Flash Flood Warning 20, NWS Houston/Galveston, TX

SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
220 AM CDT WED SEP 13 2000

CONVECTION OCCURRING TONIGHT ALONG COASTAL SECTIONS OF SE TX WHERE
OUTFLOW BOUNDARY HAS COLLIDED WITH NORTHERN PORTION OF TROPICAL WAVE.
MODELS INDICATE THAT THIS WILL CONTINUE TONIGHT AND LIKELY BE
ONGOING FOR START OF 1ST PD.

MAIN ISSUES FOR THIS PACKAGE ARE CHC OF RAIN AND FRONT AT THE END OF
THE PD. FAVOR THE AVN MODEL PRECIP FIELD. WILL TAPER SLIGHTLY FROM S
TO N TODAY TO ACCOUNT FOR OUTFLOW BOUNDARY AND POSITION OF DEEP
TROPICAL MOISTURE (> 2 INCHES). SLIGHTLY LESS MOISTURE AVAILABLE FOR
NORTHERN SECTIONS OF FA. WITH REGION ON EAST SIDE OF UPPER LEVEL
SHEAR AXIS...DECENT DIVERGENCE ALOFT WILL CONTINUE OVER SE TX THRU
TODAY...WHICH SUPPORTS CONTINUED GOOD CHC OF RAIN. LOCALLY HEAVY
RAIN A GOOD BET...HOWEVER HARD TO PINPOINT WHO WILL GET IT DUE TO
THE MESO-SCALE INTERACTIONS. EASTERN EDGE OF MID-LEVEL RIDGE WILL
PROVIDE FOR MORE SUBSIDENCE ON THU SO WILL ONLY INCLUDE SLIGHT CHC
ON THU AND FRI.

AS PATN AMPLIFICATION OCCURS TOWARDS END OF THE PD...CF WILL PUSH
INTO SE TX ON FRIDAY AND LIKELY BRING COOLER TEMPS TO THE REGION
THIS WEEKEND. SE TX WILL LIE BETWEEN IMPRESSIVE RIDGE PARKED OVER
THE FOUR CORNERS AREA AND DEEP LOW JUST NORTH OF THE OHIO VALLEY.
AVN GUID INDICATING SIGNIFICANT COOLING FOR FRI HIGH TEMPS. BELIEVE
COOLING IS OVER-DONE DUE TO MID-LEVEL RIDGE AND DRIER AIRMASS IN
PLACE...SO WILL WAIT FOR SAT BEFORE LOWERING HIGH TEMPS.

THE TROPICAL WAVE IN THE CARIBBEAN HAS THE POTENTIAL FOR DEVELOPMENT
THIS WEEK AS IT TRACKS TO THE NW INTO THE GULF. CF EXPECTED TO BE IN
GULF BY LATE FRI WHICH WOULD HELP STEER ANY TROPICAL SYSTEM SOUTH OF
THE UPPER TX COAST. THEREFORE...FORECAST WILL NOT INCLUDE RAIN CHCS
FOR THE WEEKEND.

33/47

.KHGX...NONE

CLL TB 091/070 094/069 092 532
IAH TB 090/071 093/069 091 632
GLuS TB 088/079 088/077 089 632

TXZ163-164-176>179-195>200-210>214-226-227-235>238-132100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
530 AM CDT WED SEP 13 2000

...LOCALLY HEAVY RAINFALL TODAY ACROSS SOUTHEAST TEXAS...

THE COMBINATION OF DEEP MOISTURE ASSOCIATED WITH A TROPICAL WAVE
PUSHING INLAND OFF OF THE GULF AND AN UPPER AIR DISTURBANCE OVER THE
AREA IS EXPECTED TO PRODUCE SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS ACROSS SOUTHEAST TEXAS TODAY.

NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG COASTAL AND
SOUTHERN PORTIONS OF SOUTHEAST TEXAS WITH SCATTERED THUNDERSTORMS
EXPECTED ACROSS NORTHERN PORTIONS OF THE AREA. DUE TO ABUNDANT
MOISTURE IN PLACE...LOCALLY HEAVY RAINFALL IS EXPECTED TODAY. AVERAGE
RAINFALL AMOUNTS ARE EXPECTED TO BE AROUND TO 1 TO 2 INCHES WITH
ISOLATED AMOUNTS IN EXCESS OF 4 INCHES.

THE SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED TO DECREASE DURING
THE EVENING HOURS WITH THE LOSS OF DAYTIME HEATING AND DUE TO THE
TROPICAL WAVE MOVING FURTHER INLAND.

MOTORISTS SHOULD BE ON THE ALERT TODAY FOR PONDING OF WATER
AND LOCALIZED STREET FLOODING. REMEMBER...DO NOT CROSS AREAS WHERE
WATER COVERS THE ROADWAY.

STAY TUNED TO NOAA WEATHER RADIO OR OTHER NEWS SOURCES FOR THE
LATEST WEATHER INFORMATION. YOU CAN ALSO FIND MORE INFORMATION
ON OUR WEBSITE WWW.SRH.NOAA.GOV/HGX