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000
FXUS64 KAMA 261733
AFDAMA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO TX
1133 AM CST THU FEB 26 2015

.AVIATION...
ACTIVE WEATHER WILL LEAD TO A LOW CONFIDENCE 18Z TAF CYCLE. A
LINGERING BAND OF SNOW MOVING ACROSS THE TEXAS PANHANDLE WILL
CONTINUE TO IMPACT THE KAMA AND KDHT TERMINALS THROUGH THE FIRST HOUR
OR TWO OF THIS TAF CYCLE. ONCE THIS PRECIP SUBSIDES...MVFR CONDITIONS
WILL IMPROVE TO VFR WHILE MID CLOUDS PERSIST INTO THE OVERNIGHT
HOURS. KGUY IS ALSO EXPECTED TO BREAK OUT OF THE LOW CLOUDS BY THE
EARLY AFTERNOON. LIGHT WINDS WILL SLOWLY ROTATE TO A MORE EASTERLY TO
SOUTH EASTERLY WHEN THE NEXT ROUND OF FROZEN PRECIPITATION IS
EXPECTED. SNOW WILL BEING TO IMPACT THE TERMINALS FROM WEST TO EAST
STARTING AT 6Z TONIGHT. FLIGHT CONDITIONS WILL QUICKLY DECAY AS THIS
PRECIP STARTS AND HAVE LOWERED CATEGORIES TO IFR FOR ALL TERMINALS BY
TOMORROW MORNING. CONDITIONS COULD EASILY DECAY FURTHER IF SNOW
BANDING MOVES OVER THE TERMINALS. THESE POOR FLYING CONDITIONS ARE
EXPECTED TO PERSIST THROUGH THE END OF THIS TAF CYCLE.

&&

.PREV DISCUSSION... /ISSUED 533 AM CST THU FEB 26 2015/

DISCUSSION...
ACTIVE PERIOD OF WINTER WEATHER TO CONTINUE THROUGH THE NEXT
WEEK...CHARACTERIZED BY MULTIPLE MAINLY LIGHT ROUNDS OF PRECIPITATION.
PRECIPITATION TYPE BECOMES INCREASINGLY CHALLENGING OVER THE WEEKEND.

A NORTHWEST FLOW ALOFT REMAINS IN PLACE ACROSS THE REGION EARLY THIS
MORNING. A COUPLE OF EMBEDDED SHORTWAVES WITHIN THIS FLOW ARE THE
FOCUS FOR THE LIGHT PRECIPITATION THAT AFFECTED WESTERN PARTS OF THE
PANHANDLES OVERNIGHT...AND SOME ADDITIONAL ANTICIPATED LIGHT PRECIP
TODAY. THE INITIAL ROUND OF PRECIP TIED TO THE LEAD SHORTWAVE IS
PUSHING SOUTH OF THE PANHANDLES ATTM. TEMPERATURES WERE A LITTLE SLOW
TO COOL WITH THIS INITIAL ROUND...THUS A SIGNIFICANT PORTION OF IT
FELL AS RAIN RATHER THAN SNOW...KEEPING ANY SNOWFALL ACCUMS LIGHT
AND MAINLY CONFINED TO THE FAR WESTERN PANHANDLES. THE NEXT SHORTWAVE
DROPPING OUT OF CO WILL PROVIDE SOME WEAK FORCING ACROSS THE WESTERN
PANHANDLES TODAY. THIS WEAK FORCING FOR ASCENT ALONG WITH LOW-LEVEL
UPSLOPE FLOW WILL MAINTAIN CHANCES FOR LIGHT SNOW ACROSS THE WESTERN
PANHANDLES TODAY INTO THIS EVENING. EXPECT ANY ADDITIONAL
ACCUMULATIONS THROUGH THIS TIME TO REMAIN BELOW AN INCH. WILL KEEP
THE WINTER WEATHER ADVISORY IN EFFECT ACROSS THE WESTERN PANHANDLES
TODAY AS ROADWAYS WILL LIKELY BE SLICK IN SPOTS FROM THE LIGHT SNOW
ALONG WITH FREEZING OF THE RAIN THAT PRECEDED THE SNOW LAST NIGHT.
ALTHOUGH ANY ADDITIONAL SNOW THROUGH THIS EVENING SHOULD BE
LIGHT...SNOW WILL PICK BACK UP LATER TONIGHT. FARTHER EAST ACROSS THE
PANHANDLES TODAY...COULD SEE A FEW FLURRIES BUT WEAKER FORCING AND
DRIER LOW-LEVEL AIR ADVECTING IN FROM THE NORTHEAST WILL PRECLUDE ANY
MEASURABLE SNOWFALL. CONTINUED COLD ADVECTION THROUGH THE DAY AS AN
ARCTIC SURFACE HIGH BUILDS SOUTH THROUGH THE PLAINS WILL KEEP HIGH
TEMPS IN THE LOW 20S TO LOW 30S.

AS ALLUDED TO ABOVE...ANOTHER ROUND OF SNOW IS EXPECTED TO SPREAD
EAST ACROSS THE PANHANDLES LATE TONIGHT INTO FRIDAY ASSOCIATED WITH
THE NEXT UPPER-LEVEL SHORTWAVE MOVING ACROSS THE AREA. ISENTROPIC
UPGLIDE WILL INCREASE WITH THE APPROACH OF THE SHORTWAVE
TONIGHT...LEADING TO DEEPLY MOISTENING PROFILES...FAVORABLE FOR A
BRIEF PERIOD OF LIGHT TO MODERATE SNOW. THIS NEXT ROUND OF SNOW WILL
BE QUITE PROGRESSIVE...WHICH SHOULD LIMIT AMOUNTS TO THE 2 TO 4 INCH
RANGE WITH A LITTLE LESSER ACCUMS OF 1 TO 3 INCHES EXPECTED ACROSS
THE NORTHEAST PANHANDLES. THE TIMING OF THE WINTER WEATHER ADVISORY
STILL FITS THIS SCENARIO WELL...SO NO CHANGES WERE NEEDED THERE. THE
SNOW WILL TAPER OFF FROM WEST TO EAST DURING THE DAY ON FRIDAY AS
LIFT FROM THE SHORTWAVE DEPARTS. SHOULD SEE ANOTHER BRIEF BREAK IN
THE PRECIP BEFORE THE NEXT WEAK SHORTWAVE/JET STREAK QUICKLY SLIDES
ACROSS LATE FRIDAY NIGHT INTO SATURDAY MORNING. BEST FORCING FROM
THIS WAVE LOOKS TO BE ACROSS THE NORTHERN PANHANDLES...WHERE ANOTHER
INCH OR TWO OF SNOW COULD FALL DURING THIS TIME. TEMPS WILL REMAIN
VERY COLD ON FRIDAY...WITH HIGHS ONLY REACHING THE TEENS TO AROUND
20. PARTS OF THE AREA MAY NEED A WIND CHILL ADVISORY FRIDAY MORNING
AS WIND CHILLS ARE EXPECTED TO DROP TO ZERO TO 10 BELOW.

PRECIP CHANCES DECREASE SATURDAY AFTERNOON IN WAKE OF THE LATEST
SHORTWAVE EXITING THE AREA. HOWEVER...WEAK ISENTROPIC LIFT WILL
PERSIST GIVEN THE LARGE SCALE PATTERN /WEST TO SOUTHWEST MID-LEVEL
FLOW ABOVE EAST TO SOUTHEAST FLOW AT LOW LEVELS/...THUS SOME
SCATTERED FLURRIES OR VERY LIGHT FZDZ COULD LINGER SATURDAY AFTERNOON.
FORECAST SOUNDINGS SHOW DRYING FROM THE MID-LEVELS DOWNWARD DURING THE
DAY. ACROSS THE WESTERN AND CENTRAL PANHANDLES...THINK THIS DRYING
WILL BE PROGRESSIVE ENOUGH THROUGH THE LOW LEVELS FOR THE LIGHT SNOW
TO JUST END. HOWEVER ACROSS THE EASTERN PANHANDLES...LOW-LEVELS
REMAIN SATURATED LONGER ONCE MOISTURE EVACUATES THE SNOW GROWTH
ZONE...SO COULD SEE A BIT OF FREEZING DRIZZLE IN THESE AREAS.

THE FORECAST BECOMES INCREASINGLY MESSY AND CHALLENGING SATURDAY
NIGHT THROUGH MONDAY MORNING. IT DOES APPEAR THAT ANY PRECIPITATION
DURING THIS TIME WILL BE LIGHT...DRIVEN PRIMARILY BY ISENTROPIC
LIFT/WARM AIR ADVECTION ABOVE THE COOLER NEAR SURFACE LAYER.
HOWEVER...PRECIPITATION TYPE IS A NIGHTMARE AS IT LOOKS LIKE THE
BAROCLINIC ZONE AND ASSOCIATED TRANSITION ZONE FOR PRECIP TYPES WILL
BE DRAPED ACROSS THE AREA DURING THIS TIME. THINK THE MAIN MESSAGE TO
GET ACROSS AT THIS POINT IS THAT A LIGHT WINTRY MIX IS EXPECTED
DURING THIS TIME. ALTHOUGH ANY ICE OR SNOW AMOUNTS APPEAR TO BE
LIGHT...ROADWAYS COULD VERY WELL BECOME SLICK DURING THIS
TIME...POTENTIALLY LEADING TO HAZARDOUS DRIVING CONDITIONS. TRIED TO
REFLECT THE MOST LIKELY PRECIP TYPES FOR THESE VARIOUS PERIODS IN THE
GRIDS...RANGING FROM SNOW TO SLEET TO FZRA OR FZDZ TO RAIN OR
DZ...ALTHOUGH THE DETAILS ARE SURE TO EVOLVE OVER THE NEXT FEW DAYS.
THE GFS WAS MOST AGGRESSIVE WITH THE WARM AIR ADVECTION DURING THIS
TIME AND BECAME A WARM OUTLIER...THUS LEANED MORE HEAVILY ON THE
NAM/ECMWF/CMC GEM FOR PRECIP TYPES. IT DOES APPEAR THAT BY MONDAY
AFTERNOON ANY PRECIP SHOULD BE ALL RAIN AS WARM AIR ADVECTION
CONTINUES TO DEEPEN AND STRENGTHEN DOWNSTREAM OF A DIGGING WESTERN
CONUS TROUGH. THIS WILL ALSO BRING MODERATING TEMPERATURES EARLY NEXT
WEEK.

THIS WESTERN TROUGH SHOULD FINALLY EJECT ACROSS THE PLAINS MID TO
LATE NEXT WEEK...SHOVING ANOTHER ARCTIC SURGE SOUTH AND BRINGING
ANOTHER SHOT OF LIGHT SNOW TOWARD THE WEDNESDAY TIMEFRAME.

KB

&&

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST FRIDAY
     FOR THE FOLLOWING ZONES: ARMSTRONG...CARSON...
     COLLINGSWORTH...DONLEY...GRAY...HANSFORD...HEMPHILL...
     HUTCHINSON...LIPSCOMB...MOORE...OCHILTREE...ROBERTS...
     SHERMAN...WHEELER.

     WINTER WEATHER ADVISORY UNTIL 3 PM CST FRIDAY FOR THE FOLLOWING
     ZONES: DALLAM...DEAF SMITH...HARTLEY...OLDHAM...POTTER...
     RANDALL.

OK...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST FRIDAY
     FOR THE FOLLOWING ZONES: BEAVER...TEXAS.

     WINTER WEATHER ADVISORY UNTIL 3 PM CST FRIDAY FOR THE FOLLOWING
     ZONES: CIMARRON.


&&

$$

14/02