though.

[LaBreeze]

Right, Ntxw. I've learned to take those models very lightly - not much trust in them.

[vbhoutex]

Labreeze, see my post in the deep south thread concerning the above model run.

[iorange55]

The new ECMWF looks different to me it's slower, and it looks like it's more south with the track, and possibly colder. But that's all I can really elaborate on the ECMWF

[srainhoutx]

The new ECMWF looks different to me it's slower, and it looks like it's more south with the track, and possibly colder. But that's all I can really elaborate on the ECMWF

Correct. The Low is now shown near Central TX versus the Panhandle. It is certainly slower and much colder than it has been. A complete flip of the GFS and the previous EC runs. What raises an eyebrow is the almost stalling of the unphased lows near IA. That is sending the cold air S. Also note the Upper Low near Baja/S CA on the 31st. That may be what the GFS was sniffing out tonight. We shall see. There will be more Upper Air Data ingested into the data sets the next couple of days. I do see a forecasting challenge ahead and we may infact not know how this will play out until 24-36 hours out. Good night folks. Tomorrow is another day. Work day that is.

[srainhoutx]

Early morning Prelim Extended HPC Disco...biting on the slower ECMWF solution as well as Ensembles...for now....

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
504 AM EST MON DEC 21 2009

VALID 12Z FRI DEC 25 2009 - 12Z MON DEC 28 2009


USED THE 00Z/21 ECMWF AND 12Z/20 EC ENSEMBLE MEAN TO CONSTRUCT THE
PRELIMINARY FRONTS AND PRESSURES FOR DAYS 3 THROUGH 7. THE
EUROPEAN CENTRE GUIDANCE HAS VERIFIED WELL OVER THE LAST SEVERAL
MONTHS...AND SEE NO REASON TO MISTRUST THE RECENT RUNS. THE ECMWF
AND UKMET ARE SLOWER AND MORE SUPPRESSED WITH THE BIG LOW CROSSING
THE SOUTHERN PLAINS DAY 3...A BETTER FIT TO THE BLOCKING PATTERN
THAN THE GFS AND GEM GLOBAL. THE CYCLONE SHOULD REACH ITS PEAK
INTENSITY AND COVERAGE DAY 4 OVER THE MIDWEST...BEFORE SQUEEZING
THROUGH THE BLOCK OVER THE GREAT LAKES AND NORTHEAST. THE STORM
LOOKS LIKE A WHOPPER...WITH STRONG WINDS AND HEAVY SNOWS ON THE
BACKSIDE OF THE SYSTEM...AND SNOW AND ICE ON THE NORTHEAST SIDE.
WITH THE AMPLIFICATION OF THE WEST COAST RIDGE LATE IN THE
PERIOD...THE ONLY FRESH FLOW FROM THE WEST WILL BE EITHER OVER THE
TOP...IN THE FORM OF ARCTIC AIR...OR UNDERNEATH...WITH DIFFUSE
ENERGY SLIDING TOWARD SOUTHERN CALIFORNIA.

CISCO

[iorange55]

this looks like such a good storm we might just miss out on! Come on models change, change, change.

[srainhoutx]

Looking a bit longer range into the New Years time frame it does appear that the Arctic Regions will reload and the STJ will kick in offering an interesting pattern via the ensembles. Remember what we saw last night on the 00Z GFS for New Years Day and beyond...

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
805 AM EST MON DEC 21 2009

VALID 12Z FRI DEC 25 2009 - 12Z MON DEC 28 2009

TELECONNECTIONS WITH A POSITIVE ANOMALY CENTER IN THE LOWER 50S
LATITUDE IN WESTERN CANADA FAVOR A PROGRESSIVE CLOSED CYCLONE TO
ITS SOUTH MOVING INTO THE SOUTHWEST. AMPLIFIED RIDGING IN WESTERN
CANADA ALSO FAVORS TROUGHING IN THE PLAINS/MIDWEST...AND A STORM
TRACK WEST OF THE APPALACHIANS THROUGH THE GREAT LAKES WITH
PRECIPITATION PREFERRED ACROSS THE EASTERN HALF OF THE COUNTRY
NEAR AND EAST OF THE TROUGH AXIS. THE MODELS /OUTSIDE THE 06Z
GEFS MEAN WITH THE STORM TRACK/ GENERALLY AGREE ON THESE
IDEAS...THOUGH THE GUIDANCE MOST AGREEABLE TO THIS CONCEPTUAL
MODEL ARE THE 00Z ECMWF AND ITS ENSEMBLE MEAN...PARTICULARLY WITH
THE LOW TRACK IN THE MIDWEST/GREAT LAKES.

AFTER FURTHER CONSULTING THE 00Z MULTI-MODEL ENSEMBLE
MEMBERS...THE 00Z ECMWF APPEARS TO BE TOO FAR EAST WITH ITS LOW
TRACK IN THE MIDWEST. WHILE THE ECMWF HAS BROKEN CONTINUITY WITH
A CLOSED LOW WHICH SOMEHOW SEPARATES FROM ITS PARENT CENTER IN
NORTH-CENTRAL CANADA AND DIVES IT SOUTHWARD LATE IN THE
PERIOD...IT HAS SHOWN BETTER CONTINUITY ELSEWHERE...AT LEAST
POSITION-WISE. DEPTH-WISE...THE ECMWF SHOWS SIGNIFICANT ISSUES IN
THE EASTERN PACIFIC WITH THE DEEP CYCLONE UNDERCUTTING THE RIDGING
IN WESTERN CANADA...SHOWING STRONGER SOLUTIONS ON ITS 12Z RUNS
THAN ITS 00Z RUNS OVER THE PAST COUPLE DAYS. THE 06Z GFS/06Z GEFS
MEAN WERE MUCH QUICKER THAN THE REMAINDER OF THE GUIDANCE...BUT
BECAUSE ANY POSSIBLE KICKER TO THIS SYSTEM IS STILL ABOUT 1500 NM
UPSTREAM ACROSS THE CENTRAL PACIFIC EARLY NEXT WEEK...A SLOWER
SOLUTION SIMILAR TO THE ECMWF WAS PREFERRED. BECAUSE OF
THIS...THE MANUAL PROGS STARTED WITH A 70/30 BLEND OF THE 00Z
ECMWF ENSEMBLE MEAN/00Z ECMWF...BEFORE REFINEMENTS WERE MADE TO
KEEP PRESSURES/WINDS REALISTIC AND CLOSER TO THE CENTER OF THE
SPREAD BOTH IN POSITION AND DEPTH OF LOW PRESSURE CENTERS. THE
00Z GEFS MEAN IS A REASONABLE ALTERNATIVE TO THE 00Z ECMWF
ENSEMBLE MEAN. THIS PREFERENCE LEADS TO GREATER WARMING ACROSS
MONTANA THAN SHOWN IN THE 00Z GFS-BASED MOS...YET MAINTAINS
REASONABLE CONTINUITY.

ROTH

[srainhoutx]

I'll repost the morning e-mail from Jeff in this Topic as it is relevant to the dicussions in the TX thread regarding temps and any potential shortwave activity just beyond Christmas Day ...

Cold and dry air mass over the region will begin to modify today as surface high pressure cell overhead moves eastward. Already have southerly winds returning to the area and expect moisture levels to begin to increase this afternoon. Longwave trough will deepen over the Rockies over the next 48 hours with a strong upper level storm system developing over the 4 corners area and then track E to ENE across TX Wed/Thurs. This system will bring a late week blizzard across much of the Midwest and pour could polar air southward into the southern plains by Thursday.



Approaching upper level trough will activate a southerly low level jet this evening with low clouds quickly filling in after midnight. Will see low temperatures prior to midnight and then a slow warming as clouds thicken and warm air advection increases. Mostly cloudy Tuesday with a few showers possible. Surface dewpoints will likely begin to close in on the lower 60’s by late Tuesday and this will bring a bout of sea fog to the bays and coastal waters where water temperatures are in the upper 50’s.



Impressive storm system and jet stream dynamics come to bear across the region Wed as a strong upper level low moves across NW TX with surface low pressure developing over SC TX and track NE toward the ARKLATX region. SE TX will be warm sectored with mid 60 degree dewpoints pouring northward. Expect dense sea fog to lock in the bays from Tuesday evening-Wed evening as dewpoints exceed coastal water temps. 250mb winds become strongly divergent Wed afternoon with strong speed and directional shear across the area. Factors holding back a big severe outbreak appears to be quality of Gulf moisture return as previous fronts have done a number on the moisture pool over the Gulf. Feel the models may possibly be under-estimating the degree of moisture return and a higher severe threat may be warranted for the Wed PM time period. Will need to keep a close eye on this over the next 24-36 hours as low level helicity values would be supportive of supercells and tornadoes.



Next item of concern is how much cold air drops southward behind this system and how cold does it get by the end of the week. GFS has been trending warmer with this post frontal air mass and the general agreement now is that a Pacific front will cross the area Wed PM taking temperatures for Christmas Eve into the 50’s followed by the lagging polar air arriving late Christmas Even into early Christmas Day. GFS may be too warm with this air mass especially when considering the large snow event that will be ongoing north over the plains as far south as OK…so I still like the colder side of things although maybe not freezing on Christmas morning. GFS along with other guidance has at time been hinting that a short wave may drop down the backside of the trough the 26/27 with the cold air in place. 00Z runs of the GFS is back on the dry side this go around…but it has been flipping nearly 180 degrees with each run. Not sure there will be much moisture to work with although the formation of a NW Gulf surface trough is possible. For now will go with the drier side of guidance with maybe an increase in clouds Saturday. This period also bears close watch as stronger lift and moisture could result in the possibility of winter precipitation, but this is highly uncertain and a very low confidence forecast when compared to the Dec 4 event.

[Portastorm]

I've lost what little confidence I had in the GFS beyond 72-96 hours out in terms of nailing down low pressure development and tracks. IIRC, 10 days out from the Dec. 19-20th time period we were supposed to see some kind of winter storm per the GFS in at least the northern part of Texas. Didn't materialize. In fact, the low developed in the NW Gulf, created some decent rain for the southeastern half of the state and that was it. Then, 10 days from Christmas, the GFS suggested a winter storm for the state again. Well, we're seeing now it is likely to be dry and the other possibly "winter" weather is a longshot along the Red River.

Now, the GFS is promising us wintry weather after Christmas. 10 days out ... hmm, if you want to talk "trends", do you see the trend here?!

The month of December has been remarkable for Texas in that we've been 5-8 degrees below normal for temperatures. Generally the models have done well by that standard in suggesting below normal temps. But in terms of storm systems ... I'm almost convinced it is a crapshoot beyond 3-4 days. I expect more below normal temps for the next two weeks but am highly skeptical of any potential storm system until it's showing 72 hours out.

Lucy's (GFS' promises of winter storms in Texas) already gotten me several times this month. My backside needs a rest!

[cctxhurricanewatcher]

I've lost what little confidence I had in the GFS beyond 72-96 hours out in terms of nailing down low pressure development and tracks. IIRC, 10 days out from the Dec. 19-20th time period we were supposed to see some kind of winter storm per the GFS in at least the northern part of Texas. Didn't materialize. In fact, the low developed in the NW Gulf, created some decent rain for the southeastern half of the state and that was it. Then, 10 days from Christmas, the GFS suggested a winter storm for the state again. Well, we're seeing now it is likely to be dry and the other possibly "winter" weather is a longshot along the Red River.

Now, the GFS is promising us wintry weather after Christmas. 10 days out ... hmm, if you want to talk "trends", do you see the trend here?!

The month of December has been remarkable for Texas in that we've been 5-8 degrees below normal for temperatures. Generally the models have done well by that standard in suggesting below normal temps. But in terms of storm systems ... I'm almost convinced it is a crapshoot beyond 3-4 days. I expect more below normal temps for the next two weeks but am highly skeptical of any potential storm system until it's showing 72 hours out.

Lucy's (GFS' promises of winter storms in Texas) already gotten me several times this month. My backside needs a rest!

GFS= Garbage Forecasting System

[msstateguy83]

i agree the gfs long range has become nothing but garbage... i think more closely we need to be looking at
what is right in front of us the major storm system that COULD bring significant accumulations to oklahoma
and portions of northern,northwestern tx wed-late christmas eve. the track of the upper level low will
determine pretty much everything a track 100-150 mi n or s could be huge in who gets what kinda precip
and how much. so just stay tuned iam looking over the morning runs rightnow to see what i think, but
just looking at oun's sws and morning discussion it looks like they are also thinking a major winter storm
is becoming more,more likely.

[TexasStorm]

i agree the gfs long range has become nothing but garbage... i think more closely we need to be looking at
what is right in front of us the major storm system that COULD bring significant accumulations to oklahoma
and portions of northern,northwestern tx wed-late christmas eve. the track of the upper level low will
determine pretty much everything a track 100-150 mi n or s could be huge in who gets what kinda precip
and how much. so just stay tuned iam looking over the morning runs rightnow to see what i think, but
just looking at oun's sws and morning discussion it looks like they are also thinking a major winter storm
is becoming more,more likely.

Other than the Red River counties such as Grayson County, I do not see anyone south of the Oklahoma/Texas border getting anything. The models really have not changed much over the last 48 hours.

[CaptinCrunch]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
1027 AM CST MON DEC 21 2009

.UPDATE...
QUICK UPDATE TO TWEAK CLOUDS AND TEMPS. PACKAGE ON TRACK.
PRELIMINARY LOOK AT 12Z NAM/GFS SHOWS NO MAJOR CHANGES IN STORM
TRACK OR SEVERE POTENTIAL FOR EASTERN HALF OF NORTH TX. 84

[gofrogs]

Yeah nothin doin for texas forthe next few weeks imho

[cycloneye]

For those who like to follow about what El Nino is doing here (Steve,Portastorm) are this week numbers.No big changes from last week ones.

Climate Prediction Center Weekly update at 12/21/09

Last Week Numbers:


Niño 4= +1.3ºC
Niño 3.4= +1.8ºC
Niño 3= +1.6ºC
Niño1+2= +0.2ºC

This Week Numbers:


Niño 4= +1.4ºC
Niño 3.4= +1.8ºC
Niño 3= +1.6ºC
Niño 1+2= -0.2ºC

[srainhoutx]

For those who like to follow about what El Nino is doing here (Steve,Portastorm) are this week numbers.No big changes from last week ones.

Climate Prediction Center Weekly update at 12/21/09

Last Week Numbers:


Niño 4= +1.3ºC
Niño 3.4= +1.8ºC
Niño 3= +1.6ºC
Niño1+2= +0.2ºC

This Week Numbers:


Niño 4= +1.4ºC
Niño 3.4= +1.8ºC
Niño 3= +1.6ºC
Niño 1+2= -0.2ºC

Thanks Luis. Fits nicely with the reloading process we are expecting in the early/mid January time frame.