Texas Winter 2010-2011

[Ntxw]

Take a look at the AO and PNA. If it matches perfectly, what's coming up will have a big brother shortly after mid month.



I wonder if wxman is prepping up his underground bunker that constantly reads 90 degrees.

[orangeblood]

Looking over the 12Z GFS Ensembles, the 12-14th time range appears to have the best potential for a winter storm breaking out across central into north Texas. If a storm did materialize, it would have major impacts due to temps being below freezing for at least a couple of days before the event.

[DonWrk]

The easiest way to tell what temperatures are predicted is to go here:

http://wxweb.meteostar.com/sample/sampl ... ?text=kdfw

Portastorm, thanks for posting the discussion from Ft Worth, that's one of the most useful discos I've seen in a long time.

And to the someone who posted a while back that the historical Arctic outbreaks occur in waves that's not always the case. It was true in 1899, 1983 and 1989 but not so in 1962 or 1951.

Thanks, are these charts pretty accurate when looking at the temp? And I mean by looking at the temps on the chart of the website not the models.

[Ntxw]

Thanks, are these charts pretty accurate when looking at the temp? And I mean by looking at the temps on the chart of the website not the models.

The temps on the site comes directly from the GFS model data as is raw.

[WacoWx]

0 discussion in the last few hours????? c'mon guys/gals. Y'all got me all pumped up here and then everything just dropped off...on both threads. When does the next round of models come out? Any afternoon discos?

I cant add anything of substance as I cant read half of the models posted, but dang it if i dont like reading yalls theories on our impending doom!!!

Gonna start chanting here in a second:

G.F.S., G.F.S.,
G.F.S.

[DonWrk]

I'm in the same boat as you WacoWx, I've been refreshing for the past hour waiting to see some discussion!

[benrayrog]

Same here.

[Ivanhater]

We are in the "dead zone" in between model runs Nothing new until the next set with the 18z GFS coming up within the hour or so.

[bktkck]

000
FXUS64 KSHV 042027
AFDSHV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
227 PM CST TUE JAN 4 2011

MEDIUM RANGE PROGS CONTINUE TO SUPPORT A LARGE 1060MB POOL OF VERY
COLD...ARCTIC AIR SPILLING DOWN OUT OF THE NORTHERN PLAINS EARLY
NEXT WEEK WITH THE LEADING EDGE OF THIS AIRMASS MOVING INTO OUR
REGION DURING THE DAY MONDAY. DETAILS CONCERNING THE LONGEVITY AND
DEGREE OF COOLING THAT WILL TAKE PLACE IS STILL IN QUESTION BUT
WITHOUT A DOUBT...THIS WILL BE SOME OF THE COLDEST AIR OF THE
WINTER SEASON. ATTM...PREFER THE GFS HANDLING OF THE SFC RIDGING
ALONG THE FRONT RANGE AND KEEPING IT THERE THROUGHOUT NEXT WEEK AS
OPPOSED TO THE ECMWF WHICH PUSHES THE ARCTIC AIR TO FAR EAST TOO
QUICKLY. THIS IS SOMETHING THAT WILL BE WATCHED IN EARNEST
THROUGHOUT THE WEEK...BUT THIS AIRMASS AND UPPER LEVEL PATTERN
DOES MIMIC SOME OF THE MORE NOTABLE MCFARLAND SIGNATURES IN THE
PAST...INCLUDING DECEMBER OF 1983 AND DECEMBER OF 1989. HAVE MADE
MENTION OF THIS IN OUR HAZARDOUS WEATHER OUTLOOK...TALKING ABOUT
THIS AIRMASS NEXT WEEK ALONG WITH MAKING PREPARATIONS.

McFarland and 1983 and 1989 being mentioned. Get ready!

[HockeyTx82]

[youtube]http://www.youtube.com/watch?v=rq3qZKRtsd0[/youtube]

Will this hold you over?

[txtiff]

000
FXUS64 KSHV 042027
AFDSHV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
227 PM CST TUE JAN 4 2011

MEDIUM RANGE PROGS CONTINUE TO SUPPORT A LARGE 1060MB POOL OF VERY
COLD...ARCTIC AIR SPILLING DOWN OUT OF THE NORTHERN PLAINS EARLY
NEXT WEEK WITH THE LEADING EDGE OF THIS AIRMASS MOVING INTO OUR
REGION DURING THE DAY MONDAY. DETAILS CONCERNING THE LONGEVITY AND
DEGREE OF COOLING THAT WILL TAKE PLACE IS STILL IN QUESTION BUT
WITHOUT A DOUBT...THIS WILL BE SOME OF THE COLDEST AIR OF THE
WINTER SEASON. ATTM...PREFER THE GFS HANDLING OF THE SFC RIDGING
ALONG THE FRONT RANGE AND KEEPING IT THERE THROUGHOUT NEXT WEEK AS
OPPOSED TO THE ECMWF WHICH PUSHES THE ARCTIC AIR TO FAR EAST TOO
QUICKLY. THIS IS SOMETHING THAT WILL BE WATCHED IN EARNEST
THROUGHOUT THE WEEK...BUT THIS AIRMASS AND UPPER LEVEL PATTERN
DOES MIMIC SOME OF THE MORE NOTABLE MCFARLAND SIGNATURES IN THE
PAST...INCLUDING DECEMBER OF 1983 AND DECEMBER OF 1989. HAVE MADE
MENTION OF THIS IN OUR HAZARDOUS WEATHER OUTLOOK...TALKING ABOUT
THIS AIRMASS NEXT WEEK ALONG WITH MAKING PREPARATIONS.

McFarland and 1983 and 1989 being mentioned. Get ready!

Sorry if this seems like a dumb question. What is a McFarland???

[WacoWx]

We are in the "dead zone" in between model runs Nothing new until the next set with the 18z GFS coming up within the hour or so.

Thanks for the heads up!

[djmikey]

Houston newspaper blog about the upcoming event! Very interesting!

http://blogs.chron.com/sciguy/

[srainhoutx]

Sorry if this seems like a dumb question. What is a McFarland???

You can read all about the McFarland Signature here...

http://www.srh.noaa.gov/srh/ssd/techmemo/tm88.htm

[txtiff]

Sorry if this seems like a dumb question. What is a McFarland???

You can read all about the McFarland Signature here...

http://www.srh.noaa.gov/srh/ssd/techmemo/tm88.htm

Thank you!!

[Turtle]

Nice find djmikey!

On a sad note, my 7 day forecast is looking warm!

Sunday: A 30 percent chance of showers. Mostly cloudy, with a high near 66.
Sunday Night: Mostly cloudy, with a low around 39.
Monday: Mostly cloudy, with a high near 54.

Before it was highs in the 40s. Maybe the storm is coming in slower?

[WacoWx]

Fort Worth

000
FXUS64 KFWD 042142
AFDFWD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
342 PM CST TUE JAN 4 2011

.DISCUSSION...
CURRENT WATER VAPOR SATELLITE IMAGERY NICELY DEPICTS THE TWO SYSTEMS
WHICH WILL INFLUENCE NORTH TEXAS OVER THE NEXT FEW DAYS. THE
SHORTWAVE CURRENTLY MOVING THROUGH NORTHERN NEW MEXICO/SOUTHERN
COLORADO WILL MOVE THROUGH THE PLAINS EARLY TOMORROW MORNING. THIS
WILL FORCE SOME ADDITIONAL COLD AIR INTO NORTH TEXAS ALONG WITH A
SHIFT FROM LIGHT WESTERLY WINDS TO NORTHWESTERLY BY TOMORROW
AFTERNOON. THURSDAY AND FRIDAY SHOULD BE FAIRLY BENIGN AS THE AREA
REMAINS IN NORTHWESTERLY FLOW ALOFT AND THE STORM TRACK REMAINS
NEAR THE GREAT LAKES.

THE LOW PRESSURE SYSTEM WHICH IS CURRENTLY LOCATED
OFF THE SOUTHERN CALIFORNIA COAST IS PROGGED TO MOVE EAST ON
FRIDAY IN RESPONSE TO THE DEEPENING OF A LOW OVER THE PACIFIC
NORTHWEST. AS THE LOW IN THE NORTHWEST CONTINUES TO STRENGTHEN...THE
UPPER LEVEL DISTURBANCE OVER SOUTHERN CALIFORNIA QUICKLY
PROGRESSES EASTWARD MOVING INTO WEST TEXAS BY SATURDAY NIGHT.

THIS LOW CONTINUES PROGRESSING EASTWARD AND MOVES OVER NORTH TEXAS
SATURDAY EVENING. CLOUDS WILL BEGIN INCREASE EARLY SATURDAY IN
RESPONSE TO WEAK ISENTROPIC LIFT. THE ISENTROPIC ASCENT CONTINUES
TO INCREASE THROUGHOUT THE DAY SATURDAY AND WILL LIKELY RESULT IN
WIDESPREAD RAINFALL. THE GFS AND ECMWF DIFFER SIGNIFICANTLY ON THE
ON THE STRENGTH AND TRACK OF THE SYSTEM AS IT MOVES OVER
TEXAS...WITH THE ECMWF BEING STRONGER...FASTER...AND FARTHER
SOUTH. DESPITE THESE DIFFERENCES...THE OVERALL RESULT OF EACH OF
THE MODELS IS THE SAME FOR NORTH TEXAS. THAT RESULT IS RAIN
BEGINNING SATURDAY NIGHT AND CONTINUING UNTIL EARLY SUNDAY
MORNING. THE MORE SOUTHERLY TRACK PROGGED BY THE ECMWF ALLOWS THE
LOW TO INTENSIFY MORE...WHICH RESULTS IN THE DEVELOPMENT OF SOME
WRAP AROUND PRECIP. IF THIS VERIFIES LIGHT RAINFALL COULD CONTINUE
THROUGH THE LATE MORNING SUNDAY. STRONG LIFT AND MODERATE LAPSE
RATES INDICATE THUNDER IS POSSIBLE BUT THE THREAT WILL REMAIN
ISOLATED.

THIS LOW WILL CONTINUE TO PUSH EAST ON SUNDAY WHILE ANOTHER LOW
PRESSURE SYSTEM...THE ONE THAT WAS LOCATED IN THE PACIFIC
NORTHWEST ON FRIDAY...MOVES OVER THE NORTHERN PLAINS AND SENDS A
STRONG COLD FRONT THROUGH NORTH TEXAS MONDAY MORNING. THIS COLD
RESULTS FROM THE PATTERN SHIFT MANY PREVIOUS DISCUSSIONS HAVE
MENTIONED AND WILL BE THE BEGINNING OF A SIGNIFICANT COLD SPELL
FOR TEXAS.

42/MM

&&

.EXTENDED/COLD WX NEXT WEEK...
CONFIDENCE REMAINS HIGH THAT MUCH OF THE CONTINENTAL US WILL SEE
TEMPERATURES WELL BELOW NORMAL FOR MUCH OF NEXT WEEK AND THERE
HAS BEEN MUCH DISCUSSION AS TO WHETHER OR NOT IT WILL GET AS COLD AS
SOME OF THE MORE SEVERE ARCTIC INTRUSIONS OF YEARS PAST. LATEST
GLOBAL MODEL GUIDANCE CONTINUES TO SHOW EXPECTED OSCILLATIONS WITHIN
THE OVERALL UPPER AIR PATTERN BUT THE GENERAL CONSENSUS IS THAT
RIDGING OVER ALASKA WILL BUILD SUFFICIENTLY STRONG AND BECOME
PARTIALLY BLOCKED AS TO ALLOW A MASSIVE CHUNK OF COLD AIR TO HEAD
SOUTH INTO THE CONTINENTAL US. THE FIRST SHOT OF THIS COLD AIR WILL
MOVE RAPIDLY INTO NORTH TEXAS EARLY MONDAY WITH STRONG NORTHERLY
WINDS AND SHARPLY COLDER TEMPERATURES. AS WE HEAD THROUGH NEXT WEEK
HOWEVER...THERE ARE SOME CONCERNS AS TO WHETHER THE OVERALL PATTERN
WILL REMAIN FAVORABLE FOR CONTINUED SURGES OF COLD AIR.

EXTENSIVE ANALYSIS OF ARCHIVED UPPER AIR DATA FROM PREVIOUS RECORD
BREAKING COLD EVENTS INCLUDING THE SEVERE COLD SNAPS OF 1983 AND
1989 YIELD A COUPLE OF INTERESTING DETAILS. THE MOST SIGNIFICANT
ARE THE TEMPERATURES AT THE SOURCE OF BITTERLY COLD AIR.
GENERALLY... ARCTIC INTRUSIONS INTO NORTH TEXAS BEGIN WITH EXTREMELY
COLD AIR PARCELS WITHIN THE 800 TO 500MB LAYER LOCATED OVER
NORTHWEST/ NORTH-CENTRAL CANADA. THESE PARCELS WILL GRADUALLY
SUBSIDE AND WARM AS THEY HEAD SOUTH BUT ARE USUALLY STILL VERY COLD
BY THE TIME THEY REACH THE SURFACE. IN AT LEAST A HALF-DOZEN MAJOR
COLD SNAPS INCLUDING 1983/1989/1996...THE 500MB TEMPS ACROSS
NORTHWEST CANADA WERE TYPICALLY IN THE -45 TO -50C RANGE...AND 700MB
TEMPS WERE TYPICALLY IN THE -30 TO -35C RANGE. THE RECORD COLD OF
1983 HAD A SAMPLED 500MB TEMP OF -50C IN NORTHERN MONTANA. AS OF
NOW...NEITHER THE GFS NOR THE ECMWF HAS TEMPERATURES THAT COLD
ACROSS CANADA. PROGGED 850MB TEMPS ACROSS NORTH TEXAS ARE IN THE
-10 TO -15C RANGE WHICH DEFINITELY SUPPORTS COLD TEMPERATURES AT THE
SURFACE...HOWEVER IN THE EXTREME EVENTS...H85 TEMPS WERE IN THE -17
TO -20C RANGE WITH A FRIGID -24C AT OKC IN 1983. GIVEN THE FORECAST
TEMPERATURES THROUGH NEXT WEEK...CONFIDENCE IS INCREASING THAT THIS
WILL NOT BE HISTORICALLY COLD ACROSS NORTH TEXAS. OF COURSE THIS
ASSUMES A PERFECT PROG OF THE MODEL TEMPERATURES. THE OTHER CONCERN
IS THE POSITION OF THE UPPER RIDGE OVER ALASKA. THE LATEST RUNS
CONTINUE TO BUILD AN ANOMALOUSLY STRONG RIDGE OVER AK THEN HAVE HAD
SOME TROUBLE AS TO WHETHER IS WILL MOVE NORTH OR WEST INTO SIBERIA.
THIS RIDGE POSITION HAS IMPLICATIONS ON THE UPPER PATTERN OVER THE
WESTERN US. TYPICALLY WE LIKE TO SEE A STRONG TROF POSITIONED OVER
THE WEST/SW US WHICH DOES NOT MOVE TO KEEP THE COLD AIR FLOWING
SOUTHWARD. THESE MODEL DISCREPANCIES ARE EXPECTED IN THE 10-15 DAY
PERIOD AND WILL CONTINUE TO BE MONITORED.

AS OF NOW WE WILL CONTINUE TO SHOW THE STRONG FRONT ON MONDAY/END OF
THE CURRENT FORECAST PERIOD/ AND WILL INTRODUCE HIGH TEMPERATURES IN
THE UPPER 20S/LOWER 30S FOR TUESDAY THROUGH THE END OF NEXT WEEK.
OVERNIGHT LOWS WILL GENERALLY BE IN THE LOWER TEENS AND LOWER 20S.
IT SHOULD BE STRESSED THAT CONSIDERABLE DISCREPANCIES WITHIN THE
FINER DETAILS EXIST THIS FAR OUT AMONG NOT ONLY THE OPERATIONAL
GUIDANCE BUT AMONG THE INDIVIDUAL ENSEMBLE MEMBERS. SEVERAL
ENSEMBLE MEMBERS TO INDICATE A FAVORABLE RIDGE/TROF POSITION THROUGH
NEXT WEEK AND KEEP THE COLD AIR COMING SO IT WILL BE NECESSARY TO
FINE TUNE TEMPERATURE FORECASTS THROUGH NEXT WEEK. WHAT MAKES THIS
SYSTEM SIGNIFICANT IS THE POTENTIAL FOR THERE TO BE AN EXTENDED
PERIOD OF VERY COLD TEMPERATURES ACROSS THE REGION. IT IS THE
DURATION OF SUB-FREEZING AIR THAT CAN HAVE SERIOUS IMPACTS TO THE
REGION VERSUS JUST THE TEMPERATURES THEMSELVES.

CONCERNING PRECIPITATION POTENTIAL...LATEST 12Z ECMWF DOES SHOW AN
AREA OF QPF ALONG THE FRONT ON MONDAY LIKELY IN AN AREA OF STRONG
FRONTOGENETIC FORCING SQUEEZING OUT ANY AVAILABLE MOISTURE. TEMPS
ARE SUFFICIENTLY COLD FOR SNOW...BUT IT IS THE ONLY MODEL DOING SO
WITH SUCH VIGOR ATTM. BEING 7 DAYS OUT...WILL LEAVE THE 10 POPS IN
AND SEE IF THIS TREND CONTINUES. INTO NEXT WEEK...WITH TEMPS SO
COLD ANY MOISTURE COULD CREATE WINTRY PRECIPITATION BUT AS OF NOW IT
APPEARS THAT THINGS WILL BE VERY DRY. THESE DETAILS WILL BE WORKED
OUT OVER THE NEXT SEVERAL DAYS.

DUNN

[Ntxw]

Seems the NWS are biting into the impending cold. Rare to see them focus in on something like this a week in advance especially with specific possible temps. Looks like the wheels are in motion.

HGX

EARLY
NEXT WEEK A LARGE UPPER TROUGH/LOW WILL MOVE OVER THE GREAT BASIN
AND PULL ALONG THE MODIFIED AR ARCTIC AIR MASS SITTING OVER WESTERN
CANADA. WE SHOULD START TO SEE SIGNIFICANTLY COLDER AIR MASS
FILTERING INTO OUR REGION MONDAY NIGHT WITH STRONG COLD AIR
ADVECTION CONTINUING FOR SEVERAL DAYS. MORE ON THIS LATER. 37

[DonWrk]

Much change in the newest released models?

[Ntxw]

Much change in the newest released models?

18z finishes in about 30 mins, hang in there