Quantitative Precipitation Forecast
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FOUS30 KWBC 310121
QPFERD

EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
920 PM EDT SAT AUG 30 2014

...VALID 03Z SUN AUG 31 2014 - 00Z MON SEP 01 2014...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...


SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
15 NW SME 35 E MQY 30 NW MDQ 15 W MSL 30 NNE TUP 40 ESE OLV
30 ESE NQA 35 SSE PAH HNB 40 NNE LOU 25 ENE LEX 15 NW SME.

MADE SOME CHANGES TO THE PREVIOUS ISSUANCE..MAINLY TO REMOVE
SOUTHWESTERN PORTIONS OF THE AREA.  THE AXIS OF MUCH ABOVE AVERAGE
PW VALUES WILL CONTINUE TO BE DRAWN NORTHEASTWARD THIS PERIOD IN
THE SOUTHWESTERLY MID TO UPPER LEVEL FLOW AHEAD OF THE ELONGATED
MEAN TROF PUSHING EASTWARD FROM THE MS VALLEY.  THE WELL DEFINED
SOUTHERN STREAM AREA OF HEIGHT FALLS COMPRISING THE SOUTHERN
PORTION OF THE ELONGATED TROF WILL BE THE PRIMARY FOCUSING
MECHANISM FOR HEAVY RAINFALL AMOUNTS IN THE ABOVE AVERAGE PW PLUME
AS WELL DEFINED UPPER DIFFLUENCE ENHANCES UVVS AHEAD OF THESE
HEIGHT FALLS AS THEY PUSH NORTHEASTWARD.   TRAINING OF CELLS IN A
GENERAL SOUTH SOUTHWESTERLY TO NORTH NORTHEASTERLY DIRECTION IS
LIKELY AHEAD OF THESE HEIGHT FALLS.  IN AREAS OF TRAINING--1-2"+
RAINFALL AMOUNTS IN AN HOUR OR TWO AND ISOLATED TOTALS OF 3-5"+
POSSIBLE.


...TEXAS GULF COAST...

WHILE SIGNIFICANT HEIGHT FALLS ALONG THE WESTERN TO CENTRAL GULF
COAST ARE EXPECTED TO LIFT NORTHEASTWARD THIS PERIOD--A SEPARATE
MID TO UPPER LEVEL CIRCULATION WILL REMAIN NEARLY STATIONARY OFF
THE LOWER TX COAST THROUGH SATURDAY NIGHT---FORECAST TO DRIFT
WESTWARD AND INLAND DURING THE DAY ON SUNDAY.  LOCALLY VERY HEAVY
RAINS HAVE DEVELOPED IN THE VICINITY OF THIS CIRCULATION OVER THE
PAST FEW DAYS--AFFECTING THE IMMEDIATE COASTAL SECTIONS OF THE
LOWER TO MID TX GULF COAST.  EXPECT THIS POTENTIAL TO CONTINUE
THIS PERIOD---WITH THE BEST CHANCE OF CONVECTIVE ENHANCEMENT IN
THE EARLY MORNING HOURS OF SUNDAY.  VERY HEAVY TO ISOLATED
EXCESSIVE RAINFALL AMOUNTS POSSIBLE ALONG THE LOWER TO MID TX
COASTAL AREAS WITH ISOLATED SHORT TERM PRECIPITATION TOTALS OF
1-3" IN AN HOUR OR TWO.  WHILE FFG VALUES ARE HIGH---RUNOFF
PROBLEMS STILL POSSIBLE FROM INTENSE RAINFALL RATES--ESPECIALLY
OVER MORE URBANIZED REGIONS.

TERRY


$$




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.