Winter Storm and Winter Weather in Texas, March 27, 2009

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
624 AM CDT FRI MAR 27 2009

.AVIATION...
MAIN CONCERNS WILL BE THE NORTHWESTERLY WINDY CONDITIONS AND
FROZEN PRECIPITATION. POST FRONTAL NORTHERLY WINDS WILL REMAIN
GUSTY THROUGHOUT MOST OF THE DAY...WITH A SLIGHT DECREASE FOR THE
SUSTAINED WINDS AFTER SUNSET. IFR TO LIFR CLOUD DECKS THROUGHOUT
THE TAF PERIOD...WITH PRECIPITATION STARTING OFF AS RAIN THEN TURNING
OVER TO SNOW LATER THIS MORNING AT BOTH TAF SITES. AT THE VERY END
OF THE TAF PERIOD...KLBB COULD BEGIN TO SCATTER A BIT WITH VFR
CLOUD DECKS.

&&

.PREV DISCUSSION... /ISSUED 524 AM CDT FRI MAR 27 2009/

SHORT TERM...
AREA RADARS SHOWING PRECIPITATION EXPANDING ACROSS ERN NEW MEXICO
WHILE SATELLITE AND PROFILERS SHOWING CENTER OF UPPER LOW NEAR
ALBUQUERQUE MOVING SLOWLY SEWD. VORT MAX NEARING THE BASE OF THE
LOW ATTM AND WOULD THEN EXPECT MORE OF AN ESE TRAJECTORY. MODELS
HAVE REMAINED CONSISTENT WITH THEIR TRACK OF THE LOW AND
ASSOCIATED PRECIP GENERATION. GFS AND ECMWF REMAIN ABOUT 50 MILES
FURTHER SOUTH WITH THE LOW THAN DOES THE WRF-NAM AND HAVE
CONTINUED TO TREND THE FCST TOWARD THAT MORE SOUTHERLY SOLUTION.

PRECIP SHOULD SPREAD INTO THE WRN ZONES WITHIN THE NEXT SEVERAL
HOURS WITH SOME PERIOD CONVECTIVE PRECIP EWD ACROSS THE ERN HALF
OF THE FCST AREA IN AREA WHERE LOW LEVEL TEMPS SUPPORT RAIN. THIS
INITIAL BOUT OF PRECIP IS THE ONE MOST LIKELY TO AFFECT THE SRN
HALF OF THE FCST AREA DURING THE MORNING HOURS WITH A TRANSITION
IN THE AFTN FAVORING THE NRN HALF OF THE FCST AS A DEFORMATION
ZONE SETS UP ON THE NORTH SIDE OF THE UPPER LOW. THIS PROLONGED
PERIOD OF SNOW POTENTIAL CONTINUES TO WARRANT POSSIBITY OF 3-7
INCHES OF SNOW ACROSS THE WINTER STORM WARNING AREA. AREAS IN THE
ADVISORY AREA LESS LIKELY TO SEE PRECIPITATION THIS AFTN SOUTH OF
THE UPPER LOW UNLESS A LARGER WRAP-AROUND SHIELD DEVELOPS THAN
CURRENTLY ANTICIPATED. INDICATIONS ATTM SUGGEST PRECIP ACROSS MOST
OF THE ADVISORY AREA WILL END BY OR SHORTLY AFTER 00Z AND HAVE
ADJUSTED ENDING TIME ACCORDINGLY.

NORTH WINDS WILL ALSO BE A PROBLEM AS ADVISORY LEVEL WINDS WILL MIX
WITH THE MODERATE TO HEAVY SNOWFALL FURTHER REDUCING VISIBILITIES.
CONTEMPLATED A BLIZZARD WARNING FOR THE NORTHERN ROW OF THE FCST
AREA. CERTAINLY EXPECT TO SEE SOME 1/4 MILE VSBY ACROSS THOSE
PANHANDLE COUNTIES BUT AM UNCERTAIN WHETHER A DRAWN OUT 3 OR MORE
HOUR PERIOD OF THOSE EXTREMELY LOW VSBYS CAN BE REACHED. OPTED TO
JUST KEEP THE WINTER STORM WARNING AND WORD STRONGLY ATTM.

TEMPERATURES YET ANOTHER TRICKY PART OF THE FCST. AS OF 10Z ARCTIC
FRONT STRETCHED FROM BROWNFIELD TO SILVERTON WITH TEMPS DROPPING
QUICKLY BEHIND IT WHILE 40S AND 50S LINGERED EAST OF THE FRONT.
SHOULD SEE NEAR STEADY TEMPS FOR THOSE AREAS CURRENLY WEST OF THE
FRONT AND FALLING TEMPS EAST. THOSE WARMER TEMPS EAST HAVE
REQUIRED MENTION OF RAIN/SNOW MIX THERE THROUGH AT LEAST THE
MORNING HOURS.

DEFORMATION ZONE COULD CONTINUE TO PRODUCE SNOW ACROSS THE NERN
THIRD OF THE FCST AREA TONIGHT AND HAVE MAINTAINED HIGH POPS THERE
WHILE SWRN THIRD OF THE AREA LIKELY WILL SEE LITTLE IF ANY
ADDITIONAL PRECIP TONIGHT.

LONG TERM...
EXPECT SNOW TO BE EAST OF THE FCST AT THE BEGINNING OF THE DAY
SATURDAY. INCREASING LOW LEVEL TEMPS ARE EXPECTED AS HEIGHTS RISE
IN THE WAKE OF THE STORM SYSTEM. SNOW ON THE GROUND COULD VERY
WELL MODERATE THE WARMUP ACROSS THE NRN THIRD OR HALF OF THE FCST
AREA AND HAVE UNDERCUT GUIDANCE IN THAT AREA. OBVIOUSLY THIS PART
OF THE FCST CAN BE FINE TUNED ONCE FINAL SNOWFALL AMOUNTS AND AREA
ARE DETERMINED.

BEYOND SATURDAY VERY FEW CHANGES WERE MADE. MOST OF THE SHORT WAVE
ENERGY WILL STAY NORTH OF THE FCST AREA THROUGH NEXT WEEK.
EXCEPTION MAY BE THURSDAY WHEN AN OPEN TROUGH DIVES TOWARD THE SRN
PLAINS. CONFIDENCE IN A WET SOLUTION TOO LOW TO INSERT MENTIONABLE
POPS YET.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        26  19  49  29  69 / 100  60   0   0   0
TULIA         27  20  48  30  72 / 100  60   0   0   0
PLAINVIEW     28  24  50  30  73 /  90  30   0   0   0
LEVELLAND     31  25  56  33  79 /  70  10   0   0   0
LUBBOCK       32  26  54  33  76 /  70  10   0   0   0
DENVER CITY   36  26  60  34  78 /  40   0   0   0   0
BROWNFIELD    34  27  57  33  79 /  50  10   0   0   0
CHILDRESS     37  28  46  33  72 /  90  70  10   0   0
SPUR          39  29  51  32  74 /  50  10   0   0   0
ASPERMONT     44  31  51  34  77 /  40  10   0   0   0

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE
FOLLOWING ZONES: TXZ033>037-039>042.

WINTER WEATHER ADVISORY UNTIL 7 AM CDT SATURDAY FOR THE
FOLLOWING ZONES: TXZ031-032.

WINTER STORM WARNING UNTIL 7 AM CDT SATURDAY FOR THE FOLLOWING
ZONES: TXZ021>030.

&&

29

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LUBBOCK TX
529 AM CDT FRI MAR 27 2009

TXZ021>044-281030-
PARMER-CASTRO-SWISHER-BRISCOE-HALL-CHILDRESS-BAILEY-LAMB-HALE-
FLOYD-MOTLEY-COTTLE-COCHRAN-HOCKLEY-LUBBOCK-CROSBY-DICKENS-KING-
YOAKUM-TERRY-LYNN-GARZA-KENT-STONEWALL-
529 AM CDT FRI MAR 27 2009

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 WILL SPREAD ACROSS THE AREA TODAY WITH MODERATE TO
HEAVY SNOW EXPECTED ACROSS THE EXTREME SOUTHERN PANHANDLE AND
NORTHERN SOUTH PLAINS AND LIGHTER SNOWFALL AMOUNTS FURTHER SOUTH.
NORTH WINDS OF 25 TO 35 MPH WITH GUSTS TO 50 MPH WILL COMBINE WITH
SNOWFALL TO PRODUCE SIGNIFICANTLY REDUCED VISIBILITIES. A WINTER
STORM WARNING CONTINUES FOR ROUGHLY THE NORTHERN HALF OF THE AREA
WHILE A WINTER WEATHER ADVISORY CONTINUES FOR MUCH OF THE SOUTHERN
HALF.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

CRITICAL FIRE WEATHER CONDITIONS MAY BE POSSIBLE OVER MUCH OF THE
SOUTH PLAINS AREA SUNDAY AFTERNOON.