FXUS64 KCRP 231746 AAD
AFDCRP
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE CORPUS CHRISTI TX
1146 AM CST WED DEC 23 2009
.DISCUSSION...UPDATED TO INCLUDE 18Z AVIATION DISCUSSION.
&&
.AVIATION...VFR TO MVFR CONDITIONS THIS MORNING WILL IMPROVE TO
MOSTLY VFR THIS AFTERNOON. COLD FRONT WILL THEN MOVE IN THURSDAY
BY 03Z OUT WEST AND SWEEP EAST/SOUTHEASTWARD TOWARD THE COAST.
BETWEEN 07-12Z THE FRONT WILL MOVE THROUGH KALI...KCRP AND KVCT.
SHOWERS AHEAD OF THE FRONT WILL INCREASE AS THE BOUNDARY
APPROACHES TERMINAL SITES...MAINLY ALONG AND EAST OF HIGHWAY 281.
MODERATE SOUTHERLY WINDS WILL SHIFT NORTHWEST AND RAPIDLY
INCREASE BEHIND THE FRONTAL PASSAGE AS SHOWERS MOVE OFFSHORE.
&&
.PREV DISCUSSION... /ISSUED 1018 AM CST WED DEC 23 2009/
DISCUSSION...MADE A FEW MINOR ADJUSTMENTS TO THE ONGOING FORECAST
AS ISOLATED SHOWERS CONTINUE OVER THE EASTERN PORTION OF OUR CWA
AND COASTAL WATERS. OVERALL...LOOKS LIKE TODAY WILL BE
UNSEASONABLY WARM AS WARM AIR ADVECTION CONTINUES OVER THE REGION.
LOOKS LIKE BEST SHOT OF RAINFALL WILL BE TONIGHT AS THE FRONT
APPROACHES. WILL MONITOR THE LATEST GUIDANCE FOR THE AFTERNOON
FORECAST PACKAGE ON CHANCES FOR THUNDERSTORMS. UPDATED PRODUCTS
OUT SHORTLY.
PREV DISCUSSION... /ISSUED 535 AM CST WED DEC 23 2009/
DISCUSSION...UPDATED AVIATION DISCUSSION.
AVIATION...STRONG LOW LEVEL JET PRODUCING LLWS THIS
MORNING...WITH 88D WIND PROFILES SHOWING 40KT SOUTHERLY FLOW JUST
OFF THE SURFACE. SURFACE FRONT FORECAST TO MOVE THROUGH TERMINALS
THIS EVENING AND OVERNIGHT...WITH GUSTY NORTHWEST WINDS
IMMEDIATELY BEHIND THE FRONT. SHOWERS EXPECTED AROUND FRONTAL
PASSAGE...WITH PERHAPS ENOUGH FAVORABLE DYNAMICS ALOFT TO TRIGGER
A FEW THUNDERSTORMS AS WELL. WINDS TO DECREASE FROM WEST TO EAST
ACROSS THE AREA AT AND JUST BEYOND THE END OF THE TAF PERIOD AS
THE FRONT SWEEPS OUT OF THE AREA.
PREV DISCUSSION... /ISSUED 500 AM CST WED DEC 23 2009/
SHORT TERM (TODAY THROUGH THURSDAY)...MORE SOUPY WEATHER IS ON
TAP FOR THE COASTAL BEND TODAY. A FEW STREAMER SHOWERS WILL FALL OVER
FAR NORTHEAST COUNTIES...PRODUCING MINIMAL AMOUNTS OF RAIN. WINDS
WILL AGAIN PICK UP AND BECOME GUSTY THIS AFTERNOON.
THE LATEST IN THE SERIES OF COLD FRONTS WILL PUSH THROUGH THE
COASTAL BEND TONIGHT. EXPECT THE FRONT THROUGH THE BRUSH COUNTRY
DURING THE EVENING...AND COASTAL AREAS NEAR OR AFTER MIDNIGHT.
FAVORABLE DYNAMICS ASSOCIATED WITH AN UPPER LOW PUSHING ACROSS
NORTHERN TEXAS WILL INCREASE CHANCES FOR PRECIPITATION ALONG THE
FRONT. MARGINAL INSTABILITY COULD PRODUCE A FEW THUNDERSTORMS AS
THE SYSTEM MOVES THROUGH.
COLDER AIR MOVES IN QUICKLY BEHIND THE FRONT...STUNTING RAIN
CHANCES BY MORNING AND HOLDING HIGH TEMPERATURES TEN DEGREES OR SO
BELOW WEDNESDAY HIGHS.
LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...FORECAST UNCERTAINTIES
IN RAIN CHANCES AND TEMPERATURE EXTREMES REMAIN LARGER THAN ONE
WOULD LIKE...AS SOME MODEL DISCREPANCIES FROM RUN TO RUN CONTINUE...
WITH GFS OFTEN CHANGING ITS MIND ON HOW FAR NORTH BEST MOISTURE
MOVES...STRENGTH OF COASTAL TROUGH AND HOW FAR SOUTH COLD DOME OF
HIGH PRESSURE WILL MOVE INTO TEXAS. GOOD BET THAT MOISTURE AND
CLOUDS WILL INCREASE ON FRIDAY...AFTER THAT UNCERTAINTY INCREASES.
COASTAL TROUGH DEVELOPS FRIDAY NIGHT...BUT NOW 00Z GFS RUN KEEPS
BETTER MOISTURE A BIT FARTHER SOUTH THAN PREVIOUS RUNS. SOME JET
DYNAMICS ALOFT MAY HELP...BUT ISENTROPIC PATTERN NOT REALLY STRONG.
IN SHORT...WILL MAINTAIN SIMILAR POPS SOUTHERN AREAS BUT TRIM THEM
NORTH SO THAT NO RAIN IS MENTIONED IN THE VICTORIA AREA AND MOST OF
THE NORTHERN TIER OF COUNTIES. ISENTROPIC UPGLIDE PATTERN CONTINUES
ON SUNDAY WITH COASTAL TROUGH REMAINING (GFS AGAIN STRONGEST). NO
UPPER SUPPORT AND BEST MOISTURE REMAINS SOUTH...SO WILL RELUCTANTLY
KEEP JUST A SLIGHT CHANCE FOR RAIN AGAIN MOST LOCATIONS SINCE MODEL
CONSENSUS COULD RETURN TO WETTER SCENARIO. MOISTURE IMPROVES BY
MONDAY AS COASTAL TROUGH REMAINS...AND ISENTROPIC PATTERN IMPROVES
AS UPPER LEVEL SYSTEM APPROACHES. APPEARS BEST UPPER DYNAMICS WILL
BE TUESDAY...BUT COULD BEGIN AS EARLY AS MONDAY NIGHT. 00Z GFS
SLOWEST OF THEM ALL...AND WILL LEAN MORE TOWARD THE OTHER MODELS
BRINGING EFFECTS OF SYSTEM INTO THE AREA MONDAY NIGHT...AND KEEPING
RAIN IN THE FORECAST THROUGH THE DAY ON WEDNESDAY...IN CASE GFS IS
RIGHT BUT ALSO BECAUSE SOME ENERGY REMAINS FROM ECMWF AND CANADIAN
AS WELL FOR WEDNESDAY MORNING.
WITH RESPECT TO TEMPERATURES...GFS IS NOW GOING BACK TO A COLD
SCENARIO (STILL LIQUID THOUGH AS 850MB TEMPS REMAIN WELL ABOVE 0C IN
CWFA). GFS BRINGS RIDGE WELL INTO SOUTH TEXAS ON SATURDAY...AND
CONTINUES IT THROUGH TUESDAY. ECMWF IS AGAIN WARMER KEEPING MAIN
PART OF HIGH TO THE NORTHEAST. GFS MAY BE OVER-DOING THINGS FOR TOO
LONG...BUT WILL GENERALLY LEAN MORE TOWARD THE GFS FOR THE WEEKEND
WITH THE GOOD NORTHERLY FETCH ALOFT...THEN WARM THINGS UP A BIT MORE
FOR MONDAY AND TUESDAY WITH THE UPPER TROUGH APPROACHING. MODELS ARE
TENDING TO KEEP THINGS MORE STABLE THAN BEFORE...BUT WILL MAINTAIN
THUNDER FOR TUESDAY SINCE UPPER SYSTEM WILL BE POTENT ENOUGH (AND
MODELS MAY GO BACK TO WARMER PATTERN). IN SHORT...UNCERTAINTIES
REMAIN AND ADJUSTMENTS TO THIS PACKAGE WILL LIKELY HAVE TO BE MADE
DOWN THE ROAD AS ULTIMATE SCENARIO BECOMES MORE APPARENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 76 54 68 38 54 / 10 40 10 0 10
VICTORIA 75 52 64 34 53 / 40 60 10 0 10
LAREDO 81 51 71 42 57 / 10 10 0 0 10
ALICE 81 50 69 36 56 / 10 30 10 0 10
ROCKPORT 72 55 68 38 54 / 30 50 10 0 10
COTULLA 77 45 68 36 56 / 10 20 0 0 10
KINGSVILLE 80 54 70 36 56 / 10 30 10 0 10
NAVY CORPUS 75 56 68 42 54 / 20 50 10 0 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 4 AM CST FRIDAY FOR THE FOLLOWING
ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60
NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL
FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY FROM 2 AM TO 4 PM CST THURSDAY FOR THE
FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT
ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT
O'CONNOR.
SMALL CRAFT ADVISORY UNTIL 10 PM CST THURSDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT
20 NM...COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP
CHANNEL OUT 20 NM.
&&
$$
RG/82...UPDATE/AVIATION
