Quantitative Precipitation Forecast
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FOUS30 KWBC 300752
QPFERD

EXCESSIVE RAINFALL DISCUSSION...CORRECTION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
350 AM EDT TUE AUG 30 2016

CORRECTION FOR CODING OF THE SLIGHT RISK IN SOUTHERN TX

...VALID 12Z TUE AUG 30 2016 - 12Z WED AUG 31 2016...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...


MARGINAL RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
80 WNW PIE 30 WSW CTY AYS 10 SW NBC 15 SE CPC OCW 10 WSW MQI
50 E MQI 80 E HSE.

MARGINAL RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
40 ESE PIL 15 SSE MMMA 25 SW MMRX 60 NE MMMY.

MARGINAL RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
95 SE DUG 60 SSW DMN 35 N SVC 50 W 4CR 25 SSE SKX 15 ENE VTP
25 SSE LXV 15 SSW BJC 20 NE MNH 25 ENE PUB 25 W SPD 50 ESE LAA
15 NNW MCK EAR 25 NNE OLU 20 NNW DNS 10 SW EST 15 SSW AUM
20 ENE DBQ 10 SE JVL AMN 15 SW PTK 20 WSW DFI 25 N ALN 10 SE PPF
30 WNW BVO 35 WSW CSM 10 SE SWW 30 W E29 25 N DRT 30 WSW UVA
30 E T82 CLL 25 WSW BPT 20 WSW KVBS.

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
25 NNE ALM 15 SE LVS 50 W CVS 15 E DHT 15 NNW PYX 10 S HHF
35 W LBB 40 S ODO 40 SE E38 45 S MRF 45 WNW MRF 40 E ELP
25 NNE ALM.

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
35 SSW HDE 25 SSE AUH 15 ESE CBF OXV 15 WSW SQI 10 E MDW
20 SSE IGQ 35 SE IRK 15 ENE LWC 15 NW HUT 35 WSW HYS 35 SSW HDE.

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
45 W SRQ 30 WNW PIE 15 S GNV 30 E SGJ.

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
25 E HST 30 E MTH 15 SE NQX 25 WSW KEY 55 WNW KEY.

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
10 NW KOPM 15 W KOPM 15 E BKS 20 NNW RBO VCT BYY 10 NE KBQX.

MODERATE RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
35 WSW FMY 25 NW PGD TTS 20 E COF.


DAY 1...

FLORIDA
~~~~~~~
THE TRACK OF T.D. #9 WILL CONTINUE INTO THE SOUTHEASTERN GULF OF
MEXICO BEFORE BECOMING A TROPICAL STORM DURING THE RECURVATURE
PROCESS TONIGHT AND WEDNESDAY MORNING. THIS WILL ALLOW FOR THE
CONTINUAL NORTHWARD PUSH OF 2-2.5" PRECIPITABLE WATER VALUES
ACROSS THE FL PENINSULA ON THE EAST TO NORTHEAST SIDE OF THE
CIRCULATION.  A CONVERGENCE BAND SETS UP OVER THE PENINSULA
BETWEEN THIS SYSTEM AND A NEW LOW OFFSHORE GA, ACTING AS A MORE
EFFECTIVE FOCUS FOR CONVECTION DURING DAYTIME HEATING (ROUGHLY
18Z-03Z).  GFS FORECASTS INDICATE 850 HPA INFLOW INCREASES TO
20-30 KTS WHILE SREF MEAN FIELDS INDICATE 2000 J/KG OF SURFACE
BASED CAPE.  WHEN COMBINED WITH EVACUATION ALOFT FROM AN UPPER LOW
TO THE NORTHEAST AND A POSSIBLE OUTFLOW JET FROM THE SLOWLY
DEVELOPING DEPRESSION, THE STAGE IS SET FOR WIDESPREAD MODERATE TO
HEAVY RAINS FOR CENTRAL TO SOUTH FLORIDA.  HIGH RESOLUTION
GUIDANCE IS VERY WET, SHOWING EITHER STRIPES OF 7"+ TOTALS, OR IN
THE CASE OF THE UNUSUALLY DRY NAM CONEST DUE TO ITS MORE WESTERLY
TRACK OF THE CYCLONE, LOCAL MAXIMA OF 5-7".  DUE TO THE STRONG
SIGNAL IN THE MESOSCALE GUIDANCE, AN UPGRADE TO A MODERATE RISK
WAS ADDED FOR PORTIONS OF THE PENINSULA SURROUNDING LAKE
OKEECHOBEE.  THIS WAS COORDINATED WITH THE MIAMI AND TAMPA FL
FORECAST OFFICES.


FAR EASTERN NC
~~~~~~~~~~~~~~
THE OFFICIAL FORECAST TRACK OF T.D. #8 WILL BRING THE CENTER JUST
OFFSHORE THE OUTER BANKS OF NC TUESDAY AFTERNOON.  AT THE MOMENT
WITH THIS SYSTEM RELATIVELY SMALL...THE EXPECTED AREA AFFECTED BY
ITS ASSOCIATED PRECIPITATION SHOULD REMAIN FAIRLY SMALL...CONFINED
TO FAR EASTERN NC INCLUDING THE OUTER BANKS. STORM TOTALS OF 1-3
INCHES AND SPOT AMOUNTS OF UP TO 5 INCHES ARE POSSIBLE.  KEPT THE
RISK OF EXCESSIVE RAINFALL MARGINAL DUE TO THE UNCERTAINTY
REGARDING HEAVY RAINS FROM A SYSTEM THAT CAN`T SEEM TO MAINTAIN
CENTRAL CONVECTION FOR VERY LONG.


SOUTHERN AND CENTRAL PLAINS AND MIDWEST
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
MODERATELY STRONG UPSLOPE FLOW COMBINED WITH A MOIST AIRMASS AND A
NEARBY BOUNDARY AT 850 HPA IS EXPECTED TO CAUSE ANOTHER BOUT OF
HEAVY RAINS ACROSS PORTIONS OF WESTERN TX AND SOUTHEAST NM.  A
SLIGHT RISK OF EXCESSIVE RAINFALL HAS BEEN ADDED, AS THE GUIDANCE
SHOWS LOCAL MAXIMA OF 2-4" OVER SATURATED SOILS IN THIS AREA.
FROM THE CENTRAL PLAINS EAST-NORTHEAST, WEAK LOW-LEVEL INFLOW
SHOULD KEEP CONVECTION OF A PULSE NATURE, THOUGH SIGNIFICANT
MOISTURE COULD MAKE THE CELLS EFFICIENT RAINFALL-WISE.  THE
MESOSCALE GUIDANCE HAS A CONSISTENT SIGNAL FOR LOCAL AMOUNTS IN
THE 3-5" RANGE.  ANOTHER SLIGHT RISK OF EXCESSIVE RAINFALL WAS
ADDED FROM NORTHERN KS/SOUTHEAST NE EASTWARD INTO THE NORTHERN
IL/FAR NORTHWEST IN WHERE SOILS ARE PARTIALLY SATURATED FROM
RECENT RAINS.


WESTERN GULF COAST
~~~~~~~~~~~~~~~~~~
THE MID TO UPPER LEVEL CIRCULATION INITIALLY ALONG THE UPPER TX
COAST IS EXPECTED TO MOVE SOUTHWEST, WHICH EVENTUALLY WEAKENS THE
LOW-LEVEL INFLOW INTO SOUTHERN TX BY WEDNESDAY MORNING. THE AXIS
OF ABOVE AVERAGE PW VALUES IN THE EASTERLY INFLOW MAX TO THE NORTH
OF THIS CENTER WILL CONTINUE TO SUPPORT HEAVY RAINFALL POTENTIAL
ALONG THE IMMEDIATE MID TO LOWER TX COAST, WITH A POSSIBLE SPREAD
INLAND OF PROGRESSIVE CONVECTIVE CELLS DURING DAYTIME HEATING
WHICH WILL THEN SET OFF OUTFLOW BOUNDARIES TO SET RAIN WEST AND
NORTHWEST.  MODEL CONSENSUS IS FOR SIGNIFICANT PRECIPITATION TO
NOT TO MAKE IT VERY FAR INLAND.  A SMALL SLIGHT RISK OF EXCESSIVE
RAINFALL WAS PLACED ACROSS PORTIONS OF THE MIDDLE AND LOWER TX
COAST, WITH ITS NORTHWARD EXTENT COORDINATED WITH THE
HOUSTON/GALVESTON TX FORECAST OFFICE.

ROTH
$$




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