Winter Weather in Texas, December 31, 2012

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AMARILLO TX
1132 PM CST SUN DEC 30 2012

.UPDATE...
UPDATED FOR 06Z AVIATION DISCUSSION.

&&

.AVIATION.../06Z TAFS/

COMPLICATED WEATHER FORECAST FOR ALL THREE TAF SITES OVER THE NEXT
18 HOURS INCLUDING WINTRY PRECIPITATION AND IFR TO POSSIBLY LIFR
CEILINGS EXPECTED.

KAMA...THE LEAST AMOUNT OF CONFIDENCE IN THE FORECAST FOR MAINLY
PRECIPITATION TYPE IS AT KAMA. HOWEVER...CONFIDENCE IS HIGH AS FAR AS
THE EXPECTED DETERIORATION OF CEILINGS AND TIMING OF PRECIPITATION.
BELIEVE PRECIPITATION WILL CONTINUE AS -RA...SWITCHOVER TO -FZRA...
BEFORE SWITCHING BACK TO -RA WITH POSSIBLY -SN MIXED IN DURING THE
TIME FRAME OF 06Z-15Z. AT THE SAME TIME...LOW MVFR...IFR AND POSSIBLY
LIFR CEILINGS CAN BE EXPECTED WITH SLIGHT IMPROVEMENT AFTER 22Z TO
LOW MVFR...ALTHOUGH WOULD NOT BE SURPRISED IF IFR CEILINGS REMAIN
WELL BEYOND 01/00Z.

KDHT AND KGUY...A LITTLE MORE CONFIDENCE EXISTS WHERE MOSTLY -SN WILL
BE THE MAIN PRECIPITATION TYPE WITH THE ONSET OF PRECIPITATION BEING
-RA AND POSSIBLY BRIEF -FZRA. TIMING OF PRECIPITATION WILL BE 09Z-
18Z FOR KDHT AND 10Z-21Z FOR KGUY WITH LOW MVFR...IFR AND POSSIBLY
LIFR CEILINGS EXPECTED. ONCE AGAIN...IMPROVEMENT OF CEILINGS APPEAR
UNLIKELY WITH LOW MVFR AND IFR CEILINGS CONTINUING WELL BEYOND
01/00Z.

KNS

&&

.DISCUSSION... /ISSUED 1000 PM CST SUN DEC 30 2012/

INCREASED POPS AND ADJUSTED WEATHER TYPES BEFORE MIDNIGHT...
OTHERWISE NO MAJOR CHANGES WERE MADE AT THIS TIME.

DISCUSSION...
COMPLICATED FORECAST STILL IN PLAY FOR THE NEXT 18 TO 24 HOURS FOR
THE PANHANDLES AS WINTRY PRECIPITATION WILL DEVELOP OVER MUCH OF THE
AREA OVERNIGHT.

CURRENTLY...A FEW RADAR ECHOS CAN BE SEEN FROM KAMA RADAR. AS A
RESULT...MADE A FEW PHONE CALLS TO SEE WHAT TYPE OF PRECIPITATION IS
FALLING AND ALL REPORTED LIGHT RAIN SO FAR WITH THE HEREFORD AWOS
REPORTING UNKNOWN PRECIP. TEMPERATURES ACROSS THE SOUTHERN TEXAS
PANHANDLE STILL REMAIN WELL ABOVE FREEZING SO THINK THIS FIRST ROUND
OF PRECIPITATION WILL REMAIN ALL RAIN BEFORE HEADING NORTH OF THE
CANADIAN RIVER.

ONCE THE PRECIPITATION BECOMES HEAVIER DURING THE NEXT SEVERAL
HOURS...DO THINK SOME EVAPORATIONAL COOLING WILL TAKE PLACE AND
TEMPERATURES WILL DECREASE CLOSER TO FREEZING ACROSS THE SOUTHERN
TEXAS PANHANDLES. UNFORTUNATELY...AMARILLO PROPER APPEARS TO BE
RIGHT ON THE EDGE OF THE FREEZING MARK MAKING THE FORECAST EXTREMELY
DIFFICULT AS TO HOW MUCH RAIN...FREEZING RAIN...OR SNOW THE CITY WILL
SEE. SEVERAL DIFFERENT SCENARIOS COULD SET UP WITH AN ALL RAIN
SCENARIO...OR A RAIN/THEN FREEZING RAIN/THEN SNOW SCENARIO...OR COLD
RAIN AND THEN LIGHT SNOW AS THE SYSTEM MOVES OUT OF THE AREA. IF
TEMPERATURES REMAIN SEVERAL DEGREES ABOVE FREEZING AND DO NOT FALL
OVER THE NEXT COUPLE OF HOURS...BELIEVE THE ALL RAIN SCENARIO WILL
WIN OUT. STAY TUNED.

OUTSIDE OF AMARILLO...STILL THINK THE SOUTHEAST TEXAS PANHANDLE WILL
REMAIN ALL RAIN FOR THE DURATION OF THIS SYSTEM WHILE AREAS NORTH OF
THE CANADIAN RIVER MAY START OUT AS LIGHT FREEZING RAIN BUT
EVENTUALLY CHANGE TO ALL SNOW OVERNIGHT. ONCE AGAIN...THE EASTERN
OKLAHOMA AND NORTHEAST TEXAS PANHANDLES APPEAR TO HAVE THE GREATEST
CHANCE TO SEE THE HIGHEST AMOUNTS OF PRECIPITATION AND SNOWFALL
TOTALS. ALL PRECIPITATION APPEARS TO EXIT THE AREA BY MONDAY EVENING.

AS FAR AS THE FORECAST...NO MAJOR CHANGES WERE MADE OTHER THAN TO
INCREASE POPS TO ACCOUNT FOR ONGOING PRECIP. WILL UPDATE THE WINTER
WEATHER ADVISORY AND KEEP THINGS STATUS QUO ALTHOUGH THE GREATEST
UNCERTAINTY DOES LIE WITHIN THE SOUTHWESTERN TEXAS PANHANDLE
INCLUDING AMARILLO. THIS WILL BE MONITORED VERY CLOSELY OVERNIGHT.

KNS

&&

.PREV DISCUSSION... /ISSUED 348 PM CST SUN DEC 30 2012/

WINTRY MIX TO IMPACT MUCH OF THE PANHANDLES TONIGHT INTO NEW YEARS
EVE.

THE FORECAST REMAINS COMPLEX THROUGH THE NEXT 24 HOURS. LONGWAVE MID
/UPPER-LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN/CA WILL CONTINUE
TO PROPAGATE EAST...CENTERING ITSELF OVER THE CENTRAL AND SOUTHERN
ROCKIES BY MONDAY AFTERNOON. LEADING POTENT SHORTWAVE CURRENTLY OVER
BAJA WILL EJECT NORTHEAST AHEAD OF THE MEAN UPPER TROUGH...LEADING TO
INCREASING PRECIP CHANCES STARTING LATE THIS EVENING. ISENTROPIC LIFT
WILL BE ON THE INCREASE THIS EVENING AND OVERNIGHT AHEAD OF THE
APPROACHING WAVE. THIS LIFT ALONG WITH MOISTURE ADVECTION AT LOW TO MID-
LEVELS SHOULD BE SUFFICIENT TO GENERATE PRECIP STARTING POSSIBLY AS
EARLY AS LATE THIS EVENING...THEN INCREASING IN COVERAGE AFTER
MIDNIGHT. PRECIP CHANCES TO CONTINUE DURING THE DAY TOMORROW AS
DYNAMICS WORK ACROSS...BEFORE ENDING BY EARLY MONDAY EVENING.

MODELS ARE IN DECENT AGREEMENT WITH THE OVERALL SCENARIO DESCRIBED
ABOVE...BUT CONTINUE TO DIFFER ON THE FINE DETAILS...WHICH WILL
UNFORTUNATELY MAKE ALL THE DIFFERENCE WHEN IT COMES TO SENSIBLE
WEATHER IN ANY GIVEN LOCATION. MODELS HAVE TRENDED A LITTLE QUICKER
OVERALL WITH THE COLD FRONT WORKING SOUTHEAST AFTER MIDNIGHT
TONIGHT...GIVING RISE TO A LITTLE HEIGHTENED CONCERN FOR A POSSIBLY
MORE SIGNIFICANT WINTRY MIX ACROSS THE SOUTHWEST TX PANHANDLE WHEN
CONSIDERING THIS COOLING ALONG WITH SOME DYNAMIC COOLING FROM THE
APPROACHING UPPER TROUGH. THE BIGGEST UNCERTAINTY AT THIS POINT
CONCERNS HOW FAST AND HOW INFLUENTIAL THE MID-LEVEL DRY SLOT WILL BE
FOR THE PANHANDLES. MODELS HAVE FLIP FLOPPED WITH THIS THE LAST FEW
DAYS AND CONTINUE TO DO SO TODAY. THIS WILL PARTICULARLY IMPACT HOW
MUCH PRECIPITATION THE WESTERN PANHANDLES ULTIMATELY RECEIVE. TAKING
A LOOK AT WATER VAPOR IMAGERY AND CONSIDERING THE MYRIAD OF
GUIDANCE...THINK WE/LL SEE A DECENT SHOT FOR PRECIP LATE TONIGHT INTO
MONDAY MORNING BEFORE THE DRY SLOT STARTS TO SHUT THINGS OFF FROM
SOUTHWEST TO NORTHEAST BY LATE MORNING. HAVE PLAYED THE FORECAST THIS
WAY...INCREASING POPS IN MANY LOCATIONS.

STILL LOOKS LIKE THE HEAVIEST PRECIP AMOUNTS WILL BE ACROSS THE
EASTERN PANHANDLES...WHILE THE COLDER AIR WILL GRADUALLY ADVECT
SOUTHEAST OVERNIGHT. GREATEST WINTER WEATHER IMPACTS WILL LIKELY BE
WHERE THESE INTERSECT...ALTHOUGH IT WON/T TAKE MUCH LIGHT SNOW/ICING
AT ALL TO MAKE FOR A PERIOD OF HAZARDOUS TRAVEL LATE TONIGHT AND
MONDAY. WITH THAT BEING SAID...HAVE EXPANDED THE WINTER WEATHER
ADVISORY TO COVER ALL BUT THE SOUTHEAST TX PANHANDLE WHERE THE PRECIP
IS EXPECTED TO REMAIN AS ALL RAIN /A COLD RAIN THOUGH WITH TEMPS JUST
ABOVE FREEZING/. ELSEWHERE...STILL LOOKS LIKE A WINTRY MIX OF
RAIN/FREEZING RAIN/SNOW IS POSSIBLE...WITH A BRIEF PERIOD OF SLEET
ALSO POSSIBLE DURING THE TRANSITION PHASE. THE GENERAL IDEA IS FOR
THE PRECIPITATION TO TRANSITION FROM RAIN TO FREEZING RAIN...THEN
EVENTUALLY TO SNOW AS THE LOW-LEVEL WARM NOSE IS ERODED IN THE
DEEPENING COLD AIR. PRECIPITATION AMOUNTS VERY TOUGH TO PIN DOWN
GIVEN UNCERTAINTIES WITH BOTH THE DRY SLOT AND PRECIP TYPE. AT THIS
TIME HOWEVER...FORECASTING 1 TO 3 INCH SNOWS ACROSS THE NORTHERN HALF
OF THE AREA WITH THE HIGHEST OF THESE IN THE EASTERN OK PANHANDLE AND
FAR NORTHEAST TX PANHANDLE. UP TO AN INCH EXPECTED ACROSS THE
SOUTHWEST/SOUTH CENTRAL TX PANHANDLE. ANY ICE ACCUMULATIONS FROM
FREEZING RAIN SHOULD BE LIGHT...LESS THAN A TENTH OF AN INCH. PRECIP
EXPECTED TO TAPER OFF FROM SOUTHWEST TO NORTHEAST LATE MONDAY MORNING
THROUGH EARLY MONDAY EVENING AS DRY SLOT WORKS ACROSS. COULD SEE A
BRIEF PERIOD OF LIGHT FREEZING DRIZZLE AS MID-LEVELS DRY OUT...BUT
FORECAST SOUNDINGS SHOW THE DRYING HAPPENING PRETTY QUICKLY...LIMITING
THE DRIZZLE THREAT. ALSO...TEMPS ARE STILL AROUND -6C OR COLDER IN
THE LOW-LEVEL MOIST LAYER...WHICH WOULD TEND TO FAVOR TAPERING LIGHT
SNOW OR FLURRIES RATHER THAN A MORE PRONOUNCED FREEZING DRIZZLE
THREAT. WILL NEED TO KEEP AN EYE OUT FOR SOME POSSIBLE FOG
DEVELOPMENT LATE MONDAY NIGHT/TUESDAY MORNING.

TUESDAY AND BEYOND...DRY CONDITIONS WITH TEMPERATURES NEAR OR BELOW
NORMAL ARE ANTICIPATED. MEAN UPPER TROUGH WILL REMAIN IN THE
REGION...HOWEVER DRY LOW TO MID-LEVELS SHOULD INHIBIT ANY
PRECIPITATION. TUESDAY LOOKS TO BE THE COLDEST DAY...WITH MODERATING
TEMPERATURES THEREAFTER.

KB

&&

.FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED THROUGH
NEXT WEEKEND.

KB

&&

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...WINTER WEATHER ADVISORY UNTIL 6 PM CST MONDAY FOR THE FOLLOWING
     ZONES: CARSON...DALLAM...DEAF SMITH...HANSFORD...HARTLEY...
     HEMPHILL...HUTCHINSON...LIPSCOMB...MOORE...OCHILTREE...
     OLDHAM...POTTER...RANDALL...ROBERTS...SHERMAN.

OK...WINTER WEATHER ADVISORY UNTIL 6 PM CST MONDAY FOR THE FOLLOWING
     ZONES: BEAVER...CIMARRON...TEXAS.

&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE AMARILLO TX
1035 PM CST SUN DEC 30 2012

OKZ001>003-TXZ001>020-311400-
CIMARRON-TEXAS-BEAVER-DALLAM-SHERMAN-HANSFORD-OCHILTREE-LIPSCOMB-
HARTLEY-MOORE-HUTCHINSON-ROBERTS-HEMPHILL-OLDHAM-POTTER-CARSON-
GRAY-WHEELER-DEAF SMITH-RANDALL-ARMSTRONG-DONLEY-COLLINGSWORTH-
1035 PM CST SUN DEC 30 2012

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

.DAY ONE...TONIGHT.

PRECIPITATION WILL SPREAD ACROSS THE PANHANDLES OVERNIGHT...WITH
RAIN INITIALLY TRANSITIONING TO FREEZING RAIN AND SNOW ACROSS ALL BUT
THE SOUTHEAST TEXAS PANHANDLE BY DAYBREAK MONDAY. A WINTER WEATHER
ADVISORY IS IN EFFECT FOR THE OKLAHOMA PANHANDLE AND ALL BUT THE
SOUTHEAST TEXAS PANHANDLE.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR THE OKLAHOMA
PANHANDLE AND ALL BUT THE SOUTHEAST TEXAS PANHANDLE THROUGH 6 PM CST
MONDAY.

SNOW WILL CONTINUE ACROSS THE OKLAHOMA PANHANDLE AND NORTHWEST TEXAS
PANHANDLE...WITH A WINTRY MIX OF SNOW AND LIGHT FREEZING RAIN
CONTINUING TO THE SOUTH. STORM TOTAL SNOWFALL ACCUMULATIONS OF 1 TO
3 INCHES ARE EXPECTED ACROSS THE OKLAHOMA PANHANDLE AND NORTHERN
TEXAS PANHANDLE...WITH THE HIGHEST OF THESE ACROSS THE EASTERN
OKLAHOMA PANHANDLE. SNOWFALL ACCUMULATIONS UP TO AN INCH ARE POSSIBLE
ACROSS THE SOUTHWEST AND SOUTH CENTRAL TEXAS PANHANDLE. LIGHT ICE
ACCUMULATIONS OF LESS THAN A TENTH OF AN INCH MAY ALSO RESULT FROM
THE FREEZING RAIN.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME. THE NATIONAL
WEATHER SERVICE IN AMARILLO WOULD APPRECIATE ANY REPORTS OF
PRECIPITATION TYPE AND AMOUNTS THROUGH MONDAY.

KNS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AMARILLO TX
1126 PM CST SUN DEC 30 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1015 PM     FREEZING RAIN    1 W AMARILLO            35.20N 101.83W
12/30/2012  U0.00 INCH       POTTER             TX   BROADCAST MEDIA

&&

EVENT NUMBER AMA1200817

K. SCOTTEN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AMARILLO TX
1128 PM CST SUN DEC 30 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1052 PM     FREEZING RAIN    5 WSW AMARILLO          35.17N 101.90W
12/30/2012  U0.00 INCH       RANDALL            TX   BROADCAST MEDIA

&&

EVENT NUMBER AMA1200818

K. SCOTTEN