AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
454 PM CDT SAT AUG 26 2017
...CATASTROPHIC AND LIFE-THREATENING FLOODING EXPECTED DUE TO
PROLONGED HEAVY RAINFALL FROM HARVEY...
DISCUSSION
WITH HARVEY MEANDERING JUST WEST OF THE FORECAST AREA, RAIN AND
FEEDER BANDS WILL MOVE OVER SOUTHEAST TEXAS UNTIL THE STORM MOVES
OUT OF THE AREA. SHORT TERM HIGH RESOLUTION MODELS SHOW THE
POTENTIAL FOR RAIN BANDS TO PRODUCE 10 TO 15 INCHES OF RAIN JUST
TONIGHT AND SUNDAY MORNING. RAINFALL OF 10 TO 15 INCHES WITHIN 6
OR 12 HOURS WILL PRODUCE FLASH FLOODING. IN ADDITION, RAINFALL
RATES COULD EXCEED 4 INCHES PER HOUR. IF THESE INTENSE RAIN BANDS
WITH THESE AMOUNTS OCCUR OVER THE METRO AREAS, FLOODING COULD
IMPACT HOMES, ROADWAYS, AND THE HIGHWAY SYSTEM.
IN ADDITION, ISOLATED TORNADOES WILL CONTINUE TO BE POSSIBLE. A
TORNADO WATCH CONTINUES IN EFFECT THROUGH 2:00 AM SUNDAY.
WITH HARVEY PRETTY MUCH STUCK IN VERY WEAK UPPER LEVEL STEERING,
THE POTENTIAL FOR HEAVY RAINFALL WILL PERSIST INTO WEDNESDAY.
GLOBAL MODELS CONTINUE TO SHOW THE RAINFALL POTENTIAL FROM TONIGHT
THROUGH WEDNESDAY EVENING OF 15 TO 25 INCHES. ISOLATED MAXIMUM
AMOUNTS OF UP TO 40 INCHES FOR THE ENTIRE EVENT IS POSSIBLE.
IT SHOULD BE STRESSED THAT ANYONE PLANNING TO TRAVEL SHOULD CHECK
WITH TXDOT, HOUSTON TRANSTAR, OR OTHER TRUSTED SOURCES FOR ROAD
CONDITIONS PRIOR TO TRAVEL. RAINFALL OF THIS MAGNITUDE COULD CAUSE
MAJOR FLOODING OF THE HIGHWAY SYSTEM.