FXUS64 KEWX 110540
AFDEWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1140 PM CST THU DEC 10 2009
.DISCUSSION...
SEE AVIATION SECTION.
&&
.AVIATION...
FORECAST REASONING IS ABOUT THE SAME AS THE PREVIOUS PACKAGE...BUT
TIMING HAS CHANGED. STILL LOOKING FOR WARM MOIST AIR TO MOVE OVER
THE TOP OF LOW LEVEL COLD DOME AND PRODUCE MVFR TO IFR CIGS AND
LIGHT RAIN AND FOG. HOWEVER...HAVE PUSHED BACK ONSET TO AROUND 18Z
FOR CIGS AND 00Z FOR PRECIP. THERE IS A LOW PROBABILITY OF PRECIP
BEGINNING BETWEEN 21Z AND 00Z.
PRECIP IS NOT LIKELY AT DRT. YOU CAN EXPECT ONLY MVFR CIGS FOR THE
NEXT 24 HOURS.
&&
.PREV DISCUSSION... /ISSUED 917 PM CST THU DEC 10 2009/
UPDATE...
00Z SOUNDINGS INDICATE MOIST SLY WINDS AROUND 2K FEET OVERRUNNING
THE COOL AIRMASS AT THE SURFACE. BOTH DFX AND EWX RADAR SHOWING
MOISTURE STREAMING EASTWARD ACROSS THE AREA AT 16-20K FEET. THIS
WILL RESULT IN DETERIORATING CONDITIONS LATE TONIGHT INTO FRIDAY AS
LIGHT DRIZZLE/RAIN DEVELOPS OVER THE COASTAL PLAINS AND SPREADS
NORTH AND WEST. BURNETT CURRENTLY AT 35 DEGREES AND MAY DROP A
DEGREE OR TWO TO NEAR FREEZING TONIGHT...HOWEVER BY THE TIME
DRIZZLE BEGINS TEMPERATURES WILL BE RISING AND WELL ABOVE
FREEZING. NO CHANGES NEEDED TO ONGOING FORECAST.
PREV DISCUSSION... /ISSUED 359 PM CST THU DEC 10 2009/
DISCUSSION...
COLD AIR CONTINUES TO FILTER SOUTH INTO CENTRAL TX FROM THE
NORTHEAST WITH A STREAM OF HIGH CLOUDS HELPING TO MINIMIZE MIXING.
THIS WILL KEEP COOL TEMPS IN PLACE FOR FRIDAY INTO EARLY SATURDAY
AS A WEAK DISTURBANCE MOVES ACROSS AND GENERATES A LIGHT
OVERRUNNING PATTERN. THE BEST CHANCE OF RAIN WILL BE NEAR THE
COAST WHERE MOISTURE AND ISENTROPIC LIFT IS BEST. RAINFALL AMOUNTS
SHOULD BE GENERALLY LESS THAN ONE-QUARTER INCH. LOW CLOUDS DRIZZLE
AND FOG SHOULD LINGER INTO FRIDAY NIGHT WITH PATCHY FOG POSSIBLE
SATURDAY MORNING. THE SUBSIDENCE PATTERN BEHIND THE SHORTWAVE
SHOULD BE WEAK SO THE SUN MAY NOT COME OUT FOR LONG ON SUNDAY.
STILL THE MODELS ARE TRENDING FOR PLEASANT WARMING TO AROUND 70 OR
LOWER 70S FOR MOST AREAS. HAVE LEANED A BIT COOLER THAN THE MODELS
HERE AS THE GFS IN PARTICULAR HAS SHOWN A WARM DAYTIME BIAS.
A STRONGER PACIFIC DISTURBANCE IS EXPECTED MONDAY INTO EARLY
TUESDAY THAT SHOULD BRING THE NEXT DOSE OF COLD AIR. THE COLD AIR
OVER THE CENTRAL US SHOULD MODIFY OVER THE WEEKEND...SO THE
AIRMASS WITH THIS FRONT SHOULD BE A BIT LESS DENSE THAN AIRMASS
CURRENTLY SETTLED OVER TX. A WEAKER PATTERN OF ZONAL FLOW ALOFT
SHOULD ALLOW FOR FEWER CLOUDS AND BETTER DAYTIME AIR MODIFICATION.
EXPECT GOOD DIURNAL RANGES FOR LATE NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 38 45 43 60 47 / 10 40 50 - 10
AUSTIN BERGSTROM INTL AIRPORT 34 45 42 60 44 / 10 50 50 10 10
NEW BRAUNFELS MUNI AIRPORT 38 47 43 60 45 / 10 50 50 - -
BURNET MUNI AIRPORT 34 45 40 60 45 / - 30 40 - -
DEL RIO INTL AIRPORT 42 55 46 66 46 / - 10 10 - -
GEORGETOWN MUNI AIRPORT 34 45 41 59 45 / 10 40 50 10 10
HONDO MUNI AIRPORT 39 48 43 63 44 / 10 30 30 - -
SAN MARCOS MUNI AIRPORT 37 46 43 59 44 / 10 50 50 - 10
LA GRANGE - FAYETTE REGIONAL 37 47 44 56 46 / 20 70 60 10 10
SAN ANTONIO INTL AIRPORT 39 47 44 61 46 / 10 40 50 - -
STINSON MUNI AIRPORT 40 48 44 62 45 / 10 50 50 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01/05
