000
FXUS64 KHGX 201153
AFDHGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
653 AM CDT SAT MAR 20 2010
.DISCUSSION...
12Z TAF DISCUSSION BELOW.
&&
.AVIATION...
LOOKING AT THE REGIONAL RADAR...SQUALL LINE IN C TX WILL BE THE
PROBLEM FOR SE TX TERMINALS FOR THE NEXT 6-12 HRS. LINE OF STORMS
IS MOVING QUICKLY AT AROUND 30-35KTS JUST AHEAD OF THE COLD
FRONT. TAFS WERE ADJUSTED FOR THIS SPEED WHICH BRINGS THE STORMS
INTO KCLL AROUND 13-14Z AND KUTS/KCXO BY 14-15Z. SQUALL LINE
SHOULD THEN REACH KIAH AND HOUSTON TERMINALS AROUND 15-16Z AND
THEN THE GULF COAST AROUND 17-18Z. RIGHT NOW MAIN THREAT WITH
STORMS WILL BE LIGHTNING...HEAVY RAINFALL AND VERY GUSTY WINDS.
TAFS HAVE AN INITIAL 20G30KT BUT WOULD NOT BE SURPRISED AT ALL TO
SEE 30G40KT AS THE LINE MOVES THROUGH AS REPORTED BY KACT AND
KTPL RECENTLY. TAFS WILL BE MONITORED AND POSSIBLY UPDATED IF
OTHER TERMINALS REPORT SIMILAR WIND GUSTS WITH THE STORMS. WINDS
DO SHIFT TO 340 AND THEN TURN MORE TO 320 DURING THE LATE
AFTERNOON AND NIGHT. WINDS MAY SLACK OFF A LITTLE BIT OVERNIGHT
BUT REMAIN STRONG ALONG THE COAST. SUNDAY LOOKS TO BE QUITE WINDY
AS WELL. OVERALL SUSPECT WINDS ARE MORE LIKELY TO REMAIN CLOSER TO
15KTS OVERNIGHT WITH SOME GUSTS MIXED IN EVEN THOUGH GUIDANCE
SUGGEST WINDS LESS THAN THAT. CEILINGS WILL BE SLOW TO RECOVER IN
WAKE OF THE FRONT. WILL HOLD ONTO MVFR CIGS THROUGH ABOUT 06Z
TONIGHT FOR MOST OF THE AREA AND THEN HIGH CLOUDS AFTER THAT.
&&
.PREV DISCUSSION... /ISSUED 618 AM CDT SAT MAR 20 2010/
DISCUSSION...
WARM SOUTHEASTERLY FLOW IN PLACE AHEAD OF THE ONCOMING STORMS.
LINE OF STORMS NEAR A TRL-INJ-GOP-BMQ-ERV LINE AT 520 AM MOVING
EAST OR ESE AT 23-30 KTS. SOUTHERN END OF THE FRONTAL BOUNDARY HAS
PLENTY OF LIGHTNING AND IT WILL CONTINUE TO MOVE INTO AN UNSTABLE
AIRMASS THOUGH ONLY MARGINALLY. HAVE CONTINUED THE MENTION OF TSRA
AND HAVE INCREASED POPS ESPECIALLY IN THE SOUTHWEST. CAPE OF LESS
THAN 400 MAINLY ACROSS THE I-10 CORRIDOR SOUTHWARD. WIDESPREAD
RAINFALL OF 1/2" LOOKS LIKELY TODAY WITH THE SOUTHERN AREAS
RECEIVING AMOUNTS OF 1 TO 2 INCHES. STRONG GUSTY WINDS ALSO
POSSIBLE WITH THE STRONGER STORMS IN THE SOUTH. NEXT ISSUE IS THE
CAA IN THE WAKE OF THE FRONT. STRONG NORTHWEST WINDS SHOULD
DEVELOP AND DROP TEMPERATURES QUICKLY. HIGHS IN THE CLL AREA
SHOULD OCCUR THIS MORNING BEFORE 10 AM THEN FALL INTO THE 50S.
HIGH TEMPERATURES ACROSS THE HOUSTON AREA AND WEST TO AROUND SEALY
AND NORTH TO HUNTSVILLE WILL BE VERY CHALLENGING TO GET RIGHT AS
TIMING OF FRONTAL PASSAGE COULD SEVERELY HAMPER THE RISE IF FRONT
SPEEDS UP FROM CURRENT FORECAST. HAVE GREATER CONFIDENCE IN HIGH
TEMPS FOR AREAS TO THE EAST AND SOUTH OF HOUSTON WHERE THE WAA
WILL PERSIST LONGER. EXPECT THE STORMS TO DEPART THE AREA BY 23Z.
A FEW ISOLATED SHOWERS MAY LINGER OVER THE COASTAL WATERS AND
EASTERNMOST COUNTIES THROUGH 7 OR 8 PM. STRONG CAA WILL CRANK UP
THE WINDS AND HAVE ISSUED A TWO PART WIND ADVISORY...PART ONE IS
FOR THE AREAS ROUGHLY ALONG AND SOUTH OF THE HIGHWAY 50 CORRIDOR
WHERE SUSTAINED NORTHWEST WINDS OF 20 KNOTS WITH HIGHER GUSTS WILL
BE DEVELOPING THIS AFTERNOON AND CONTINUE THROUGH THE NIGHT THOUGH
THE INLAND COUNTIES WILL LIKELY LOSE SOME OF THE GUSTINESS. PART
TWO OF THE ADVISORY WILL BE FOR SUNDAY AS DEEP STRONG
NORTHWESTERLY FLOW WILL MIX DOWN AS THE UPPER LOW MOVES VERY
SLOWLY EAST AND BLANKETS THE AREA WITH STRONG AND GUSTY WINDS.
WINDS WILL EVENTUALLY RELAX SUNDAY NIGHT AND SHOULD BE THE COLDEST
NIGHT AS SKIES WILL HAVE FINALLY CLEARED OF THE WRAP AROUND CLOUDS
AND DECOUPLE. 30S SHOULD BE FAIRLY WIDESPREAD AND DO HAVE SOME
CONCERN THAT THE FAR NORTHERN COUNTIES COULD COME CLOSE TO THE
FREEZING MARK. HIGH PRESSURE AND DRY WEATHER SHOULD BE ON TAP
SATURDAY NIGHT THROUGH TUESDAY WITH RETURN FLOW AND A WARM FRONT
ARRIVING WEDNESDAY. TEMPERATURES SHOULD BE BACK UP TO NORMAL
WEDNESDAY MORNING. RAIN CHANCES INCREASING THURSDAY WITH A PACIFIC
COLD FRONT.
45
MARINE...
WINDS HAVE COME UP TO 15-20KTS IN THE OFFSHORE WATERS OUT 20-60NM
OFF THE UPPER TX COAST. SEAS HAVE RESPONDED WITH A MODEST BUILD TO
6FT AT THE 019 BUOY. FORECAST WILL KEEP SCEC FOR OFFSHORE WATERS
UNTIL 15Z. COLD FRONT NOW IN W C TX LOOKS TO BE ON TRACK TO PUSH
OFF THE COAST THIS EVENING AND WINDS SHOULD DECREASE AHEAD OF THE
FRONT HENCE ENDING THE SCEC. COLD FRONT IS STILL EXPECTED TO BE
QUITE STRONG AND WILL KEEP SCA/GALE WARNING IN PLACE. STILL SOME
QUESTION AS TO HOW LONG SCA/GALE CONDITIONS WILL LAST ON SUNDAY.
SUSPECT THAT GALE/SCA WILL NEED SOME MINOR TWEAKS. A FAIRLY STOUT
PRESSURE GRADIENT WILL PERSIST INTO SUN EVENING SO SCA CONDITIONS
MAY LAST AT LEAST THAT LONG. WINDS AND SEAS WILL QUICKLY DROP OFF
MON INTO TUE AS HIGH PRESSURE BUILDS OVER THE TX GULF COAST.
ONSHORE FLOW DEVELOPS ONCE AGAIN FOR THE MIDDLE OF THE COMING WEEK.
ANOTHER FRONT MAY PUSH OFF THE COAST FOR THIS COMING THU/FRI.
39
AVIATION...
09Z TAF UPDATES INCLUDE SOME ADJUSTMENT FOR THE FRONTAL PASSAGE AND
CONVECTION ALONG/AHEAD OF THE FRONT. LIGHTNING DATA SHOWING SOME
LIGHTNING WITH STORMS IN W C TX SO WILL KEEP MENTION OF THUNDER FOR
THE TAFS. THE MAIN CONCERN WILL BE THE ABRUPT WIND SHIFT WITH THE
FRONTAL PASSAGE. WINDS WILL BE STRONG BEHIND THE FRONT AND LIKELY
PERSIST THROUGH SUNDAY.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 60 34 55 34 67 / 100 0 0 0 0
HOUSTON (IAH) 67 35 56 35 67 / 90 10 0 0 0
GALVESTON (GLS) 71 46 57 46 63 / 90 20 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...WIND ADVISORY FROM 10 AM TO 7 PM CDT SUNDAY FOR THE FOLLOWING
ZONES: AUSTIN...BRAZOS...BURLESON...COLORADO...GRIMES...
HOUSTON...LIBERTY...MADISON...MONTGOMERY...POLK...SAN
JACINTO...TRINITY...WALKER...WALLER...WASHINGTON.
WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM CDT SUNDAY FOR
THE FOLLOWING ZONES: BRAZORIA...CHAMBERS...FORT BEND...
GALVESTON...HARRIS...JACKSON...MATAGORDA...WHARTON.
GM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM CDT SUNDAY
FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20
NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM CDT THIS
EVENING FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
HIGH ISLAND TO FREEPORT 20 TO 60 NM.
SMALL CRAFT ADVISORY FROM 10 AM SUNDAY TO 1 AM CDT MONDAY FOR
THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA
SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 10 AM CDT THIS MORNING
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT 20 TO 60 NM.
GALE WARNING FROM 7 PM THIS EVENING TO 10 AM CDT SUNDAY FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...45
AVIATION/MARINE...39
