Severe Thunderstorm Warning 63, NWS Austin/San Antonio, TX

SOUTH CENTRAL TEXAS FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1020 PM CDT FRI MAY 16 2003

UPDATED AGAIN TO ADD POPS TO ANOTHER TIER OF COUNTIES AS BACK
BUILDING CONTINUES.

930 DISCUSSION...
ISSUED QUICK UPDATE TO ADD CHANCE POPS AND POSSIBLE SEVERE
THUNDERSTORMS TO EASTERN MOST-COUNTIES AS LINE OF THUNDERSTORMS
WITH FRONT BACK BUILDS TOWARD OUR CWA.  COULD BE AN INTERESTING
INTERACTION WITH THE SEA BREEZE.

745 PM DISCUSSION...
WELL...ANOTHER SYSTEM IS A DUD AS FAR AS BRINGING RAIN
TO THE CWA. COOL FRONT HAS MADE IT INTO THE HILL COUNTRY AND DRT.
FOR THIS UPDATE WILL ONLY MAKE SOME ADJUSTMENTS TO WINDS CONSIDERING
LOCATION OF THE FRONT WHICH WILL MOVE THROUGH REGION OVER NIGHT.

3/2/DC

PREVIOUS DISCUSSION...
DESPITE RECORD SETTING WARMTH, THE DRY WEATHER CONTINUES. AFTERNOON
CUMULUS FIELDS STILL LOOK SUPPRESSED ON SATELLITE VIS AND OUT THE
WINDOW SO WILL KEEP POPS OUT OF THE ZONES FOR THIS EVENING AND
CANCEL THE RFW ISSUED EARLIER. SATELLITE WV IMAGERY INDICATES THE
DRIEST PORTION OF THE DRY SLOT CONVENIENTLY MOVING OVER SOUTH
CENTRAL TEXAS DURING THE TIME OF MAXIMUM HEATING TO SUPPRESS ANY
HOPE OF CONVECTION THAT WAS OFFERED IN THE LATE MORNING UPDATE. A
HEALTHY NORTHWEST FLOW PATTERN WILL REMAIN FOR ANOTHER DAY OR SO,
BUT NOT BENEFIT FROM THE APPROACHING MOISTURE PLUME FROM THE
SUBTROPICAL PACIFIC ACCORDING TO MODELS. THERE WOULD APPEAR TO BE A
SLIGHT OPPORTUNITY FOR CONVECTION TO FIRE OVER THE HIGHER ELEVATIONS
OF NEW MEXICO AND MOVE IN THIS NW FLOW IF THE PACIFIC PLUME
CONTRIBUTED INSTABILITY TO COMPLEMENT THE MOIST AIR ADVECTION
BLOWING UPSLOPE FROM THE CENTRAL PLAINS HENCE WILL KEEP A FEW 5
PERCENTS IN THE CCF THROUGH TOMORROW NIGHT, BUT NOT MENTION ANY POPS
IN THE ZONES. BY SATURDAY NIGHT THE UPPER RIDGE WILL STEEPEN OVER
THE AREA WITH ONLY LIGHT ONSHORE FLOW KEEPING MORNING LOWS A FEW
DEGREES COOLER THEN THEY HAVE BEEN IN THE PAST WEEK.

THE NEXT POSSIBLE DISTURBANCE OVER THE CENTRAL US IS EXPECTED BY THE
MEDIUM RANGE MODELS TO PRODUCE A BACKDOOR COLD FRONT AND CHANCE OF
RAIN BY FRIDAY. WILL IGNORE FOR NOW AS THE MODEL PERFORMANCE FOR
EXTENDED PERIODS ON A LOW IN THIS PART OF THE US WAS OVERDONE THE
PAST COUPLE TIMES.

TEMPS WILL REMAIN ABOVE CLIMATOLOGICAL NORMS THROUGH THE PERIOD AS
CLIMATOLOGY TENDS TO BE SKEWED TOWARD THE RANDOM CLOUDY AND COOLER
PERIODS THAT OCCUR ONCE EVERY 3-5 YEARS. UNLIKE THE UNUSUALLY WARM
DAY TODAY, THE FORECAST IS FOR A TYPICAL DRY MAY PATTERN. THE LATER
PERIODS OF THE EUROPEAN AND GFS MODELS SHOW HINTS OF THE TRANSITION
INTO THE JUNE SEABREEZE PATTERN WITH THE SUBTROPICAL RIDGE PUSHING
NORTH INTO THE DESERT SW AND WEST TX. THUS OUR NEXT HOPE FOR DROUGHT
RELIEF MAY COME FROM THE GULF ABOUT A WEEK FROM NOW.

PRELIMINARY NUMBERS...
AUS 066/090/066/094/071 ---00
DRT 069/097/072/101/074 0-000
SAT 069/092/070/095/072 ---00

.EWX...NONE
18/26

TXZ171>173-183>194-202>209-217>225-228-171100-

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1155 AM CDT FRI MAY 16 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH CENTRAL TEXAS.

.DAY ONE...TODAY

...RED FLAG WARNING FOR RIO GRANDE PLAINS THIS AFTERNOON...

DAYTIME HEATING...MOIST GULF AIR...AND THE DRYLINE ARE EXPECTED TO
PRODUCE ISOLATED SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING.
THE MAIN THREAT AREA IS ALONG AND EAST OF A LINE FROM GEORGETOWN TO
HONDO TO CRYSTAL CITY. THE MAIN SEVERE THREATS ARE LARGE HAIL AND
DAMAGING WIND. THE PRIMARY RISK TIME IS FROM 3 TO 8 PM.

IN ADDITION...VERY DRY AIR...GUSTY WINDS...AND THE POSSIBILITY OF
DRY LIGHTNING HAVE RESULTED IN A RED FLAG WARNING FOR FIRE ACTIVITY
BEING POSTED FOR THE RIO GRANDE PLAINS. FIRE OFFICIALS SHOULD REFER
TO THE REGULAR FIRE WEATHER FORECAST FOR MORE DETAILS.

.DAYS TWO THROUGH SEVEN...

HOT AND DRY CONDITIONS ARE EXPECTED THROUGH THE MIDDLE OF NEXT
WEEK...WITH THE EXCEPTION OF ISOLATED EVENING AND NIGHTTIME
THUNDERSTORMS OVER THE RIO GRANDE PLAINS.

SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON AT LOCATIONS ALONG
AND EAST OF INTERSTATE 35.