695
FXUS64 KEWX 201822 AAA
AFDEWX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1222 PM CST THU FEB 20 2025
..NEW UPDATE, AVIATION
UPDATE
ISSUED AT 1209 PM CST THU FEB 20 2025
EARLIER UPDATES WERE MADE TO THE FORECAST TO INCREASE CLOUD COVER AND
DECREASE TEMPERATURES ACROSS THE WESTERN AND CENTRAL PORTIONS OF THE
REGION. CLOUDS REMAIN STUBBORN OUT WEST ALONG THE RIO GRANDE AND
MOST MODELS ARE STRUGGLING TO RESOLVE THESE CLOUDS. LEANED TOWARD THE
NAM12 IN THE SHORT TERM WITH RESPECT TO CLOUD COVER.
SHORT TERM
(TODAY THROUGH FRIDAY)
ISSUED AT 155 AM CST THU FEB 20 2025
KEY MESSAGES:
- ARCTIC COLD CONTINUES IN THE SHORT TERM WITH DANGEROUS WIND CHILLS THIS
MORNING AND HARD FREEZES BOTH MORNINGS.
- EXTREME COLD WARNING IS IN EFFECT FOR THE NORTHERN RIO GRANDE, EDWARDS
PLATEAU, HILL COUNTRY, I-35 CORRIDOR, AND COASTAL PLAINS. COLD
WEATHER ADVISORY IS IN EFFECT FOR THE SOUTHERN RIO GRANDE AND
WINTER GARDEN. THESE REMAIN IN EFFECT THROUGH NOON CST TODAY.
- POTENTIAL FOR VERY LIGHT FREEZING DRIZZLE FRIDAY AFTERNOON.
ARCTIC HIGH PRESSURE REMAINS IN CONTROL. THE STRONGEST SURFACE
PRESSURE GRADIENT IS THIS MORNING WITH NORTHERLY WINDS OF 10 TO 15
MPH AND GUSTS UP TO 25 MPH. THESE WINDS COMBINED WITH TEMPERATURES
IN THE TEENS AND 20S CREATE WIND CHILLS OF ZERO TO 5 EDWARDS PLATEAU
AND HILL COUNTRY, 5 TO 10 I-35 CORRIDOR TO THE COASTAL PLAINS, AND
10 TO 20 WINTER GARDEN. THE EXTREME COLD WARNING FOR THE NORTHERN
RIO GRANDE, EDWARDS PLATEAU, HILL COUNTRY, I-35 CORRIDOR, AND
COASTAL PLAINS AND THE COLD WEATHER ADVISORY FOR THE SOUTHERN RIO
GRANDE AND WINTER GARDEN CONTINUE THROUGH NOON CST TODAY. A WARMER
DAY IS EXPECTED AS CLOUDINESS WILL NOT BE AS EXTENSIVE WITH
TEMPERATURES AND WIND CHILLS RISING OUT OF CRITERIA LEVELS. AS AN
UPPER LEVEL TROUGH APPROACHES FROM THE WEST, A SURFACE TROUGH FORMS
OFF THE TEXAS COAST TONIGHT INTO FRIDAY. WARM, MOIST ADVECTION
DEVELOPS TONIGHT LEADING TO STRENGTHENING ISENTROPIC FORCING ON
FRIDAY. EXTENSIVE CLOUDINESS RETURNS TONIGHT INTO FRIDAY WITH PATCHY
PRECIPITATION DEVELOPING BY THE AFTERNOON. LOW TEMPERATURES TONIGHT
WILL BE WARMER DUE TO THE CLOUDINESS, THOUGH STILL MOSTLY BELOW
FREEZING. HIGH TEMPERATURES ON FRIDAY WILL BE COLDER AGAIN DUE TO THE
CLOUDINESS AND WET BULB EFFECTS AS THE PRECIPITATION DEVELOPS. THE
PRECIPITATION BECOMES FOCUSED MAINLY ALONG THE I-35 CORRIDOR AS THE
LOWER LEVELS SATURATE THERE SOONER. FORECAST SOUNDINGS INDICATE IT
WOULD BE DRIZZLE OR FREEZING DRIZZLE. ANY AMOUNTS WOULD BE VERY LIGHT
AND SHOULD NOT CAUSE ANY IMPACTS.
LONG TERM
(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 155 AM CST THU FEB 20 2025
KEY MESSAGES:
- LOW CHANCE FOR FREEZING RAIN FOR THE HILL COUNTRY AND I-35 FRIDAY NIGHT
INTO SATURDAY MORNING.
- SHOWERS OVER THE COASTAL PLAINS SATURDAY THROUGH SUNDAY MORNING.
- WARM TREND SUNDAY THROUGH THE MIDDLE OF NEXT WEEK.
BY FRIDAY NIGHT, A SLOW-MOVING SURFACE TROUGH IS FORECAST TO LIE
JUST OFF THE SOUTH TEXAS COAST. ALOFT, AN AMPLIFYING UPPER-LEVEL
DISTURBANCE OVER THE SOUTHWESTERN US IS EXPECTED TO SUPPORT THE
DEVELOPMENT OF A 30 KT SOUTHERLY LOW LEVEL JET AT 850MB, FUNNELING
MOISTURE FROM THE COASTAL DISTURBANCE INTO OUR AREA. THIS WILL
ENHANCE THE ASCENT OF AIR ATOP INITIALLY DENSE AND SOMEWHAT DRY COLD
AIR NEAR THE SURFACE. A LOW STRATIFORM CLOUD DECK WILL COVER MUCH OF
THE REGION AND MODEL SOUNDINGS SHOW THIS CLOUD DECK THICKENING
THROUGH THE NIGHT AS THE AIR BENEATH THE CLOUD GRADUALLY MOISTENS
WITH MORE PRECIPITATION EVENTUALLY REACHING THE GROUND. CURRENTLY,
GUIDANCE SUGGESTS THE WESTERN FLANKS OF THE MAIN AXIS OF MOISTURE
TRANSPORT FRIDAY NIGHT INTO SATURDAY MORNING MAY EXTEND INTO THE I-
35 CORRIDOR AND THE HILL COUNTRY WHERE OVERNIGHT TEMPERATURES ARE
CURRENTLY FORECAST TO BOTTOM OUT AROUND 28 TO 33 DEGREES. THUS, THE
RATE OF THIS LOW-LEVEL MOISTENING WILL BE PIVOTAL IN DETERMINING
PRECIPITATION TYPE AND COVERAGE. MEAN SREF ENSEMBLE SOUNDINGS SHOW
AN ABOVE-FREEZING WARM NOSE OVER MOST OF THE CLOUD DECK ALOFT, BUT
WITHIN ABOUT 2000 FT OF THE GROUND, EVAPORATIVE COOLING COULD
INTRODUCE CONDITIONS MORE CONDUCIVE TO FREEZING RAIN. THE LATEST
LREF ENSEMBLE INDICATED THAT THE MOST LIKELY OVERLAP OF SUBFREEZING
WET BULB TEMPERATURES AND PRECIPITATION WAS OVER THE HILL COUNTRY
NEAR THE I-35 CORRIDOR EARLY SATURDAY MORNING. SOME OF THE HIGHER
RESOLUTION MESOSCALE MODELS, WHICH TEND TO OUTPERFORM COARSER MODELS
IN THESE SETUPS, ARE STARTING TO GET IN RANGE OF THIS POTENTIAL
EVENT AND ARE ALSO HINTING AT THIS FREEZING RAIN POTENTIAL FRIDAY
NIGHT AND SATURDAY MORNING. ACKNOWLEDGING THIS GUIDANCE AND GIVEN
THEIR BETTER HANDLING OF PREVIOUS EVENTS, I HAVE INCREASED THE AREA
OF POSSIBLE FREEZING RAIN OVER PARTS OF THE HILL COUNTRY AND I-35
CORRIDOR NORTH OF BEXAR COUNTY, THOUGH OVERALL POPS ARE STILL ONLY
AROUND 30 PERCENT. WE WILL CONTINUE TO MONITOR MESOSCALE TRENDS AS
THIS POTENTIAL EVENT MOVES INTO THE SHORT-RANGE.
PRECIPITATION RATES SATURDAY MORNING, EITHER FREEZING OR LIQUID,
SHOULD BE GENERALLY LIGHT GIVEN THE SHALLOW DEPTH OF CLOUD (BELOW
ABOUT 750MB) AND MODEST ASCENT. TEMPERATURES SHOULD GET INTO THE 40S
SATURDAY AFTERNOON, SO PRECIPITATION TYPES SHOULD EVENTUALLY BE ALL
LIQUID. ONGOING SHOWER ACTIVITY PRIMARILY OVER THE COASTAL PLAINS
MAY STRENGTHEN AND GROW IN COVERAGE SOME SATURDAY AFTERNOON ONWARDS
AS A SHORTWAVE TROUGH APPROACHES. THIS SHORTWAVE HAS TRENDED SLOWER
IN THE LATEST GUIDANCE, SO RAIN SHOWERS LOOK TO PERSIST OVER THE
COASTAL PLAINS INTO SUNDAY MORNING. CURRENT GUIDANCE SUGGESTS
RAINFALL TOTALS GENERALLY ON THE ORDER OF A FEW TENTHS OF AN INCH
OVER THE WEEKEND, BUT THERE MAY BE LOCALLY HEAVIER TOTALS ESPECIALLY
ALONG AND EAST OF HIGHWAY 77 IF SOME MORE ELEVATED INSTABILITY
MATERIALIZES. SHOWER ACTIVITY WILL GENERALLY SHIFT EASTWARDS WITH
TIME IN TANDEM WITH THE SHORTWAVE.
LOWS SUNDAY MORNING ARE CURRENTLY FORECAST TO BE IN THE UPPER 30S
THROUGHOUT SOUTH CENTRAL TEXAS. BY SUNDAY AFTERNOON, THE
AFOREMENTIONED SHORTWAVE TROUGH SHOULD BE EAST OF OUR AREA. THIS
WILL HAVE THE EFFECT OF BOTH MOVING THE COASTAL DISTURBANCE EASTWARD
AND INTRODUCING A DRY, MID-LEVEL NORTHWESTERLY FLOW. THIS WILL CAUSE
CLOUDS TO CLEAR WEST TO EAST AND SET UP A STRING OF SUNNY AND
WARMING AFTERNOONS. LINGERING CLOUDS SUNDAY MAY STILL RESULT IN A
WEST-TO-EAST CONTRAST IN HIGHS WITH UPPER-50S ALONG HIGHWAY 77 TO
THE LOWER 70S ALONG THE RIO GRANDE. THE WARMING TREND LOOKS TO
CONTINUE TO MIDWEEK WITH HIGHS IN THE 70S AND 80S AND LOWS IN THE
40S AND 50S THROUGH WEDNESDAY. A DISTANT SHORTWAVE TROUGH COULD
BRING A DRY COLD FRONT WEDNESDAY OR THURSDAY NEXT WEEK.
AVIATION
(18Z TAFS)
ISSUED AT 1209 PM CST THU FEB 20 2025
STRATUS CLOUDS ACROSS THE RIO GRANDE PLAINS CONTINUE TO SPREAD NORTH
AND EAST INTO THE HILL COUNTRY AND I-35 CORRIDOR EARLY THIS
AFTERNOON. CLOUD BASES ARE EXPECTED TO REMAIN VFR THROUGH MOST OF
TONIGHT, THEN TREND DOWN INTO UPPER END MVFR AROUND SUNRISE AT DRT TO
THE MID-MORNING HOURS ALONG I-35. WINDS REMAIN FROM THE NORTHEAST
ALONG I-35, WITH SOUTHEAST TO EAST WINDS RETURNING TO DRT.
PRELIMINARY POINT TEMPS/POPS
AUSTIN CAMP MABRY 37 26 36 32 / 0 0 0 20
AUSTIN BERGSTROM INTL AIRPORT 38 25 37 31 / 0 0 0 20
NEW BRAUNFELS MUNI AIRPORT 40 27 37 31 / 0 0 0 20
BURNET MUNI AIRPORT 36 21 35 29 / 0 0 0 10
DEL RIO INTL AIRPORT 44 30 46 36 / 0 0 0 0
GEORGETOWN MUNI AIRPORT 36 23 36 31 / 0 0 0 10
HONDO MUNI AIRPORT 43 28 38 32 / 0 0 0 20
SAN MARCOS MUNI AIRPORT 38 26 36 31 / 0 0 0 20
LA GRANGE - FAYETTE REGIONAL 40 26 38 32 / 0 0 0 10
SAN ANTONIO INTL AIRPORT 41 28 37 32 / 0 0 0 20
STINSON MUNI AIRPORT 43 30 38 33 / 0 0 0 20
EWX WATCHES/WARNINGS/ADVISORIES
NONE.
SHORT-TERM...PLATT
LONG-TERM...MMM
AVIATION...PLATT
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