Texas winter wx thread (2009-2010)

[srainhoutx]

Nice meso northwest of Palestine, TX.

We're following all the mess on the USA Weather side txagwxman...could use some help...

viewtopic.php?f=24&t=107419

[srainhoutx]

The signals a getting rather strong now of a switch back to a colder pattern. The latest GFS run was showing hints of a 1048mb+ High Pressure in AK. The HPC now mentioning a return to a colder pattern as well...

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
223 AM EST THU JAN 21 2010

VALID 12Z MON JAN 25 2010 - 12Z THU JAN 28 2010


THE PRELIMINARY FRONTS AND PRESSURES FOR DAYS 3 THROUGH 7 WERE
BASED PRIMARILY ON THE 00Z/21 ECMWF...WITH A MODEST INCORPORATION
OF THE 12Z/20 EC MEAN LATE IN THE PERIOD TO REFLECT THE
UNCERTAINTY IN SYNOPTIC DETAIL INHERENT TO THAT TIME RANGE. THE
ECMWF HAS BEEN THE MOST CONSISTENT OF THE GLOBAL NUMERICAL MODELS
WITH THE HANDLING OF THE SPRAWLING CYCLONE OVER THE NATIONS
MIDSECTION EARLY IN THE FORECAST...AND ALONG WITH THIS GOOD
CONTINUITY...THE EUROPEAN CENTRE GUIDANCE HAS HAD A STRONG RUN OF
VERIFICATION SINCE THE START OF THE CURRENT COLD SEASON. THE
GATES TO THE PACIFIC WILL CLOSE THIS PERIOD...WITH A
COLDER...DRIER FLOW SETTING UP OVER THE CONTIGUOUS UNITED STATES.


CISCO

[srainhoutx]

The 00Z EC vs GFS 500mb means are beginning to latch on to a Cross Polar Flow. Will be interesting to watch future guidance to see just how strong of a cold pattern we may see here in TX...

[Portastorm]

Yeppers srainhoutx, the 12z GFS continues the trend. Looks like a nice little winter weather event for north Texas at the 180-192 hour timeframe.

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/12/model_l.shtml

[natlib]

San Angelo office mentions possibility of Arctic air by the middle of next week.

[Portastorm]

Today's 0z Canadian (CMC) also showed a similar scenario.

http://www.meteo.psu.edu/~gadomski/CMC_0z/cmcloop.html

[srainhoutx]

AO in beginning to tank again (-1.549 today) and the EPO is now showing a negative signal as well(This suggests a Cross Polar regime). With the ongoing SSW/MMW event in the Upper atmosphere, the guidance is beginning to latch on to a colder solution toward the end of January/early February. After my natural gas bill for last month as well as the frozen pipe issues that many in my area are dealing with from the last event, I'm not too sure that I'm ready for this again. Hopefully it will not be as bitter cold as January was. Enjoy the warmup while it lasts.

[Ntxw]

These next few powerful storms should lay some more snow cover to our north. It's like things are falling into place all over again :lol.: There's also stratospheric warming expected which usually means colder weather. Also the storm Portastorm mentions was on 0z last night also. Any doubts about this year's el nino especially in southern California which expected rain is getting more than they can handle even though it came a bit late for them.

[srainhoutx]

HPC thoughts this afternoon...still some uncertainty at this range with the 'finer details'...

EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
227 PM EST THU JAN 21 2010

VALID 12Z SUN JAN 24 2010 - 12Z THU JAN 28 2010


THE MEAN LONGWAVE PATTERN SHOWS THE DOMINANCE OF THE VERY STRONG
SUBTROPICAL JET ACROSS THE SRN CONUS WEAKENING BY TUE DAY 5...AS A
500MB BLOCKING HIGH/RIDGE FORMS OVER THE NE ALASKAN COAST. BY
TUE...CANADIAN ENERGY DROPPING SSE TOWARDS THE W SIDE OF HUDSON
BAY WILL OPEN UP THE HYBRID POLAR/SRN STREAM TO ITS S AND SWEEP IT
RAPIDLY EWD INTO THE NWRN ATLANTIC. MEANWHILE ANOTHER IMPORTANT
SRN STREAM SYS SHOULD APPROACH CA AROUND TUE.

FINAL PROGS LEFT THE UPDATED PRELIM PROGS UNCHANGED. THE LATEST
UPDATED PRELIM PROG INCORPORATED THE 00Z/21 GFS INTO A 50-50
DETERMINISTIC GFS/ECMWF BLEND FOR DAYS 3-5. WE THEN TAPERED THAT
BLEND TO INCLUDE 50% OF THE 00Z/21 ECMWF ENSEMBLE MEAN FOR WED/THU
DAYS 6-7.

NEW 12Z/21 DETERMINISTIC MODELS APPEAR ON TARGET WITH OUR UPDATED
PRELIM CONTINUITY OVER THE CONUS THRU TUE DAY 5. THOUGH MODELS
DIFFER ON THE AMOUNT OF SSW DIGGING OF A CANADIAN POLAR VORTEX
EARLY NEXT WEEK...THEY AGREE ON A CLOSED BLOCKING 500MB HIGH
DEVELOPING UPSTREAM NEAR THE NE ALASKAN COAST AND ADJACENT CANADA.
THE CONFIGURATION OF THIS DEVELOPING BLOCKING HIGH/DIGGING VORTEX
IS SUCH THAT ALL DETERMINISTIC MODELS SHOW STRONG FLOW DROPPING E
OF THE UPPER HIGH INTO W CENTRAL CANADA BY MON/TUE. THIS
CONFIGURATION HELPS TO LOCK IN A COLD RIDGE OF ARCTIC HIGH PRES
FROM NE ALASKA SEWD INTO THE NRN PLAINS. THE GENERAL PATTERN
SHOULD SHOW CHUNKS OF SURFACE HIGH PRES PERIODICALLY BREAKING OFF
FROM THE MAIN SURFACE HIGH ASSOCIATED WITH THE BLOCKING HIGH
ALOFT. THESE BREAKOFF SURFACE HIGHS WILL MOVE SSE THRU WRN CANADA
INTO THE NRN PLAINS...THEN TURN ESE TOWARDS THE OH VLY. THIS WILL
HELP KEEP THE NE QUADRANT OF THE COUNTRY COLD.

THERE IS SOME DISAGREEMENT AMONG NEW 12Z/21 MODELS CONCERNING HOW
WELL THE NEW SYS APPROACHING THE W COAST OF THE CONUS BY EARLY TUE
HOLDS TOGETHER. THE CANADIAN MODEL KEEPS THE MOST ENERGY IN THE
NRN PORTION OF THE TROF AS IT APPROACHES THE PACIFIC NW...WHILE
SPLITTING OFF THE SRN PORTION OF THE TROF THE FARTHEST S NEAR
LATITUDE 25N. CONSENSUS OF THE NEW GFS/UKMET/ECMWF MODELS BRINGS
THE BULK OF THE UPPER ENERGY INTO THE W COAST AT A LATITUDE NEAR
OR JUST ABOVE 30N...A TRACK ALSO FAVORED BY THE ENSEMBLE SPAGHETTI
PLOTS. WE FAVOR CONTINUING THE ACTIVE SRN STREAM CONSENSUS.

ON ITS TREK EWD...THE CURRENT SYS BATTERING CA AND THE SWRN CONUS
WILL INDUCE STRONG FLOW FROM THE GULF OF MEXICO INTO THE ERN
QUARTER OF THE NATION SAT NIGHT INTO EARLY MON. MUCH ABOVE CLIMO
PRECIPITABLE WATER VALUES AHEAD OF THE ASSOCIATED FRONT COULD
BRING LOCALLY EXCESSIVE RAINFALL TO PORTIONS OF THE APPALACHIANS
WHICH HAVE HAD MORE THAN THEIR SHARE OF RAIN THE PAST FEW MONTHS.

STRONG RIDGING ALOFT WILL GIVE CA A BREAK FROM HEAVY WEATHER THIS
WEEKEND INTO MON...UNTIL THE NEW SRN STREAM SYS APPROACHES CA ON
TUE. WHILE RESPECTABLE...THIS NEW SHORTWAVE DOES NOT APPEAR TO
HAVE THE POWER OF THE CURRENT SERIES OF CA SYS. RIDGING AND DRIER
WEATHER WILL RETURN TO CA WED/THU IN THE WAKE OF THIS PASSING
SHORTWAVE.
FLOOD

[Ntxw]

Hints from today's FW AFD. Potential for a nice system, reminds me kind of like last weekend's storm but instead the nation would be in a colder pattern.

COOLER AIR WILL ARRIVE SUNDAY...WITH HIGHS ABOUT 10 DEGREES
COOLER THAN SATURDAY. NEXT WEATHER PRODUCER EXPECTED TO ARRIVE
THURSDAY...BUT WITH LITTLE CONTINUITY BETWEEN GFS AND EURO HAVE
CONTINUED TO STICK WITH THE EURO/S TIMING. HAVE LESS CONFIDENCE
IN GFS BECAUSE STRONG UPPER LOW EXPECTED OVER SOUTHERN CALIFORNIA
ON WEDNESDAY GETS RAPIDLY FILLED AND SHUNTED EAST BY THE GFS.
THESE STRONG UPPER LOWS HAVE NOT WEAKENED THAT FAST THIS WINTER.
EURO MAINTAINS THE SYSTEM...MOVING IT EAST SLOWER THAN THE GFS.

[txagwxman]

Looks like a surge of Arctic air may hit Texas next Thu/Fri...see what the newer runs do overnight. ECMWF kinda breaks it apart, while bringing an upper-level low from the west, but the GFS runs look more realistic and dive it down the Plains into Texas...

[Portastorm]

Larry Cosgrove talks about next weekend as well in a special update:

http://www.examiner.com/x-3775-Houston-Weather-Examiner~y2010m1d21-Special-WEATHERAmerica-Update-On-Storm-And-Pattern-Change-January-21-2010

[srainhoutx]

Overnight SSW/MMW data (Sudden Stratospheric Warming/Major Mid winter Warming) as well as some tropospheric warming all suggesting we are in fact heading back into a colder regime beginning as soon as late next week. For those into analogs, 1958 and 1973 continue to show up. While I believe that this cold spell will not be as sharp (as cold ) as we experienced earlier this month, we may see the month of February return to a colder than normal pattern as well as above normal percip chances. As we have heard repeatedly from wxman57 and others, February tends to bring our best chances of wintry weather to TX. I just hope it's not ice.

[jasons2k]

I certainly like the nice weather of this week compared to last week. I can go - and enjoy- outside again. As far as I'm concerned, the arctic air can stay bottled-up until next season. I've had enough for one year, thank you

[srainhoutx]

I certainly like the nice weather of this week compared to last week. I can go - and enjoy- outside again. As far as I'm concerned, the arctic air can stay bottled-up until next season. I've had enough for one year, thank you

Actually, me too Jason. The affects of the last event are really showing up now. Many folks are not aware of the amount of damage that has been done via frozen pipes as well as our tropicals. I did enjoy an evening by the pool last night, so the warmup has been rather pleasant. My yard has had enough for one year. ~Sigh~

[southerngale]

I like cold weather, and we've certainly had our fair share of it so far. This warm-up is nice... it feels absolutely fantastic outside!

I'd still like another winter wonderland, but the bitter cold can stay up north, where it belongs. My order is for cold enough to snow, and cold enough for it to stick around a few days.

[gboudx]

Hell may freeze over on February 7th. Imagine how cold it'll get if that happens.

[srainhoutx]

Just had time to check the 12Z GFS. Some of those -30+ temps at the 850mb height levels are concerning. The placement of the PV looks interesting as well. We'll see how the ECMWF handles the first feature next week. The GFS has been a touch too fast IMHO. There have been hints that a cutoff Upper Low will develop in the South West. As I mention in the When Will The Arctic Air Return thread, this pattern may persist a bit longer than many folks are expecting.

[Ntxw]

Again this resembles very much like the December\early January pattern only we are in mid to late winter which usually means colder.

[txagwxman]

I expect a very strong Arctic front to hit Texas next Friday...may see low 20s Dallas, upper 20s Houston next Saturday.
GFS, GFS ensembles more in-line with this now...so expect another hard freeze, but not a pipe buster.

Cheers.