Small Craft Advisory 73, NWS Houston/Galveston, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
541 AM CST SAT JAN 1 2011

.DISCUSSION...
SEE UPDATES FOR AVIATION...FIRE WEATHER AND CLIMATE.

&&

AVIATION...
MVFR CEILINGS WILL LINGER ALONG THE COASTAL SITES THROUGH MID
MORNING BEFORE SCATTERING OUT BY 18Z. OTHERWISE...WINDS WILL BE THE
MAIN ISSUE TODAY. HIGHER WINDS AROUND 1000 FEET ABOVE GROUND LEVEL
WILL MIX DOWN TO THE SURFACE THROUGH ABOUT 15Z AT THE FAR INLAND
SITES AND 18Z AT KLBX. SURFACE WINDS GUSTING TO NEAR 20 KNOTS WILL
BE COMMON EARLY. A GRADUAL DECREASING IN WINDS TO BELOW 15 KNOTS BY
MID AFTERNOON OVER THE INLAND SITES. KGLS SHOULD SEE A DECREASE IN
THE GUSTY WINDS BY 21Z.

40

&&

.FIRE WEATHER...
SURFACE DEW POINTS HAVE CONTINUED TO DROP AND ARE NOW NEAR 10
DEGREES AT CLL. RH VALUES ARE LESS THAN 20 PERCENT OVER THE
NORTHWEST HALF OF THE REGION. WINDS WILL COME UP TO AROUND 15 MPH
THIS MORNING AND THIS AREA HAS NOT RECEIVED MUCH IN THE WAY OF
RAIN. WE ARE REEVALUATING...BUT FEEL A RED FLAG WARNING IS WARRANTED.
WINDS WILL BE MARGINAL THIS AFTERNOOON BUT FUELS ARE DRY. 43

&&

.CLIMATE...
ISSUED A PNS WITH THE 2010 ANNUAL SUMMARY. OF INTEREST...COLLEGE
STATION HAD IT'S 7TH DRIEST DECEMBER AND ITS 11TH DRIEST YEAR. THE
WARMEST AUGUST ON RECORD WAS REPORTED BY ALL FOUR OF THE PRIMARY
CLIMATE SITES AND HOUSTON AND COLLEGE STATION RECORDED THEIR
WARMEST MONTH OF ALL TIME (AUGUST). 43

&&

.PREV DISCUSSION... /ISSUED 403 AM CST SAT JAN 1 2011/

MARINE...
THE COLD FRONT WAS PUSHING OFF THE COAST THIS MORNING AND EXPECT
SMALL CRAFT ADVISORY CONDITIONS TO DEVELOP OVER THE GULF WATERS
BEFORE 9 AM. THE LATEST MODEL GUIDANCE DIMINISHES THE WIND SPEEDS
A BIT FASTER THAN WAS EARLIER THOUGHT...AND THESE WILL LIKELY FALL
BELOW ADVISORY CONDITIONS WITHIN 20 NM BY THIS EVENING. HIGH
PRESSURE BUILDING ACROSS THE SOUTHERN PLAINS INTO THE LOWER
MISSISSIPPI VALLEY WILL THEN HELP TO SWING THE WINDS AROUND TO THE
NORTHEAST LATER TONIGHT AND SUNDAY. A COASTAL TROUGH IS POSSIBLE
BY TUESDAY AND WEDNESDAY.

40

PREV DISCUSSION... /ISSUED 233 AM CST SAT JAN 1 2011/

DISCUSSION...
CLOUDS CONTINUE TO HANG TOUGH THIS MORNING. WEAK ISENTROPIC
UPGLIDE SHOULD END THIS MORNING WITH DOWN GLIDE PREVAILING THIS
AFTERNOON. THIS SHOULD ALLOW FOR SKIES TO CLEAR AFTER 18Z. CLEAR
SKIES EXPECTED TONIGHT AND SUNDAY AS HIGH PRESSURE SETTLES OVER
SOUTHEAST TEXAS. THE HIGH SHIFTS EAST ON SUNDAY NIGHT AND MONDAY
WITH ONSHORE WINDS RETURNING. MOISTURE LEVELS SLOWLY INCREASE ON
MONDAY AND MONDAY NIGHT AS ONSHORE WINDS PERSIST. A WEAK COASTAL
TROUGH SHOULD DEVELOP TUESDAY MORNING AND THIS WILL FOCUS SOME
PRECIPITATION ALONG THE COAST TUES/TUES NIGHT. THE CAN AND ECMWF
ARE MORE AGGRESSIVE WITH RAIN CHANCES THAN THE GFS AND KEEP RAIN
GOING THROUGH WEDNESDAY. GENERALLY MOSTLY CLOUDY SKIES EXPECTED
THRU THURSDAY IN A RELATIVELY FAST FLOW ALOFT. MODELS DIVERGE
GREATLY BY FRIDAY AS THE ECMWF IS QUITE AGGRESSIVE WITH RAIN
CHANCES AS IT BRINGS A POTENT UPPER LEVEL SYSTEM ACROSS TEXAS. THE
CAN AND GFS ARE MUCH TAMER WITH WEAK RIDGING ALOFT. THE GFS
ADVERTISED THIS SYSTEM YESTERDAY BUT HAS NOW CHANGED ALMOST 180
DEGREES. WILL AGAIN BROAD BRUSH POPS AND SEE IF/WHEN MODELS
WILL BUILD A CONSENSUS. 43

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      61  34  57  35  60 /   0   0   0   0  10
HOUSTON (IAH)              63  38  59  37  61 /   0   0   0   0  10
GALVESTON (GLS)            63  45  57  46  60 /   0   0   0   0  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 3 PM CST THIS
     AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
     MATAGORDA BAY.

     SMALL CRAFT ADVISORY UNTIL 6 AM CST SUNDAY FOR THE FOLLOWING
     ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
     OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.

     SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 6 AM CST EARLY THIS
     MORNING FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
     THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
     ISLAND TO FREEPORT OUT 20 NM.

     SMALL CRAFT ADVISORY UNTIL 6 PM CST 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...43