FXUS64 KSJT 081144
AFDSJT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
544 AM CST TUE DEC 8 2009
.DISCUSSION...
SEE AVIATION SECTION.
&&
.AVIATION...
WITH A MOIST AND SHALLOW COLD AIRMASS...LIFR CLOUD CEILINGS ARE
OCCURRING AT THE TAF SITES ACROSS WEST CENTRAL TEXAS EARLY THIS
MORNING. AREAS OF FOG ARE ALSO OCCURRING WITH VISIBILITY LESS
THAN 1 MILE AT TIMES. PATCHY FREEZING DRIZZLE WILL CONTINUE
THROUGH EARLY THIS MORNING ACROSS THE BIG COUNTRY AND NORTHERN
CONCHO VALLEY...WHERE TEMPERATURES ARE JUST BELOW FREEZING.
FARTHER TO THE SOUTH...FOG AND DRIZZLE WILL OCCUR. THE LOW
CLOUDS AND FOG WILL QUICKLY DISSIPATE LATER THIS MORNING...AS
SOUTH TO SOUTHWEST WINDS DEVELOP AND DRIER AIR BEGINS TO ENTER THE
AREA. EXPECT VFR CONDITIONS AREAWIDE BY THIS AFTERNOON...WITH
SOUTHWEST WINDS INCREASING AND MUCH DRIER AIR INVADING THE REGION.
WIND GUSTS OVER 40 KT ARE POSSIBLE THIS AFTERNOON ACROSS THE BIG
COUNTRY WEST OF ABILENE...AND ACROSS THE THE CONCHO VALLEY
NORTHWEST OF SAN ANGELO. EXPECT AIRPORT WEATHER WARNING CRITERIA
TO BE MET AT THE ABILENE AIRPORT THIS AFTERNOON. WINDS WILL BE
GUSTY BUT NOT AS STRONG THIS AFTERNOON AT THE KSOA...KBBD AND KJCT
SITES. THE WINDS AREAWIDE BECOME WEST BY THIS EVENING AND WILL
SUBSIDE. WITH A COLD FRONTAL PASSAGE OVERNIGHT THE WINDS WILL
SHIFT TO THE NORTH-NORTHWEST.
&&
.PREV DISCUSSION... /ISSUED 352 AM CST TUE DEC 8 2009/
SHORT TERM...
SHORT-TERM PART OF THE FORECAST IS RATHER ACTIVE...WITH A POTENT
UPPER TROUGH AND SURFACE LOW PRESSURE SYSTEM FORECAST TO MOVE OUT
OF THE SOUTHERN/CENTRAL ROCKIES ACROSS THE SOUTHERN/CENTRAL PLAINS.
SHALLOW COLD AIR MASS...WHICH BECAME ENTRENCHED ACROSS WEST CENTRAL
TEXAS DURING THE PAST 18 HOURS...REMAINS IN PLACE EARLY THIS MORNING.
AREAS OF FOG AND FREEZING DRIZZLE OCCURRING ACROSS ROUGHLY THE
NORTHERN THIRD OF OUR COUNTIES WHERE TEMPERATURES REMAIN BELOW
FREEZING. FOG AND DRIZZLE ALSO OCCURRING FARTHER TO THE SOUTH.
VISIBILITIES HAVE DROPPED TO ONE QUARTER MILE AT TIMES. TEMPERATURES
ACROSS OUR CENTRAL AND NORTHERN COUNTIES...HOWEVER...HAVE CREPT UP
A COUPLE OF DEGREES DURING THE PAST SEVERAL HOURS. AS THE UPPER
SYSTEM APPROACHES AND SURFACE LOW PRESSURE DEVELOPS IN THE
NORTHERN TX PANHANDLE OR NORTHEASTERN CORNER OF NEW MEXICO LATER
THIS MORNING...THE SHALLOW COLD AIR MASS WILL ERODE FROM SOUTH TO
NORTH ACROSS WEST CENTRAL TX. THE GFS SUGGESTS THE POSSIBILITY OF
SOME ELEVATED CONVECTION DEVELOPING BY 12Z JUST NORTHEAST AND
EAST OF HASKELL/THROCKMORTON COUNTIES...AS LIFT FROM APPROACHING
SYSTEM IMPINGES ON THE AREA AND MID-LEVEL LAPSE RATES STEEPEN...
ALONG WITH STRENGTHENING LOW-LEVEL JET AND INCREASING PRECIPITABLE
WATER VALUES. WILL BE MONITORING OUR NORTHEASTERN COUNTIES FOR
POSSIBLE DEVELOPMENT OF FREEZING RAIN EARLY THIS MORNING...WHERE
SURFACE TEMPERATURES ARE NEAR THE FREEZING MARK. WITH ALL OF THE
ABOVE MENTIONED CONSIDERATIONS...WILL ALLOW THE FREEZING RAIN
ADVISORY TO CONTINUE UNTIL EXPIRATION AT 15Z THIS MORNING.
AS THE UPPER SYSTEM AND SURFACE LOW START TO MOVE ACROSS THE
SOUTHERN PLAINS/RED RIVER VALLEY AROUND MIDDAY...DRY SLOT WILL
AGGRESSIVELY WORK EAST INTO WEST CENTRAL TEXAS. THIS WILL
RESULT IN A QUICK CLEARING TREND WITH TEMPERATURES RAPIDLY
REBOUNDING THIS AFTERNOON. THE MAIN CONCERN FOR THIS AFTERNOON
IS THE STRONG GUSTY SOUTHWEST-WEST WINDS WHICH WILL OCCUR
ACROSS MUCH OF THE NORTHERN HALF OF WEST CENTRAL TEXAS. WE ARE
UPGRADING THE HIGH WIND WATCH TO A HIGH WIND WARNING ACROSS
FISHER...NOLAN AND STERLING COUNTIES. THIS ALSO MATCHES WITH
THE SURROUND WFO AREA HIGH WIND WARNING. ALSO ISSUING A WIND
ADVISORY ACROSS THE REST OF THE BIG COUNTRY AND CONCHO VALLEY...
EXTENDING INTO COLEMAN COUNTY. THE WARNING AND ADVISORY
PRODUCTS WILL BE IN EFFECT FROM NOON TO 6 PM. SOMETIMES
THESE TYPES OF EVENTS GENERATE BLOWING DUST OVER WEST TEXAS
AND CARRY IT EASTWARD ALOFT INTO WEST CENTRAL TEXAS. IN THIS
CASE HOWEVER...BELIEVE THE FAIRLY RECENT PRECIPITATION AND
MORE LIMITED TIME WINDOW FOR DRY AIR AND WIND WILL BE INHIBITING
FACTORS.
AS THE UPPER SYSTEM AND SURFACE LOW PULL AWAY QUICKLY TO
THE NORTHEAST TONIGHT...COLD FRONT WILL DROP SOUTH ACROSS
WEST CENTRAL TEXAS. THE BEST COLD AIR ADVECTION WILL BE
INTO THE BIG COUNTRY OVERNIGHT. COLD FRONTAL PASSAGE WILL
BE DRY AND EXPECT SKIES TO BE MOSTLY CLEAR TONIGHT.
LONG TERM...
MOST OF THE IMPORTANT WEATHER IN THE SHORT TERM AND THIS IS WHERE
THE TIME WAS INVESTED THIS MORNING. TEMPERATURES ON WEDNESDAY WILL
AGAIN BE A CHALLENGE...AS SHALLOW ARCTIC AIR MASS LOOKS LIKE IT
WILL AGAIN MAKE FOR A VERY COLD DAY. SHOULD AT LEAST SEE SOME SUN
THOUGH...AS THE AIR MASS LOOKS DRY. HAVE UNDERCUT GUIDANCE NUMBERS FOR
WEDNESDAY AND WEDNESDAY NIGHT.
SOUTHERN STREAM JET SWEEPS A SHORTWAVE ACROSS THE AREA FOR FRIDAY.
LATEST MODELS LOOK A LITTLE DRIER THAN THEY DID BEFORE...BUT WORTH
KEEPING THE SMALL POPS IN FOR THE MOMENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 65 28 42 26 50 / 10 0 0 10 0
SAN ANGELO 70 33 49 28 55 / 10 0 0 10 0
JUNCTION 71 40 54 27 58 / 10 0 0 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 9 AM CST THIS MORNING FOR THE
FOLLOWING ZONES: BROWN...CALLAHAN...COKE...COLEMAN...CONCHO...
FISHER...HASKELL...IRION...JONES...NOLAN...RUNNELS...
SHACKELFORD...STERLING...TAYLOR...THROCKMORTON...TOM GREEN.
WIND ADVISORY FROM NOON TODAY TO 6 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: CALLAHAN...COKE...COLEMAN...CONCHO...HASKELL...
IRION...JONES...RUNNELS...SHACKELFORD...TAYLOR...THROCKMORTON...
TOM GREEN.
HIGH WIND WARNING FROM NOON TODAY TO 6 PM CST THIS EVENING FOR
THE FOLLOWING ZONES: FISHER...NOLAN...STERLING.
&&
$$
19/07/19
