FXUS64 KEWX 261746 AAC
AFDEWX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1146 AM CST SAT DEC 26 2009
.DISCUSSION...
SEE AVIATION SECTION.
&&
.AVIATION...
A STRATUS DECK IS EXPANDING NORTH INTO THE I-35 CORRIDOR AND WILL
AFFECT I-35 TERMINALS THIS AFTERNOON WITH VFR AND MVFR CIGS. KDRT
WILL REMAIN VFR THROUGH THE PERIOD. A LIGHT ENE LOW LEVEL FLOW
WILL SHIFT TO THE NNE LATER THIS EVENING AS A REINFORCING SHOT OF
COLD AIR SLIDES SOUTH INTO THE AREA. A LIGHT ESE LOW LEVEL FLOW
WILL PERSIST AT KDRT.
&&
.PREV DISCUSSION... /ISSUED 1026 AM CST SAT DEC 26 2009/
UPDATE...
REDUCING POPS IN THE SOUTHEAST.
DISCUSSION...
REGIONAL RADARS SHOW ANY PRECIP IS CONFINED TO COASTAL SECTIONS OF
DEEP SOUTH TEXAS. EARLY LOOK AT MODEL DATA SHOWS PRECIP STAYING
SOUTH AND EAST OF OUR CWA. SO...HAVE REDUCED POPS IN OUR
SOUTHEASTERN COUNTIES AND REMOVED ALL WEATHER. HAVE MADE MINOR
ADJUSTMENTS TO TEMP...DEW POINT...AND WIND GRIDS TO ACCOUNT FOR
HOURLY TRENDS. THESE CHANGES WILL NOT AFFECT ZONE FORECASTS.
PREV DISCUSSION... /ISSUED 522 AM CST SAT DEC 26 2009/
DISCUSSION...
SEE AVIATION FOR THE 12Z TAF DISCUSSION.
AVIATION...
VFR CONDITIONS WILL PREVAIL WITH CIRRIFORM CLOUDS STREAMING EASTWARD
ACROSS SOUTH CENTRAL TEXAS. VFR CIGS AOB 10K FT WITH PATCHY LIGHT
RAIN WILL OCCUR LATER TODAY SOUTHEAST OF THE I-35 TERMINALS. SFC WINDS
TODAY WILL BE EAST TO SOUTHEAST AT LESS THAN 10 KTS...BECOMING LIGHT
AND VARIABLE TONIGHT.
PREV DISCUSSION... /ISSUED 440 AM CST SAT DEC 26 2009/
DISCUSSION...
A WEAK UPPER LEVEL SHORTWAVE WILL MOVE ACROSS SOUTHERN TEXAS LATER
TODAY INTO TONIGHT. A SURFACE LOW/TROUGH DEVELOPS OFF THE TEXAS
COAST TO GENERATE WEAK ISENTROPIC LIFT INTO AREAS OF SOUTH CENTRAL
TEXAS SOUTHEAST OF THE I-35 CORRIDOR. MOISTURE IS SUFFICIENT TO
MAINTAIN SLIGHT CHANCE POPS FOR AREAS NEAR THE COASTAL PLAINS. THE
SYSTEM MOVES OFF TO THE EAST TONIGHT ALLOWING FOR ANOTHER SURGE OF
SURFACE HIGH PRESSURE WHILE AN UPPER LEVEL RIDGE BUILDS OVER THE
AREA. MOSTLY CLEAR SKIES, LOW DEWPOINTS, AND LIGHT WINDS MAKE FOR
NEARLY FAVORABLE CONDITIONS FOR BELOW AVERAGE TEMPERATURES TONIGHT
AND SUNDAY NIGHT. ANOTHER UPPER TROUGH MOVES ACROSS THE AREA
TUESDAY INTO WEDNESDAY DEVELOPING A SURFACE LOW NEAR THE TEXAS
COAST. ISENTROPIC LIFT DEVELOPS MONDAY NIGHT LEADING TO SLIGHT
CHANCE POPS DURING THE OVERNIGHT HOURS. LARGE SCALE LIFT INCREASES
ON TUESDAY GENERATING HIGH CHANCE TO LIKELY POPS TUESDAY INTO
TUESDAY NIGHT, HOWEVER THEY MAY EVENTUALLY RAISED TO CATEGORICAL.
MODEL SOUNDINGS SUGGEST A BRIEF POSSIBILITY THAT THERE MAY BE SOME
SLEET MIXED IN AS RAINS BEGIN, HOWEVER HAVE LEFT MENTION OUT AS
TOO UNCERTAIN. THE RAINS END FROM WEST TO EAST ON WEDNESDAY AS THE
UPPER TROUGH AND SURFACE LOW MOVE OFF TO THE EAST. THE CLOUDS AND
RAIN KEEP TEMPERATURES RANGES SMALL TUESDAY AND WEDNESDAY. A THIRD
TROUGH MOVES THROUGH ON THURSDAY BRINGING SLIGHT CHANCE POPS TO
THE EASTERN AREAS. THEN A DRY NORTHWESTERLY FLOW PREVAILS FRIDAY.
AS FOR TEMPERATURES, HAVE GONE BELOW GUIDANCE FOR LOWS TONIGHT AND
SUNDAY DUE MOSTLY CLEAR SKIES, LIGHTER WINDS, AND LOW DEWPOINTS.
HAVE GONE BELOW GUIDANCE FOR HIGHS TUESDAY AND WEDNESDAY DUE TO
CLOUDS AND RAIN. HAVE GONE BELOW GUIDANCE FOR LOWS THURSDAY NIGHT
AND HIGHS FRIDAY AS ECMWF SHOWS A COLDER AIRMASS THAN THE GFS.
OTHERWISE, HAVE GONE NEAR GUIDANCE.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 53 33 59 34 54 / - - - - -
AUSTIN BERGSTROM INTL AIRPORT 54 28 58 28 53 / - - - - -
NEW BRAUNFELS MUNI AIRPORT 53 31 60 31 55 / - - - - -
BURNET MUNI AIRPORT 53 31 53 31 50 / - - - - -
DEL RIO INTL AIRPORT 58 35 60 38 52 / - - - - -
GEORGETOWN MUNI AIRPORT 53 31 55 29 51 / - - - - -
HONDO MUNI AIRPORT 55 30 60 32 55 / - - - - -
SAN MARCOS MUNI AIRPORT 53 31 58 31 54 / - - - - -
LA GRANGE - FAYETTE REGIONAL 56 34 56 31 53 / 10 10 - - -
SAN ANTONIO INTL AIRPORT 55 33 60 33 55 / - - - - -
STINSON MUNI AIRPORT 55 33 61 33 56 / - - - - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/11/PM
