Winter Storm and Extreme Cold in Texas, February 8 to 9, 2011

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
324 PM CST TUE FEB 8 2011

.SHORT TERM...
ANOTHER STRONG COLD FRONT BISECTS THE AREA...SNOW ONCE AGAIN ON THE
WAY.

20Z SURFACE ANALYSIS INDICATES COLD FRONT HAS SAGGED ACROSS THE
SOUTH PLAINS TO A HOBBS...SEMINOLE...TAHOKA...FLOYDADA... TO
CLARENDON LINE.  SOUTH AND EASTWARD PROGRESS HAS SLOWED CONSIDERABLY
COMPARED TO THIS MORNING AS DAYTIME MIXING SOUTH OF THE FRONT HAS
PEAKED AND BROUGHT THE FRONT TO A CRAWL.  QUITE A TEMPERATURES
CONTRAST EXISTS AS WELL...RANGING FROM 9 DEGREES AT FRIONA TO 62
DEGREES AT THE LAKE ALAN HENRY WEST TEXAS MESONET SITES.

ALOFT...12Z UPA HAND ANALYSIS SHOWED MAIN TROF AXIS AT 500HPA WAS
LOCATED FROM SRN CALIFORNIA INTO NE WY/SW MT AND WV SATELLITE LOOP
SHOWS THE TROF STARTING TO MOVE TOWARDS THE REGION. STRONGEST
PART OF THIS STORM SYSTEM SHOWED UP ON THE 700HPA CHART AS A
CLOSED LOW OVER THE UT/CO/WY BORDER REGION. 250HPA CHART SHOWS A
STRONG JET WAS DIVING OVER THE NW PACIFIC COAST. DEPENDING ON
WHERE THESE FEATURES MOVE OVER THE REGION WILL HAVE AN IMPACT ON
HOW MUCH SNOW WE WILL SEE AND FOR HOW LONG.

ALTHOUGH FLURRIES AND BLOWING SNOW HAVE BEEN REPORTED IN THE
PANHANDLE AND AS FAR SOUTHWEST AS CLOVIS...EXPECT TO SEE HEAVIER
SNOW DEVELOP LATER TONIGHT AS THE MAIN TROF AXIS MOVES TOWARDS THE
REGION.  NAM IS ALSO DEPICTING AN AREA OF GOOD FRONTOGENETICAL
FORCING BECOMING MAXIMIZED OVER THE FORECAST AREA FROM 850 TO 750
HPA BY 06Z/MIDNIGHT WEDNESDAY AS WELL WHILE THE GFS IS MUCH NARROWER
WITH IT/S DEPICTION OF THIS FIELD.  500-300 Q-VECTOR LAYERS ALSO
INDICATE THAT LARGE-SCALE LIFT WILL ALSO BE MAXIMIZED OVER THE
EASTERN FORECAST AREA INTO OKLAHOMA ABOUT THIS TIME FRAME AS
WELL...HOWEVER MODEL AND BUFKIT SOUNDINGS SHOW THAT LIFT IN THE
DENDRITIC GROWTH ZONE WILL BE RATHER ANEMIC.  MODELS CONTINUE TO
PAINT THE HEAVIEST QPF AND THUS SNOWFALL OVER THE NORTHEASTERN
ROLLING PLAINS AND FAR SOUTHEASTERN TEXAS PANHANDLE...CARRYING INTO
OKLAHOMA.  THEREFORE THE MAIN CONCERNS FOR SNOWFALL AMOUNTS WILL BE
DUE TO THE SNOW/WATER RATIO AND EXACTLY WHERE MESOSCALE FEATURES AND
BANDS WILL SET UP.

COMPARING SNOWFALL FORECAST WITH A DRIER 20 TO 1 SNOW RATIO ON THE
IOWA STATE BUFKIT WAREHOUSE FOR SITES AROUND THE FORECAST AREA SHOW
DECENT RUN-TO-RUN CONSISTENCY IN THE RANGE OF SNOWFALL TOTALS ACROSS
THE AREA.  CONTINUED THE PREVIOUS THINKING OF 4-6 INCHES POSSIBLE
ACROSS THE NORTHEASTERN ROLLING PLAINS WITH 1-3 INCHES ACROSS A
SWATH FROM FRIONA TO ASPERMONT AND INCLUDING LUBBOCK.  UP TO 1 INCH
MAY DEVELOP OVER THE FAR SOUTHWESTERN SOUTH PLAINS.  CURRENT WINTER
STORM WARNING AND WINTER WEATHER ADVISORIES LOOK TO BE IN GOOD SHAPE
AND WILL CONTINUE AS IS.  STILL EXPECT TO SEE SOME PERIODS OF NEAR
WHITEOUT CONDITIONS AS THE MAIN PUSH BEHIND THE FRONT MOVES ACROSS
THE REST OF THE REGION TONIGHT AND AS THE PERIOD OF HEAVIEST SNOW
OCCURS.  VERY COLD WIND CHILLS ALSO WILL REMAIN A CONCERN OVERNIGHT
AND HAVE HIGHLIGHTED THIS IN THE ROUTINE SUITE OF PRODUCTS.

EXPECT TO SEE SNOW TAPER OFF FROM WEST TO EAST TOMORROW
MORNING...COMING TO AN END ACROSS THE ROLLING PLAINS BY TOMORROW
AFTERNOON.  SKIES MAY MANAGE TO CLEAR AS WELL FROM WEST TO EAST
WHICH WILL MAKE FOR A DIFFICULT HIGH TEMPERATURE FORECAST FOR
TOMORROW....BUT EXPECT ALL AREAS TO REMAIN BELOW FREEZING THROUGH
THE DAY WITH THE SURFACE RIDGE PARKED OVER THE REGION.

JORDAN

&&

.LONG TERM...
MAIN CONCERN FOR THIS FORECAST PACKAGE WILL BE THE WINTER STORM THAT
WILL IMPACT THE SOUTH PLAINS TONIGHT AS MENTIONED PER THE SHORT TERM
DISCUSSION...WITH A NOTABLE DECLINE IN PRECIP AT THE START OF THE
LONG TERM FORECAST.

THE UA TROUGH/WINTER STORM IS PROGGED TO TRANSLATE ESE ACROSS THE
SOUTHERN PLAINS THROUGH WEDNESDAY. MEDIUM TO LONG RANGE SOLUTIONS
DISPLAYED THE BEST SYNOPTIC LIFT AND HENCE BEST PRECIP CHANCES TO
SHIFT WELL EAST OF THE SOUTH PLAINS BY WEDNESDAY EVENING/NIGHT.
HENCE OVERCAST SKIES WILL GIVE WAY TO CLEARING SKIES FROM WEST TO
EAST. AS A RESULT...HAVE KEPT BELOW MENTIONABLE POPS WEDNESDAY
NIGHT. NORTHERLY SFC WIND SPEEDS AOA 10 KTS WILL BE LEFT IN ITS
WAKE BUT WILL BACK TO THE WEST SOUTHWEST AND BECOME LIGHT EARLY
THURSDAY MORNING...THANKS TO A SFC RIDGE EAST OF THE CWFA.
THUS...WITH ANTICIPATED SNOW ON THE GROUND...LIGHT WINDS AND
GENERALLY CLEAR SKIES...THURSDAY MORNING WILL BE QUITE COLD WITH
EXPECTED TEMPS RANGING FROM 1 TO 8 DEGREES. FURTHERMORE...WIND
CHILLS RANGING FROM -5 TO -11 DEGREES ACROSS THE SOUTH PLAINS WILL
OCCUR...WHICH IS JUST SHY OF WIND CHILL ADVISORY CRITERIA ATTM /-5
TO -14 DEGREES AND WIND SPEEDS 8 KTS OR GREATER/.

THEREAFTER...ANOTHER UA IMPULSE WILL PROPAGATE EAST ACROSS THE REGION
ON THURSDAY...BUT LACK OF SYNOPTIC LIFT WILL INDUCE SILENT POPS. UA
RIDGING ACROSS THE WESTERN CONUS WILL COMMENCE BY FRIDAY...AND
SLOWLY DE-AMPLIFY AND SHIFT EAST ACROSS THE SOUTHERN PLAINS
THROUGHOUT THE WEEKEND. CONCURRENTLY...SFC WINDS WILL SHIFT TO A
WEST TO SOUTHWESTERLY COMPONENT BY SATURDAY...AND BECOME SLIGHTLY
BREEZY BOTH SATURDAY AND SUNDAY AFTERNOON. WITH FORECAST SOLUTIONS
SHOWING INCREASING MID TO UPPER LEVEL THICKNESS VALUES...TEMPS WILL
WARM INTO THE LOWER TO MID 60S /AND PERHAPS A FEW UPPER 60S ACROSS
SOUTHERN ZONES/ BY SUNDAY. BY LATE SUNDAY AFTERNOON/EVENING...NEAR
ZONAL FLOW ALOFT WILL PREVAIL AS THE GFS SOLUTION SHOWED A DRY
NORTHERLY FROPA MOVING ACROSS THE CWA. THE ECMWF SOLUTION WAS A BIT
SLOWER WITH THE FROPA AS IT SHOWED A MONDAY MORNING TIME-FRAME. IN
EITHER CASE...HAVE MAINTAINED LOWER TEMPS ON MONDAY /MID TO UPPER
50S/. UA RIDING WILL ONCE AGAIN OCCUR ACROSS THE WESTERN CONUS AT
THE BEGINNING OF NEXT WEEK AS SOUTHERLY SFC WINDS PREVAIL.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA         1  17   1  34  14 / 100  20  10   0   0
TULIA          4  20   2  34  15 / 100  40  10   0   0
PLAINVIEW      5  20   3  34  18 /  90  40  10   0   0
LEVELLAND      7  23   6  39  14 /  60  20   0   0   0
LUBBOCK        9  22   5  36  15 /  70  40   0   0   0
DENVER CITY   11  28   6  42  17 /  50  20   0   0   0
BROWNFIELD    11  25   6  41  18 /  60  20   0   0   0
CHILDRESS      8  19   3  33  18 / 100  50  10   0   0
SPUR          11  23   6  38  16 /  70  50  10   0   0
ASPERMONT     13  22   7  35  17 /  70  60  10   0   0

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON CST
WEDNESDAY FOR THE FOLLOWING ZONES: TXZ021>023-027>030-033>044.

WINTER STORM WARNING FROM 6 PM THIS EVENING TO NOON CST
WEDNESDAY FOR THE FOLLOWING ZONES: TXZ024>026-031-032.

&&

14/29

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LUBBOCK TX
1109 AM CST TUE FEB 8 2011

TXZ021>044-091715-
PARMER-CASTRO-SWISHER-BRISCOE-HALL-CHILDRESS-BAILEY-LAMB-HALE-
FLOYD-MOTLEY-COTTLE-COCHRAN-HOCKLEY-LUBBOCK-CROSBY-DICKENS-KING-
YOAKUM-TERRY-LYNN-GARZA-KENT-STONEWALL-
1109 AM CST TUE FEB 8 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE EXTREME SOUTHERN TEXAS
PANHANDLE...SOUTH PLAINS AND ROLLING PLAINS.

.DAY ONE...TODAY AND TONIGHT

WINTER WEATHER

A WINTER STORM WARNING IS IN EFFECT FOR THE EXTREME SOUTHEASTERN
PANHANDLE AND NORTHERN ROLLING PLAINS FROM 6 PM THIS EVENING THROUGH
NOON CST WEDNESDAY. WINTER WEATHER ADVISORY IN EFFECT FOR THE
EXTREME SOUTHWESTERN PANHANDLE...SOUTH PLAINS...AND LOWER ROLLING
PLAINS FROM 6 PM THIS EVENING TO NOON CST WEDNESDAY.

A STRONG COLD FRONT WILL MOVE THROUGH THE SOUTH PLAINS REGION THIS
AFTERNOON...BRINGING A CHANCE FOR SNOWFALL ACCUMULATIONS TONIGHT
INTO WEDNESDAY. GENERALLY...BETWEEN ONE TO THREE INCHES OF
SNOWFALL IS EXPECTED ACROSS MOST OF THE AREA...BUT LOCALLY HEAVIER
AMOUNTS OVER FOUR INCHES WILL BE POSSIBLE ACROSS THE EXTREME
SOUTHEASTERN PANHANDLE AND NORTHERN ROLLING PLAINS. IN ADDITION TO
THE SNOWFALL POTENTIAL...BITTERLY COLD TEMPERATURES AND STRONG
NORTHERLY WINDS WILL COMBINE TO RESULT IN WIND CHILL VALUES
BETWEEN MINUS FIVE AND MINUS FIFTEEN DEGREES AFTER MIDNIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THE COMBINATION OF BITTERLY COLD TEMPERATURES AND BREEZY NORTHERLY
WINDS WILL CREATE LOW WIND CHILL VALUES BETWEEN ZERO AND MINUS
FIFTEEN DEGREES WEDNESDAY MORNING AND AGAIN WEDNESDAY NIGHT INTO
THURSDAY MORNING.

.SPOTTER INFORMATION STATEMENT...
EMERGENCY MANAGEMENT AND FIRST RESPONDER AGENCIES ARE URGED TO RELAY
REPORTS OF WINTER WEATHER AND ITS IMPACTS TO THE NATIONAL WEATHER
SERVICE IN LUBBOCK.