Severe Thunderstorm Warning 4, NWS Amarillo, TX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AMARILLO TX
954 PM CDT FRI MAR 20 2009

.UPDATE...
LONG LIVED STORM LOCATED OVER BEAVER COUNTY THIS EVENING...WAS
PULSATING AS IT TRACKED SLOWLY EAST. UPSTREAM...SHOWERS AND
ISOLATED STORMS WERE DEVELOPING WEST AND SOUTH OF THE PANHANDLES...
AHEAD OF SLOW MOVING UPPER LEVEL DISTURBANCE. WE KEPT A SLIGHT CHANCE
FOR THE REMAINDER OF THE NIGHT SHOULD ANY OF THIS ACTIVITY CREEP INTO
THE AREA. OTHERWISE... THE REST OF THE FORECAST WILL REMAIN INTACT.

NUNEZ

&&

.PREV DISCUSSION... /ISSUED 622 PM CDT FRI MAR 20 2009/

AVIATION...
FOR THE 00Z TAFS...THE BIGGEST CONCERN WILL BE THE CHANCES OF
THUNDERSTORMS THROUGH THE TAF PERIOD. THE BEST CHANCES FOR STORMS ARE
BETWEEN 04 AND 08Z TONIGHT...AND AGAIN AFTER 20Z. THOUGH THE STORMS
ARE S AND W OF THE REGION NOW...AS THE TROUGH LIFTS OUT LATER THIS
EVENING STORMS COULD MOVE FURTHER NORTH AFFECTING KDHT AND KAMA. THE
OKLAHOMA PANHANDLE...INCLUDING KGUY...WILL ONLY HAVE A MINIMAL CHANCE
TONIGHT. THERE IS A RISK OF LOW CLOUDS BETWEEN 09 AND 16Z...THAT
COULD LOWER CEILINGS TO MVFR. CONSIDERING THE SOUTHERLY WINDS...AND
LOOKING AT TIME HEIGHT DISPLAYS FROM VARIOUS MODELS...BELIEVE KAMA
HAS THE BIGGEST RISK FOR LOW LEVEL STRATUS DURING THIS TIME PERIOD.
DUE TO ONGOING TECHNICAL ISSUES AT KGUY HAVE APPENDED AMD NOT SKED TO
THAT TAF FOR NOW.

SJOHNSON

PREV DISCUSSION... /ISSUED 338 PM CDT FRI MAR 20 2009/

DISCUSSION...
CONVECTION IS ALREADY UNDERWAY THIS AFTERNOON SOUTH AND WEST OF A
LINE FROM LUBBOCK TO CLOVIS AND IS EXPECTED TO EVENTUALLY IMPACT THE
PANHANDLES LATER THIS EVENING. SURFACE DEWPOINTS REMAIN IN THE UPPER
40S TO LOWER 50S ACROSS MOST OF THE AREA WITH TEMPS APPROACHING THE
CONVECTIVE TEMPERATURE. THE CU FIELD IS BUILDING AND WE COULD SEE A
FEW THUNDERSTORMS DEVELOP LATER THIS AFTERNOON IN AREAS OF ENHANCED
CONVERGENCE. ACCORDING TO THE LATEST ANALYSES...THE SOUTHWEST TX
PANHANDLE IS ALREADY UNCAPPED AND ESSENTIALLY WAITING FOR A TRIGGER.
I GENERALLY KEPT POPS IN THE 30 TO 40 PERCENT RANGE TONIGHT.
THUNDERSTORMS WILL BE POSSIBLE AGAIN ON SATURDAY AS A
MOIST...UNSTABLE AIRMASS REMAINS IN PLACE. SHEAR VALUES WILL BE MORE
IMPRESSIVE BY SATURDAY AFTERNOON WHICH WILL LEAD TO ENHANCED SEVERE
THREAT. CHANCE POPS WERE INCLUDED IN MOST OF THE CENTRAL AND EASTERN
ZONES. THIS THREAT WILL CONTINUE INTO THE EVENING HOURS AS UPPER
LEVEL SUPPORT SHOULD PROLONG THE CONVECTION AFTER PEAK HEATING
SUBSIDES.

SUNDAY APPEARS TO BE A BREEZY...YET DRY...DAY FOR THE PANHANDLES.
SOUTH WINDS ARE EXPECTED TO INCREASE TO 15 TO 25 MPH...WITH
TEMPERATURES CLIMBING INTO THE UPPER 70S AND LOWER 80S. I WOULD NOT
RULE OUT A FEW THUNDERSTORMS BY LATE AFTERNOON ACROSS THE EAST...BUT
CONFIDENCE IS QUITE LOW AT THIS TIME...SO THE FORECAST WILL REMAIN
DRY. HOWEVER...BY SUNDAY NIGHT...THE MAIN UPPER LOW WILL BE MOVING
OUT OF THE SOUTHWEST CONUS. THE CONCERN WITH THIS FEATURE IS THAT IT
MOVES FAR ENOUGH TO THE NORTH AT THE PANHANDLES GET DRY SLOTTED.
THIS WILL LEAVE THE CURRENT POPS IN THE FORECAST FOR SUNDAY EVENING
EXPENDABLE. SHEAR AND INSTABILITY SHOULD BE ADEQUATE FOR STRONG
STORMS IF THEY ARE ABLE TO DEVELOP BUT IT MAY ALL BE MOOT IF THE MID
LEVEL MOISTURE SHIFTS EAST. FOR NOW...GIVEN THE PARAMETERS...I HAVE
OPTED TO LEAVE THE MENTION OF PRECIP IN THE FORECAST.  A PACIFIC
COLD FRONT/DRYLINE WILL MOVE ACROSS THE AREA ON MONDAY. THIS WILL
RESULT IN WARM AND DRY CONDITIONS AREAWIDE...WITH STRONG WEST WINDS
THROUGHOUT THE DAY. AT THE CURRENT TIME...THE FORECAST CALLS FOR
MARGINAL WIND ADVISORY CRITERIA WIND SPEEDS /AROUND 35 MPH
SUSTAINED/. MODELS SUGGEST THAT THERE MAY BE A FEW THUNDERSTORMS IN
THE EXTREME EASTERN PANHANDLES DURING THE AFTERNOON...BUT GIVEN THE
STRONG DYNAMICS AND MID LEVEL FLOW...THE DRYLINE IS EXPECTED TO BE
WELL EAST OF THE PANHANDLES BY THE TIME CONVECTION SPARKS.

A COLD FRONT WILL TRAVERSE THE PANHANDLES MONDAY NIGHT...BRINGING
COOLER TEMPERATURES TO THE AREA TUESDAY. THIS SYSTEM LOOKS DRY WITH
MOST OF THE MID LEVEL MOISTURE REMAINING TO OUR NORTH AND EAST. BY
WEDNESDAY...THE LEE TROF WILL RESUME AS THE NEXT TROF DIGS INTO THE
WESTERN CONUS. THIS WILL RESULT IN BREEZY CONDITIONS AND
TEMPERATURES WARMING BACK TO NEAR 70 DEGREES.  SIMILAR CONDITIONS
ARE EXPECTED ON THURSDAY...WITH ANOTHER COLD FRONT PROGGED TO ARRIVE
BY FRIDAY. THIS WILL BRING COOLER TEMPS BACK TO THE AREA HEADING
INTO THE WEEKEND. POPS MAY BE WARRANTED FOR FRIDAY AND/OR SATURDAY
AS WELL...BUT WILL LEAVE THE FORECAST DRY FOR NOW GIVEN THE MODEL
UNCERTAINTIES.

JOHNSON

FIRE WEATHER...
FIRE WEATHER CONCERNS WILL REMAIN LOW ON SATURDAY GIVEN THE AMOUNT
OF LOW LEVEL MOISTURE AND PRECIPITATION IN THE AREA...BUT WILL
INCREASE BY SUNDAY AS SOUTHERLY 20FT WINDS INCREASE TO AROUND 20 MPH
AND RELATIVE HUMIDITIES FALL TO 25 TO 30 PERCENT IN THE WEST AND
CENTRAL PANHANDLES. FIRE WEATHER CONCERNS WILL BE ENHANCED ON
MONDAY AREAWIDE DUE TO VERY STRONG WEST WIND AND LOW RELATIVE
HUMIDITIES. GIVEN THE CURRENT FORECAST...IT APPEARS THAT WE WILL NOT
MEET CRITICAL RELATIVE HUMIDITY THRESHOLDS...BUT THIS WILL BE
SOMETHING TO WATCH NONETHELESS. HOWEVER...THE THREAT MAY BE MITIGATED
SOMEWHAT IF WE RECEIVE PRECIPITATION BETWEEN NOW AND THEN. BY
TUESDAY...COOLER TEMPERATURES AND LOW RELATIVE HUMIDITIES WILL KEEP
FIRE WEATHER CONDITIONS AT BAY...BUT ELEVATED CONCERNS MAY RETURN BY
WEDNESDAY AND THURSDAY.

JOHNSON

&&

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

&&

16/08

TEXAS/OKLAHOMA PANHANDLES HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE AMARILLO TX
330 PM CDT FRI MAR 20 2009

OKZ001>003-TXZ001>020-211100-
ARMSTRONG-BEAVER-CARSON-CIMARRON-COLLINGSWORTH-DALLAM-DEAF SMITH-
DONLEY-GRAY-HANSFORD-HARTLEY-HEMPHILL-HUTCHINSON-LIPSCOMB-MOORE-
OCHILTREE-OLDHAM-POTTER-RANDALL-ROBERTS-SHERMAN-TEXAS-WHEELER-
330 PM CDT FRI MAR 20 2009

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

.DAY ONE...

THERE IS A SLIGHT CHANCE TO CHANCE OF THUNDERSTORMS TONIGHT ACROSS
THE OKLAHOMA AND TEXAS PANHANDLES AS A MINOR UPPER LEVEL LOW PRESSURE
SYSTEM MOVES THROUGH THE SOUTHERN HIGH PLAINS. ANY STORMS THAT FORM
ARE EXPECTED TO REMAIN BELOW SEVERE LEVELS AT THIS TIME.

.DAYS TWO THROUGH SEVEN...

THUNDERSTORMS WILL BE POSSIBLE ACROSS ALL OF THE OKLAHOMA AND TEXAS
PANHANDLES ON SATURDAY AND SATURDAY NIGHT...AND OVER THE EASTERN
HALF OF THE PANHANDLES SUNDAY NIGHT. ISOLATED STORMS THAT FORM MAY
APPROACH OR BRIEFLY BECOME SEVERE...WITH MARGINALLY SEVERE HAIL AND
STRONG GUSTY WINDS THE PRIMARY THREATS.

SOUTHWEST TO WEST WINDS OF 25 TO 35 MPH WITH HIGHER GUSTS ARE
EXPECTED ON MONDAY ACROSS THE OKLAHOMA AND TEXAS PANHANDLES...AND
A WIND ADVISORY MAY BE REQUIRED. IN ADDITION...ELEVATED TO CRITICAL
FIRE WEATHER CONDITIONS WILL BE POSSIBLE ACROSS ALL OF THE OKLAHOMA
AND TEXAS PANHANDLES ON MONDAY DUE TO THE COMBINATION OF STRONG WINDS
AND LOW RELATIVE HUMIDITIES.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME.

ANDRADE