Quantitative Precipitation Forecast
Issued by NWS

Current Version | Previous Version | Graphics & Text | 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 280122
QPFERD

EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
922 PM EDT MON JUL 27 2015

...VALID 01Z TUE JUL 28 2015 - 12Z TUE JUL 28 2015...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...


SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
35 S CWVP 45 SW CWWF 15 NNE CWPO 15 SE KGAF 25 W FFM 15 ENE MKT
20 SE MCW 20 NE CIN 25 SE YKN 30 ESE ICR 10 NW IEN 40 NNE RCA
15 NNE 2WX 35 WSW BHK 55 SSW MLS 35 NNE GEY 55 ESE LWT
45 ENE LWT 40 ENE GFA 35 S CWVP.

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
MLI PRG 15 E HNB 25 ENE CKV 30 SSE CIR 40 E VIH 10 W MPZ MLI.


01Z UPDATE...


OVER WESTERN FL...WEAKENING DEEP-LAYER INSTABILITY ALONG WITH THE
WEAK OVERALL LOW LEVEL INFLOW EARLY THIS EVENING IS LEADING TO
LESS INTENSE RAINFALL RATES ACROSS WEST-CENTRAL FL.
HOWEVER...TRAINING OF CONVECTION PERSISTING ALONG THE PERIPHERY OF
THE NEARLY STATIONARY SURFACE LOW NEAR TAMPA...WITH THE CONTINUED
MOISTURE FLUX CONVERGENCE AND HIGH PWS (2.25-2.5
INCHES)...CONTINUE TO EXPECT HIGHLY EFFICIENT WARM RAIN PROCESSES
AND POTENTIALLY EXCESSIVE SHORT TERM RAINFALL RATES OVER ISOLATED
AREAS.


...SOUTHWEST TO WEST CENTRAL FLORIDA...

A SLIGHT RISK AREA WAS CONTINUED ALONG COASTAL SECTIONS OF
SOUTHWEST TO WEST CENTRAL FLORIDA.  NO SIGNIFICANT CHANGES
EXPECTED TO THE ELONGATED VORT AXIS STRETCHING FROM THE EASTERN
GULF OF MEXICO ACROSS FLORIDA.  A WEAK LOW LEVEL H85 CENTER OFF
THE SOUTHWEST TO WEST COAST OF FLORIDA---HOWEVER--- IS FORECAST TO
DRIFT SLOWLY NORTHWARD THIS PERIOD.  MOIST ONSHORE WEST SOUTHWEST
FLOW TO THE SOUTH OF THIS WEAK CENTER WILL AGAIN FOCUS HEAVY
RAINFALL POTENTIAL ACROSS SOUTHWEST TO WEST CENTRAL PORTIONS OF
FLORIDA.  SIMILAR TO THE PREVIOUS DAYS---ISOLATED VERY HEAVY
RAINFALL TOTALS OF 5"+ POSSIBLE---CONTINUING THE POTENTIAL FOR
ISOLATED RUNOFF ISSUES--ESPECIALLY IN URBANIZED AREAS.


...NORTHERN PLAINS SOUTHEAST TOWARD THE MID MISSISSIPPI VALLEY...

MODELS ARE IN GOOD AGREEMENT WITH THE AMPLIFICATION OF THE UPPER
TROF MOVING FROM THE NORTHERN GREAT BASIN--ACROSS THE NORTHERN
ROCKIES AND INTO THE NORTHERN PLAINS MONDAY INTO EARLY TUESDAY.
WIDESPREAD HEAVY PRECIPITATION TOTALS POSSIBLE IN A DEVELOPING
COMMA HEAD DEFORMATION PRECIPITATION AREA IN A REGION OF
STRENGTHENING UPPER DIFFLUENCE AND ABOVE AVERAGE PW VALUES FROM
PORTIONS OF THE NORTHERN ROCKIES INTO THE NORTHERN HIGH PLAINS.
THERE IS A STRONG MODEL SIGNAL FOR HEAVY PRECIPITATION TOTALS IN
THIS COMMA HEAD--WITH ISOLATED RUNOFF ISSUES POSSIBLE ACROSS
NORTHEASTERN PORTIONS OF MT.

FARTHER TO THE EAST---FRONTAL/PRE-FRONTAL CONVECTION LIKELY TO
ENHANCE MONDAY AFTERNOON INTO MONDAY NIGHT ACROSS PORTIONS OF THE
NORTHERN PLAINS IN A REGION OF VERY STRONG FRONTAL CONVERGENCE.  A
WELL DEFINED CONVECTIVE LINE POSSIBLE TO PUSH EASTWARD MONDAY
NIGHT INTO EARLY TUE THROUGH THE NORTHERN PLAINS AND TOWARD THE
UPPER MS VALLEY.  THIS WILL ALSO SUPPORT ISOLATED RUNOFF ISSUES
SPREADING EASTWARD INTO NORTHERN TO EASTERN ND AND INTO WESTERN
MN.  THIS CONVECTIVE LINE---HOWEVER--- MAY BECOME VERY PROGRESSIVE
MONDAY NIGHT/EARLY TUESDAY---A POSSIBLE LIMITING FACTOR FOR VERY
HEAVY RAIN TOTALS OVER EASTERN PORTIONS OF THE NORTHERN PLAINS
INTO THE UPPER MS VALLEY.  AT THE MOMENT---BEST CHANCES FOR RUNOFF
ISSUES WITH THIS CONVECTIVE LINE MAY BE LATE AFTERNOON INTO EARLY
EVENING BEFORE THE INCREASED CHANCES OF EASTWARD ACCELERATION.


ORAVEC/SULLIVAN/HURLEY
$$




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