Frost Advisory 5, NWS Amarillo, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO TX
700 PM CDT THU OCT 24 2013

.AVIATION...DISCUSSION FOR 00Z TAFS

VFR CONDITIONS SHOULD PREVAIL. THERE IS A VERY SLIGHT CHANCE THAT A
FEW LOW CLOUDS COULD DEVELOP AROUND 2KFT FROM ROUGHLY 10Z-15Z...BUT
THE CHANCE IS LOW ENOUGH TO PRECLUDE INCLUSION IN THE TAFS.

THERE IS ALSO A VERY SLIGHT CHANCE FOR A RAIN SHOWER DURING THE DAY
ON FRIDAY...BUT AGAIN THE CHANCE IS TOO LOW TO INCLUDE. WINDS WILL
VEER FROM SE TO SSW BY THE END OF THE PERIOD.

SIMPSON
&&

.PREV DISCUSSION... /ISSUED 325 PM CDT THU OCT 24 2013/

DISCUSSION...
SURFACE HIGH PRESSURE WILL MOVE OFF TO THE EAST OF THE PANHANDLES
TONIGHT. SOUTHEAST SURFACE WINDS WILL BECOME SOUTH TO SOUTHWEST AND
GUSTY ON FRIDAY IN RESPONSE TO A DEEPENING SURFACE LOW OVER EASTERN
COLORADO. STILL DO NOT EXPECT MUCH IN THE WAY OF MOISTURE ADVECTION
AHEAD OF AN UPPER LEVEL SHORT WAVE TROUGH MOVING THIS DIRECTION
FROM THE SOUTHERN ROCKIES ON FRIDAY. STILL THINK THAT THIS SYSTEM
WILL STILL HAVE ENOUGH LIFT WITH IT TO PRODUCE SOME SHOWERS FRIDAY
AFTERNOON INTO SATURDAY ACROSS THE AREA...WITH THE BEST CHANCES
ACROSS THE SOUTHERN TEXAS PANHANDLE. A THUNDERSTORM OR TWO WILL ALSO
BE POSSIBLE ON SATURDAY AS A COLD FRONT MOVES SOUTH AND PROVIDES SOME
EXTRA LIFT ALONG WITH THE UNSTABLE ATMOSPHERE UNDER THE SHORT WAVE
TROUGH MOVING ACROSS.

TEMPERATURES WILL WARM BACK UP AGAIN ABOVE NORMAL BY SUNDAY AS A LEE-
SIDE SURFACE TROUGH ENCOURAGES DOWNSLOPE WINDS.

AFTER MONDAY...THE MODELS DO NOT AGREE. THE GFS IS THE MOST
PROGRESSIVE WITH THE UPPER TROUGH OVER THE WESTERN U.S. THE CMC
MODEL IS JUST ABOUT AS FAST AS THE GFS BUT IT SWINGS THE UPPER
TROUGH MUCH FURTHER TO THE NORTH. THE ECMWF IS THE SLOWEST OF THE
MODELS. THE ECMWF MODEL IS THE PREFERRED MODEL TODAY. BUT CHECK BACK
TOMORROW...BECAUSE IT COULD BE ANOTHER MODEL. WE ARE LEANING TOWARD
THE ECMWF MODEL BECAUSE IT LOOKS LIKE THE RIDGE OFF OF THE WEST
COAST WILL AMPLIFY QUITE A LITTLE. IN TURN THE UPPER TROUGH SHOULD
DIG SOUTHWARD ON THE FRONT SIDE OF THIS RIDGE THROUGH CALIFORNIA
BEFORE IT LIFTS OUT TO THE EAST AND NORTHEAST. THE PROBLEM IS THAT
THE UPPER LEVEL LOW MAY EVEN DIG FURTHER SOUTH THAN THE CURRENT
ECMWF AND IT MAY TAKE LONGER TO LIFT OUT. THEREFORE...HAVE
CONTINUED TO LEAVE POPS OUT OF THE FORECAST.

WHILE THE UPPER LEVEL TROUGH IS DIGGING SOUTHWARD ACROSS THE WESTERN
U.S. A BACKDOOR COLD FRONT MAY TRY TO MOVE INTO THE PANHANDLES AS
EARLY AS TUESDAY. THIS FRONT MAY THEN MOVE BACK AND FORTH ACROSS
OUR AREA UNTIL THURSDAY. THERE IS SOME INDICATION THAT THERE COULD
BE COOL CONDITIONS WITH LOW CLOUDS AND DRIZZLE BEHIND THIS COLD FRONT
WITH SUNNY AND WARM CONDITIONS AHEAD OF IT. THE BIG QUESTION WILL
BE JUST HOW SHALLOW THE FRONT WILL BE AND WILL IT LIFT NORTH OUT OF
THE CWA EACH DAY OR NOT. FOR NOW HAVE GONE TOWARD THE WARMER
SOLUTION...THINKING THAT THE AIR MASS WILL BE VERY SHALLOW AND EASY
TO ERODE UNDER THE OCTOBER SUNSHINE.

FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
THROUGH THE WEEKEND INTO EARLY NEXT WEEK. SOME SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE FRIDAY AND SATURDAY AND THEN
THE 20 FOOT WINDS WILL BE LESS THAN 20 MPH WITH LOWEST
RELATIVE HUMIDITY VALUES LESS THAN 20 PERCENT ACROSS THE
WESTERN PANHANDLES ON MONDAY.

&&

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

&&

09/16

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE AMARILLO TX
838 PM CDT THU OCT 24 2013

OKZ001>003-TXZ001>020-251100-
CIMARRON-TEXAS-BEAVER-DALLAM-SHERMAN-HANSFORD-OCHILTREE-LIPSCOMB-
HARTLEY-MOORE-HUTCHINSON-ROBERTS-HEMPHILL-OLDHAM-POTTER-CARSON-
GRAY-WHEELER-DEAF SMITH-RANDALL-ARMSTRONG-DONLEY-COLLINGSWORTH-
838 PM CDT THU OCT 24 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE TEXAS AND OKLAHOMA
PANHANDLES.

.DAY ONE...TONIGHT.

VERY COLD WEATHER IS EXPECTED TONIGHT OVER THE EASTERN AND CENTRAL
PANHANDLES. TEMPERATURES AT OR BELOW FREEZING ARE EXPECTED FOR MUCH
OF THIS AREA...WHERE A FREEZE WARNING HAS BEEN ISSUED. IN
COLLINGSWORTH COUNTY...TEMPERATURES JUST ABOVE FREEZING ARE EXPECTED
THOUGH FROST IS STILL POSSIBLE...THUS A FROST ADVISORY HAS BEEN
ISSUED.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

THE FREEZE WARNING AND FROST ADVISORY CONTINUES THROUGH 10 AM
TOMORROW MORNING.

ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS THE SOUTHEAST HALF OF
THE TEXAS PANHANDLE ON SATURDAY. NO STRONG OR SEVERE STORMS ARE
EXPECTED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME.

JOHNSON/GOEHRING