Graphic for MPD #0746

MESOSCALE PRECIPITATION DISCUSSION 0746
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
826 PM EDT SUN AUG 27 2017

AREAS AFFECTED...WEST CENTRAL AND SOUTHWEST FL

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 280030Z - 280630Z

SUMMARY...SLOW MOVING CONVECTION IN A HIGH MOISTURE ENVIRONMENT
COULD RESULT IN A FLASH FLOOD THREAT INTO EARLY MORNING ACROSS
PORTIONS OF WEST CENTRAL AND SOUTHWEST FL.

DISCUSSION...BANDS OF CONVECTION MOVING EASTWARD FROM THE GULF OF
MEXICO CONTINUE TO TRAIN NEAR THE COAST OF WEST CENTRAL AND
SOUTHWEST FL EARLY THIS EVENING. THE CONVECTION IS FORMING IN AN
AREA OF 1000-100 J/KG OF MLCAPE LOCATED OVER THE EASTERN GULF OF
MEXICO AND MUCH OF SOUTHWEST FL.

THE AIRMASS IN WHICH THE CONVECTION IS FORMING AND MOVING HAS
PRECIPITABLE WATER VALUES NEAR 2.50 INCHES...AND THE 00Z TBW 
SOUNDING SHOWED A MOIST COLUMN UP THROUGH 500 MB...WITH FREEZING
LEVELS ABOVE 16000 FEET. WARM RAIN PROCESSES ARE DOMINATING THE
CONVECTION...THOUGH THE GOES-16 CLEAN IR LOOP SHOWED STEADILY
COOLING TOPS WEST OF KPGD.

THE CONVECTION IS EXPECTED TO CONTINUE COMING ASHORE ALONG THE
WEST COAST OF FL BETWEEN KSRQ AND KFMY THROUGH THE EARLY MORNING
HOURS. HOURLY RAINFALL RATES COULD BRIEFLY JUMP TO NEAR 2.00
INCHES DURING THE MID TO LATE EVENING HOURS...AND THE MOST RECENT
HRRR SHOWED LOCAL 3.00 TO 5.00 INCHES OF RAINFALL ALONG THIS
CORRIDOR.

HEAVY RAINFALL OCCURRED OVER PORTIONS OF WEST CENTRAL AND
SOUTHWEST FL SATURDAY NIGHT INTO THIS AFTERNOON...WITH THE HIGHEST
AMOUNTS IN THE FORT MYERS/CAPE CORAL AREA. THE ADDITIONAL HEAVY
RAINFALL COULD RESULT IN FLASH FLOODING...ESPECIALLY IN URBAN
CENTERS AND AREAS OF POOR DRAINAGE. FLASH FLOODING IS ONLY
CONSIDERED POSSIBLE...SINCE IT IS UNCLEAR JUST HOW MUCH OF THE
CONVECTION MAKES IT WAY ONSHORE.

HAYES

ATTN...WFO...MFL...TBW...

ATTN...RFC...SERFC...

LAT...LON   28348288 28308243 27468202 26838179 26388168
            26108174 26108190 26498221 28028290


Last Updated: 826 PM EDT SUN AUG 27 2017