MESOSCALE PRECIPITATION DISCUSSION 0305
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1026 AM EDT TUE JUN 06 2017
AREAS AFFECTED...PORTIONS OF WESTERN & CENTRAL FL
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE
VALID 061425Z - 062025Z
SUMMARY...SHOWERS AND THUNDERSTORMS ARE EXPECTED TO EXPAND IN
COVERAGE DUE TO DAYTIME HEATING NEAR MERGING WARM FRONTS LIFTING
NORTHEAST ACROSS THE FL PENINSULA. HOURLY RAIN RATES UP TO 3" WITH
LOCAL AMOUNTS UP TO 6" ARE EXPECTED.
DISCUSSION...A NEW BATCH OF SHOWERS AND THUNDERSTORMS HAS RECENTLY
DEVELOPED OVER WESTERN SECTIONS OF COLLIER COUNTY AS A WEAK WARM
FRONT ACROSS THE GULF OF MEXICO MARCHES NORTHEAST. INFLOW AT 850
HPA IS SLIGHTLY CONVERGENT OUT OF THE SOUTHWEST AT 25-30 KTS PER
VAD WIND PROFILES. EFFECTIVE BULK SHEAR OF ~25 KTS EXISTS IN THIS
REGION, WHICH COULD HELP ORGANIZE CONVECTION MORE THAN THE USUAL
PULSE ACTIVITY SEEN ACROSS THE FL PENINSULA IN THE RAINY SEASON.
PRECIPITABLE WATER VALUES ARE AT OR ABOVE 2.25". MLCAPES ARE
500-1500 J/KG AND RISING WHILE CIN IS REDUCING WITHIN THE AREA OF
SUNNY SKIES.
RAP FORECASTS SHOW THE WEAK GULF WARM FRONT PHASING IN WITH
ANOTHER WEAK WARM FRONT IN THE WESTERN PENINSULA WITH TIME. NOW
THAT THE SUN IS OUT, SEA BREEZE CIRCULATIONS SHOULD AID THE
EFFICIENCY OF ANY CONVECTIVE ACTIVITY NEAR THE WEAK THERMAL/DEW
POINT BOUNDARY. MLCAPES SHOULD RISE ANOTHER 1000 J/KG ACROSS
WEST-CENTRAL AND CENTRAL FL INTO THIS AFTERNOON. HOURLY RAIN
RATES UP TO 3" ARE POSSIBLE WHERE CELLS MERGE OR TRAIN WITHIN THE
CONFLUENT LOW-LEVEL FLOW REGIME. LOCAL MAXIMA UP TO 6" ARE
POSSIBLE, THOUGH SUCH MAXIMA SHOULD BE SPOTTY. MOST OF THE
GUIDANCE THUS FAR HAS BEEN TOO FAR NORTH AND NORTHWEST WITH THE
CONVECTION OVER NORTHERN FL. THE 00Z ARW, 06Z NAM CONEST, AND TO
SOME DEGREE THE 06Z CANADIAN REGIONAL GUIDANCE APPEAR TO HAVE THE
BEST HANDLE ON THE PRECIPITATION PATTERN EXPECTED IN THIS AREA IN
THE NEXT SEVERAL HOURS. URBAN AREAS SHOULD SEE THE MOST
SIGNIFICANT IMPACT. FOR RURAL AREAS/THE ORANGE GROVES OF CENTRAL
FL, THE RAINFALL WOULD BE BENEFICIAL AS THE REGION HAS BEEN IN A
SIGNIFICANT DRY SEASON-INDUCED DROUGHT.
ROTH
ATTN...WFO...JAX...MFL...MLB...TBW...
ATTN...RFC...SERFC...
LAT...LON 29198128 28368109 27858116 27148124 25878136
25878164 26058197 26828251 27308281 27828280
28938207
Last Updated: 1026 AM EDT TUE JUN 06 2017