000
FXUS64 KAMA 131614
AFDAMA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO TX
1114 AM CDT MON MAY 13 2013

.UPDATE...

QUICK UPDATE TO RAISE HIGH TEMPERATURES A FEW DEGREES FOR THIS
AFTERNOON. NEARLY FULL SUNSHINE, DOWNSLOPING WINDS, AND INCREASING
H85 TEMPS SHOULD ALLOW THE MAJORITY OF THE PANHANDLES TO FLIRT WITH
OR CROSS 90 DEGREES. THE OKLAHOMA PANHANDLE WILL BE THE WARMEST AREA
AS THEY ARE CLOSER TO THE SOUTHEAST EDGE OF A STRONG UPR RIDGE.
HIGHS IN THE OK PANHANDLE WILL LIKELY PUSH INTO THE MID TO UPR 90S
THIS AFTERNOON...WHICH WILL ONLY BE ABOUT ANOTHER 10-12 DEGREES FROM
THE BALMY 11 AM TEMP OF 84 DEGREES AT GUYMON.

SIMPSON
&&

.PREV DISCUSSION... /ISSUED 618 AM CDT MON MAY 13 2013/

AVIATION...
GENERALLY CLEAR SKY IS FORECAST FOR NEXT 24 HOURS...WITH CIRRUS BEING
THE ONLY CLOUDS OF NOTE.  LOW-LEVEL JET CURRENTLY DETECTED BY KAMA
88D VELOCITY DATA AND VAD WIND PROFILE WITH 35 TO 55 KT SOUTHWEST
WINDS INDICATED WITHIN 1500 FEET OF SURFACE.  EXPECT SOME GUSTINESS
OF SURFACE WINDS TO AROUND 25 KT FOR MUCH OF THIS MORNING AROUND KAMA
AS THESE STRONGER WINDS MIX TO THE SURFACE.  LIGHTER SURFACE WINDS
EXPECTED THIS AFTERNOON AS ZONE OF STRONGER WINDS DEPARTS AND DEEP
MIXING TAPS WEAKER FLOW.  GENERALLY SOUTHWEST DIRECTION ANTICIPATED
FOR ALL TERMINALS FOR THIS FORECAST.  NO VISIBILITY RESTRICTIONS
EXPECTED.  VFR FORECAST CONTINUES NEXT 24 HOURS.

COCKRELL

PREV DISCUSSION... /ISSUED 456 AM CDT MON MAY 13 2013/

DISCUSSION...
A WARM TO AT TIMES HOT WEEK IS AHEAD FOR THE PANHANDLES. THE MAIN
FORECAST CHALLENGE LIES WITH THUNDERSTORM CHANCES...WHICH OVERALL
WILL BE LOW AND MAINLY CONFINED TO THE EASTERN PANHANDLES.

A NORTHWEST FLOW ALOFT REMAINED IN PLACE ACROSS THE PANHANDLES THIS
MORNING...IN BETWEEN AN UPPER RIDGE OVER THE INTERMOUNTAIN WEST AND
AN UPPER TROUGH ACROSS THE EASTERN CONUS. A CUTOFF UPPER LOW
CONTINUES TO SPIN OVER NORTHERN MEXICO EARLY THIS MORNING. A
SOUTHWEST BREEZE OVERNIGHT HAS KEPT TEMPS MILD...WITH 4 AM READINGS
IN THE LOWER 50S TO LOWER 60S.

DRY AND WARM CONDITIONS WILL PREVAIL TODAY. HEIGHTS WILL RISE AS THE
WESTERN UPPER RIDGE SLOWLY PROPAGATES EASTWARD...WHILE SOUTHWEST
SURFACE WINDS PERSIST WITHIN A BROAD SURFACE TROUGH DRAPED ACROSS THE
PLAINS STATES. WINDS WILL BECOME BREEZY FOR A PERIOD THIS MORNING AS
A 40 KT NOCTURNAL LLJ MIXES OUT...BUT THEN DECREASE TO AROUND 15 MPH
OR LESS FOR THE AFTERNOON.

THE FLOW ALOFT WILL DEAMPLIFY ON TUESDAY AS THE EASTERN TROUGH MOVES
OFFSHORE AND THE WESTERN RIDGE IS FLATTENED BY A SHORTWAVE RIDING
ACROSS SOUTHERN CANADA/THE NORTHERN TIER STATES. THE CUTOFF LOW OVER
MEXICO WILL FINALLY OPEN UP AND EJECT TO THE NORTHEAST TUESDAY AND
TUESDAY NIGHT. ANY PRECIPITATION WITH THIS TROUGH IS EXPECTED TO
REMAIN SOUTHEAST OF THE PANHANDLES. SOME CONVECTION MAY ALSO DEVELOP
TO OUR NORTH/NORTHWEST ALONG A SURFACE TROUGH EXTENDING SOUTHWEST
FROM THE CENTRAL PLAINS INTO SOUTHEAST CO AND NORTHEAST NM...BUT
EXPECT THIS CONVECTION TO REMAIN OUTSIDE OF THE CWA AS WELL. THUS THE
MAIN STORY WILL BE ANOTHER WARM DAY...WITH HIGHS TAGGING THE UPPER
80S TO MID 90S AS SOUTHWEST BREEZES INCREASE.

THINGS BECOME A LITTLE MORE INTERESTING BY WEDNESDAY. THE SOUTHERN
STREAM SHORTWAVE TROUGH WILL SLIDE EAST ACROSS OK DURING THE
DAY...WHILE A SURFACE LOW DROPS SOUTH ACROSS THE PANHANDLES ALLOWING
A WEAK COLD FRONT TO SLIP THROUGH NORTHERN AND WESTERN PORTIONS OF
THE AREA. MEANWHILE THE CYCLONIC FLOW AROUND THE SURFACE LOW WILL
MAINTAIN SOUTH/SOUTHEAST SURFACE WINDS ACROSS THE EASTERN
PANHANDLES...KEEPING DEEPER MOISTURE IN PLACE. THIS INCREASED LOW-
LEVEL MOISTURE ALONG WITH COOLER TEMPS ALOFT UNDER THE WESTERN
PERIPHERY OF THE DEPARTING SHORTWAVE WILL LEAD TO INCREASED
INSTABILITY...WITH MLCAPES AROUND 1500 J/KG POSSIBLE. SURFACE
CONVERGENCE ALONG WITH WEAKER CAPPING IN THESE EASTERN AREAS CLOSER
TO THE EXITING SHORTWAVE MAY BE SUFFICIENT TO INITIATE CONVECTION AND
THUS HAVE ADDED SOME LOW POPS. CANNOT RULE OUT SOME CONVECTION
FARTHER WEST ALONG THE WEAK COLD FRONT...BUT CONFIDENCE IS LOWER DUE
TO LESS MOISTURE AND INSTABILITY...AS WELL AS INCREASING SUBSIDENCE
WITH WESTERN EXTENT BEHIND THE AFOREMENTIONED TROUGH AND AN
APPROACHING SHORTWAVE RIDGE. INSTABILITY AND DEEP LAYER SHEAR /30-35
KTS/ WILL SUPPORT THE THREAT FOR A COUPLE STRONG TO SEVERE STORMS
ACROSS THE EAST IF CONVECTION DOES DEVELOP.

FOR THURSDAY INTO THE WEEKEND...ANY PRECIPITATION CHANCES WILL BECOME
TIED TO THE DRYLINE. ON THURSDAY...IT LOOKS LIKE THE DRYLINE WILL SET
UP ACROSS THE EASTERN PANHANDLES. THE BIG QUESTION IN TERMS OF
CONVECTIVE POTENTIAL ON THIS DAY IS CAPPING. HEIGHTS/TEMPS ALOFT WILL
BE ON THE INCREASE AS AN UPPER RIDGE TRANSLATES EAST OVER THE AREA.
THE GFS IS SLIGHTLY WARMER ALOFT ACROSS THE EAST /H7 TEMPS 10-12C/
VERSUS THE ECMWF /H7 TEMPS 9-10C/...AND THUS STRONGER WITH THE CAP.
HAVE KEPT POPS SILENT FOR NOW GIVEN THIS CONCERN...BUT WILL HAVE TO
KEEP AN EYE ON THIS TIMEFRAME FOR POSSIBLE INTRODUCTION OF LOW POPS.
IF ANYTHING DOES DEVELOP IT WILL LIKELY BE FAIRLY ISOLATED GIVEN A
LACK OF APPRECIABLE FORCING...BUT NEEDLESS TO SAY GIVEN THE TIME OF
YEAR AND DRYLINE SETUP...SOME STRONG TO SEVERE CONVECTION WOULD BE A
POSSIBILITY IF STORMS ARE ABLE TO DEVELOP. SOUTHWEST FLOW ALOFT
STRENGTHENS FRIDAY AND SATURDAY AHEAD OF AN EJECTING WESTERN TROUGH.
THIS STRONGER FLOW ALOFT AND RESULTANT DEEPENING OF THE LEE SURFACE
TROUGH/LOW WILL PROMOTE A DEEP DRY/WARM SOUTHWESTERLY FLOW ACROSS THE
AREA...WHICH WILL SERVE TO MIX THE DRYLINE FARTHER EAST EACH DAY. ON
FRIDAY...THE DRYLINE WILL LIKELY MIX TO THE EASTERN CWA BORDER OR
WESTERN OK...BEFORE MIXING FARTHER EAST INTO OK ON SATURDAY. THUS
HAVE KEPT THE FORECAST DRY FOR THESE DAYS. THE LATEST ECMWF IS A
LITTLE SLOWER TO EJECT THE WESTERN TROUGH AND THUS HANGS THE DRYLINE
BACK A LITTLE FARTHER WEST ON FRIDAY. IF THIS TREND CONTINUES...MAY
HAVE TO ENTERTAIN SOME LOW POPS IN THE FAR EAST ON FRIDAY /ALTHOUGH
CAPPING MAY STILL BE AN ISSUE WITH H7 TEMPS OF 12-14C OVERHEAD STILL
WELL OUT AHEAD OF THE UPPER TROUGH/. TEMPS WILL CONTINUE TO WARM LATE
WEEK...LIKELY INTO THE MID 90S IN MANY SPOTS AS H85 TEMPS SOAR TO
AROUND 30C FRIDAY AND SATURDAY.

A WEAK COLD FRONT WILL PUSH THROUGH SATURDAY NIGHT/SUNDAY...BRINGING
A BIT OF A COOL DOWN FOR SUNDAY. THIS LOOKS TO BE A DRY FRONTAL
PASSAGE ATTM AS ANY APPRECIABLE MOISTURE REMAINS CONFINED TO AREAS
EAST OF THE PANHANDLES.

KB

FIRE WEATHER...
WARM CONDITIONS WILL PREVAIL THROUGH THE UPCOMING WEEK...WITH HIGH
TEMPERATURES REACHING THE 80S AND 90S. AS A RESULT...MINIMUM RELATIVE
HUMIDITY VALUES WILL FALL TO LESS THAN 20 PERCENT ACROSS AT LEAST
PARTS OF THE PANHANDLES SEVERAL DAYS THIS WEEK. WINDS WILL BE BREEZY
FOR A TIME THIS MORNING...BUT THEN DECREASE TO AROUND 15 MPH OR LESS
THIS AFTERNOON. THUS NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS
ARE ANTICIPATED TODAY DESPITE RELATIVE HUMIDITIES FALLING TO 10 TO 15
PERCENT AREA WIDE. ELEVATED FIRE WEATHER CONDITIONS ARE EXPECTED
ACROSS ALL BUT THE SOUTHEAST TEXAS PANHANDLE ON TUESDAY AS SOUTH TO
SOUTHWEST WINDS INCREASE TO 15 TO 20 MPH WITH HIGHER GUSTS AND
RELATIVE HUMIDITIES FALL TO 10 TO 20 PERCENT. ELEVATED FIRE WEATHER
CONDITIONS MAY RETURN TO THE WESTERN PANHANDLES ON THURSDAY...THEN
EXPAND EAST ACROSS CENTRAL AND POSSIBLY EASTERN PORTIONS OF THE AREA
FRIDAY AND SATURDAY AS DRY WEST/SOUTHWESTERLY WINDS DEVELOP BEHIND A
DRYLINE.

KB

&&

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

&&

$$

15/09