FXUS64 KEWX 251754
AFDEWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1154 AM CST FRI DEC 25 2009
.DISCUSSION...
CONTINUED WITH TRENDS FROM ON GOING FORECASTS. SCATTERED
HIGH CLOUDS ARE EXPECTED TO COME ACROSS THE REGION FROM THE
WEST AND SOUTHWEST TODAY...FROM THE ACTIVE SOUTHERN STREAM
WESTERLIES SOUTH OF THE LOW PRESSURE SYSTEM OVER THE CENTRAL
U.S. AS THIS LOW SLOWLY MOVES EAST ON SATURDAY THROUGH
SATURDAY NIGHT...A BRIEF CLEARING TREND IS EXPECTED AND
ANOTHER WAVE OF COLD AIR WILL COME ACROSS THE REGION FROM THE
NORTH ON SATURDAY AFTERNOON TO SATURDAY EVENING. MOSTLY SUNNY
CONDITIONS ARE EXPECTED ON SUNDAY WITH SCATTERED HIGH CLOUDS
COMING ACROSS FROM THE WEST AGAIN PER TRENDS AND FORECAST
SOLUTIONS. INCREASING CLOUDS ARE EXPECTED MONDAY THROUGH
MONDAY NIGHT...IN ADVANCE OF THE NEXT 500 HPA LOW OVER THE
SW U.S. THIS WILL CAUSE AN INCREASING CHANCE OF RAIN
MONDAY NIGHT THROUGH TUESDAY. THE CLOUDS AND SCATTERED
RAIN ON TUESDAY WILL LIMIT DAYTIME HIGHS...FOLLOWED BY
LESS CLOUDINESS ON WEDNESDAY IN THE DAYTIME AS THE 500 HPA
LOW OPENS TO A FASTER MOVING WAVE AND MOVES EAST QUICKLY.
ON WEDNESDAY TO THE WEST...ANOTHER 500 HPA TROF IS FORECAST
TO FORM IN THE ACTIVE SOUTHERN STREAM WESTERLIES ACROSS THE
SW U.S. AS THIS 2ND WAVE OF ENERGY LINGERS WEST OF THE REGION ON
THURSDAY...SOME INCREASING MOISTURE AND CLOUDS IS POSSIBLE
THURSDAY THRU THURSDAY NIGHT. FORECAST SOLUTIONS SHOW A SLIGHT
CHANCE OF RAIN OVER THE EAST TO SOUTHEAST PART OF THE AREA
LATE THURSDAY OR THURSDAY NIGHT. AS THIS 500 HPA TROF MOVES
OVER SOUTH CENTRAL TEXAS THURSDAY NIGHT...RAIN CHANCES WILL
MOVE EAST...AND DECREASING CLOUDS ARE EXPECTED FROM THE WEST.
THIS WILL OPEN THE GATE TO MOSTLY SUNNY CONDITIONS ON FRIDAY OF
NEXT WEEK...AS ANOTHER WAVE OF COLD AIR COMES ACROSS THE REGION
FROM THE NORTH AND NORTHWEST. THIS FITS TRENDS FROM RECENT
WEEKS...AS THE FAST AND ACTIVE SOUTHERN STREAM WESTERLIES
AFFECT THE AREA. FOR NEXT WEEKEND OF JAN. 2ND AND 3RD...FORECAST
SOLUTIONS SHOW DRY CONDITIONS FOR SATURDAY...FOLLOWED BY
INCREASING CLOUDS DEVELOPING SUNDAY THE 3RD THROUGH MONDAY
JAN. 4TH.
&&
.PREV DISCUSSION... /ISSUED 1127 AM CST FRI DEC 25 2009/
DISCUSSION...
SEE AVIATION FOR THE 18Z TAF DISCUSSION.
AVIATION...
VFR CONDITIONS WILL PREVAIL THIS AFTERNOON AND OVERNIGHT AS FEW/SCT
CIRRIFORM CLOUDS STREAM ACROSS SOUTH CENTRAL TEXAS. THE LEADING EDGE
OF A STRATOCU DECK AT AROUND 5K FT WILL MOVE INTO KSAT AROUND 20Z ON
SATURDAY AS GULF MOISTURE STREAMS NORTHWARD. SFC WINDS THIS AFTERNOON
WILL BECOME SOUTHERLY AT LESS THAN 10 KTS AS THE SFC HIGH LOCATED
ALONG THE MIDDLE TEXAS COAST MOVES EASTWARD. SFC WINDS WILL DECOUPLE
OVERNIGHT RESULTING IN LIGHT AND VARIABLE WINDS.
PREV DISCUSSION... /ISSUED 533 AM CST FRI DEC 25 2009/
DISCUSSION...
SEE AVIATION FOR 12Z TAF DISCUSSION.
AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. A FEW CEILINGS MAY
APPROACH MVFR LEVELS AT SAT AFTER 12Z SATURDAY WHEN A WEAK
DISTURBANCE BUILDS LOWER LEVEL MOISTURE AND INSTABILITY ALONG THE
TX COAST. A FEW GUSTS TO AROUND 18 KTS REMAINS POSSIBLE EARLY THIS
MORNING...BUT THE FAST ZONAL PATTERN SHOULD REDUCE NORTHERLY WINDS
AND RETURN A SOUTH WIND TO AREAS NEAR AND WEST OF SAT THIS
AFTERNOON. THE WIND SHOULD DECREASE TONIGHT AND BECOME MOSTLY OUT
OF THE N/NE FOR SATURDAY MORNING.
PREV DISCUSSION... /ISSUED 442 AM CST FRI DEC 25 2009/
DISCUSSION...
COLD ADVECTION CONTINUES AS SURFACE HIGH BUILDS INTO SOUTH CENTRAL
TEXAS EARLY THIS MORNING AS CIRRUS INDICATES THE APPROACH OF YET
ANOTHER UPPER LEVEL SHORTWAVE. SURFACE HIGH MOVES OFF TO THE EAST
TODAY ALLOWING SOUTHERLY FLOW TO RETURN, HOWEVER WITH CIRRUS AND
ONGOING FLOW OFF THE SNOW FIELD TO OUR NORTH, HAVE GONE COLDER
THAN MAV AND CLOSER TO MET TEMPERATURES FOR TODAY AND TONIGHT.
ISENTROPIC LIFT AND A COASTAL LOW DEVELOP SATURDAY INTO SATURDAY
EVENING AS THE SHORTWAVE MOVES ACROSS SOUTHERN TEXAS. HAVE GONE
WITH SLIGHT CHANCE POPS FOR LIGHT RAIN OR PERHAPS DRIZZLE ACROSS
AREAS ALONG AND EAST OF I-35. THE CLOUDS WILL KEEP HIGHS SATURDAY
AGAIN CLOSER TO MET. COASTAL LOW AND SHORTWAVE MOVE OFF TO THE
EAST SATURDAY NIGHT ENDING THE POPS. MODELS CONTINUE CONSISTENCY
AND CONSENSUS ISSUES FOR MUCH OF NEXT WEEK. HAVE MAINTAINED POPS
FOR LATE MONDAY NIGHT THROUGH WEDNESDAY NIGHT AS A SERIES OF UPPER
LEVEL SHORTWAVES MOVE ACROSS THE AREA. MODEL SOUNDINGS SHOW THE
POTENTIAL FOR SLEET OR SNOW HAS DECREASED AND HAVE REMOVED THEIR
MENTION. HOWEVER, EXPECT NUMEROUS CHANGES TO THE FORECAST FOR NEXT
WEEK AS MODELS EVENTUALLY CONVERGE ON A SOLUTION. FYI, THE ECMWF
CONTINUES TO SHOW AN ARCTIC AIRMASS PLUNGING INTO SOUTH CENTRAL
TEXAS AFTER THE NEW YEAR.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 51 32 50 34 56 / 0 - 10 20 -
AUSTIN BERGSTROM INTL AIRPORT 51 26 50 29 56 / 0 - 10 20 -
NEW BRAUNFELS MUNI AIRPORT 53 30 50 32 57 / 0 - 20 20 -
BURNET MUNI AIRPORT 48 28 49 28 53 / 0 - 10 - -
DEL RIO INTL AIRPORT 56 33 58 31 59 / 0 - - - -
GEORGETOWN MUNI AIRPORT 48 27 50 30 52 / 0 - 10 10 -
HONDO MUNI AIRPORT 55 29 52 31 58 / 0 - 10 - -
SAN MARCOS MUNI AIRPORT 52 30 50 32 57 / 0 - 20 20 -
LA GRANGE - FAYETTE REGIONAL 52 31 50 35 57 / 0 - 30 30 -
SAN ANTONIO INTL AIRPORT 54 31 50 35 58 / 0 - 20 10 -
STINSON MUNI AIRPORT 55 33 50 36 59 / 0 - 20 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
08/13/PM/04/18
