000
FXUS64 KHGX 181704
AFDHGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1204 PM CDT SAT MAY 18 2013

.DISCUSSION...
SEE 18Z AVIATION DISCUSSION.

&&

.AVIATION...
OTHER THAN REDUCED VISIBILITY AT TIMES FROM SMOKE...GENERALLY VFR
CONDS EXPECTED THROUGH 05Z. MOISTURE BENEATH THE CAP WILL ALLOW
MVFR CIGS TO DEVELOP AGAIN. LEANED TOWARD PERSISTENCE ONCE AGAIN
WITH MVFR CIGS OVERNIGHT AND MXING OUT BETWEEN 15-16Z. GRADIENT
LOOKS TIGHTER ON SUNDAY SO WILL ADD A GUST GROUP. 43

&&

.PREV DISCUSSION... /ISSUED 1023 AM CDT SAT MAY 18 2013/

DISCUSSION...
A HIGH PRESSURE RIDGE WAS PRESENT ACROSS SE TX THIS MORNING. THE
SURFACE PRESSURE GRADIENT WAS FAIRLY TIGHT...ESPECIALLY OVER THE
WESTERN COUNTIES AND COASTAL MARINE ZONES. AN ANALYSIS OF THE 12Z
UPPER AIR PRESSURE SURFACES SHOWED A VERY WARM LAYER OVERHEAD.
THIS WAS CONFIRMED BY THE LARGE CAP IN PLACE ON THE 12Z SOUNDINGS
AT KCRP...KLCH...AND KSHV. A FAIRLY DEEP LOW-LEVEL SOUTHERN FLOW
FROM THE SURFACE TO ABOVE 850MB WAS HELPING TO ADVECT SMOKE FROM
SOUTHEASTERN MEXICO OVERHEAD OUR AREA. FURTHER ALOFT THE MID AND
HIGH LEVEL RIDGE WAS MOVING OVERHEAD THE EASTERN PART OF THE
STATE.

WITH ALL THIS IN MIND...EXPECT A HAZY AFTERNOON TO DEVELOP AS THE
MORNING CLOUDINESS SCATTERS OUT. THE SMOKE AND HAZE SHOULD HELP
GENERATE A BIT OF A GREENHOUSE EFFECT AND WARM TEMPERATURES UP A
BIT OVER THE INLAND SITES. TOWARD THE COAST...THE ONSHORE FLOW OFF
THE COOLER GULF WATERS WILL HELP MODERATE TEMPERATURES. UPDATES
WERE TO THE WIND GRIDS AND ADDED AN SCEC TO THE MARINE GROUPS
BEYOND 20 NM AND WEST OF FREEPORT WITHIN 20 NM AND INCLUDING
MATAGORDA BAY.

40

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      91  72  91  73  91 /  10  10  10  10  10
HOUSTON (IAH)              90  72  90  73  91 /  10  10  10  10  10
GALVESTON (GLS)            82  73  82  73  82 /  10  10  10  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 6 PM CDT THIS EVENING
     FOR THE FOLLOWING ZONES: MATAGORDA BAY...WATERS FROM
     FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...
     WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20
     NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM.

&&

$$

DISCUSSION...40
AVIATION/MARINE...43