MESOSCALE PRECIPITATION DISCUSSION 0094
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
422 AM EDT TUE APR 10 2018

AREAS AFFECTED...NORTHERN FL PENINSULA

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

VALID 100821Z - 101421Z

SUMMARY...ELEVATED CONVECTION IS SLOWLY DEVELOPING NEAR AND
UPSTREAM OF AN AREA WHICH RECEIVED HEAVY RAIN DURING THE PAST 12
HOURS.  HOURLY RAIN TOTALS TO 2" WITH LOCAL AMOUNTS TO 4" ARE
POSSIBLE.

DISCUSSION...A NARROW SHORTWAVE ALOFT ACROSS THE MOUTH OF THE
MISSISSIPPI RIVER AND SOUTHERN AL HAS LED TO RENEWED CONVECTION
OFFSHORE APALACHICOLA AND HALTED THE EROSION OF INSTABILITY ACROSS
NORTHERN FL.  FADED SURFACE BASED CONVECTION ACROSS THE CENTRAL FL
PENINSULA IS ALLOWING FOR NEW ELEVATED THUNDERSTORM DEVELOPMENT TO
THE NORTH ACROSS PORTIONS OF THE NORTHERN PENINSULA.  BROOKSVILLE
REPORTED 1.13" BETWEEN 07-08Z.  THE MOST RECENT GPS PRECIPITABLE
WATER VALUES LIE IN THE 1.6-1.75" RANGE.  A GRADIENT IN THE MU
CAPE FIELD EXISTS ACROSS THE NORTHERN PENINSULA WHERE 500-1000
J/KG CONTINUES TO EXIST PER SPC MESOANALYSES WHILE CENTRAL FL HAS
VALUES IN THE 1000-2000 J/KG RANGE. INFLOW AT 850 HPA IS
CONVERGENT OUT OF THE WEST SOUTHWEST AT 15-30 KT PER VAD WIND
PROFILES.  EFFECTIVE BULK SHEAR REMAINS IN THE 30-40 KNOT RANGE.

THE CONCERN IS THAT CONVECTION SOUTH OF THE FL PANHANDLE WOULD
BRIDGE ACROSS TO THE NORTHERN PENINSULA WHERE 2-6" OF RAIN FELL
SINCE 5 PM MONDAY AND LEAD TO RENEWED CELL TRAINING -- THERE IS
SOME SLIGHT EVIDENCE OF SHORT TRAINING BANDS DEVELOPING ASHORE AT
THIS TIME.  HRRR-BASED SOIL MOISTURE INDICATES SATURATED
CONDITIONS OVER MUCH OF THIS REGION, LEAVING IT SENSITIVE TO
ADDITIONAL RAINFALL.  THE 00Z NAM CONEST, SOUTHWARD ADJUSTED 06Z
NAM CONEST, 00Z CANADIAN REGIONAL, AND 00Z WRF NSSL RUNS APPEAR
BEST IN THIS AREA, AND ADVERTISE LOCAL AMOUNTS OF 3-4".  GIVEN THE
AMOUNT OF RESIDUAL INSTABILITY, HOURLY RAIN TOTALS TO 2" APPEAR
POSSIBLE.  UNCERTAINTY IS GREATER THAN AVERAGE IN THIS ASSESSMENT.

ROTH

ATTN...WFO...JAX...MLB...TAE...TBW...

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

LAT...LON   30198148 29998129 29528109 29058086 28488053
            28198133 28028214 28018285 28808280 29058287
            29118308 29448342 29708352 29778319 29938267