MESOSCALE PRECIPITATION DISCUSSION 0097
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
116 PM EDT TUE MAR 29 2016
 
AREAS AFFECTED...CENTRAL AND SOUTHERN FLORIDA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 291714Z - 292214Z
 
SUMMARY...HEAVY SHOWERS AND THUNDERSTORMS WITH RAINFALL RATES OF 1
TO 3 INCHES PER HOUR ARE EXPECTED TO CAUSE SOME RUNOFF PROBLEMS
AND POSSIBLE FLASH FLOODING IN SOME URBAN AREAS.

DISCUSSION...CURRENT SATELLITE IMAGERY SHOWS WIDESPREAD COLD
CONVECTIVE TOPS WITH AN MCS OVER THE NORTHEASTERN GULF OF MEXICO
IN ASSOCIATION WITH A COMPACT SUBTROPICAL SHORTWAVE.  THIS
DISTURBANCE IS STEADILY TRACKING TOWARDS THE EAST AND IS EXPECTED
TO CROSS THE FLORIDA PENINSULA THROUGH THE MID TO LATE AFTERNOON
HOURS.  

THE LATEST SURFACE ANALYSIS INDICATES A QUASI-STATIONARY FRONT
DRAPED ACROSS THE CENTRAL PART OF THE STATE, WITH DEWPOINTS IN THE
LOWER 70S SOUTH OF THE BOUNDARY.  DOPPLER RADAR IMAGERY OVER THE
OFFSHORE WATERS IS INDICATING NUMEROUS SLOW MOVING THUNDERSTORM
CELLS WITHIN A LARGER AREA OF STRATIFORM PRECIPITATION.  TRAINING
CONVECTION IS MOST LIKELY AHEAD OF THE VORTMAX.  GIVEN RECENT
RADAR AND SATELLITE TRENDS OVER THE PAST FEW HOURS, IT APPEARS
LIKELY THAT THIS ACTIVITY SHOULD HOLD TOGETHER BY THE TIME IT
CROSSES THE PENINSULA.

SOUTH OF THE FRONT, PW VALUES ARE IN THE 1.5 TO 2 INCH RANGE OVER
SOUTH FLORIDA, AND NEAR 1.25 INCHES OVER CENTRAL FLORIDA. IN
ADDITION, MLCAPE VALUES ON THE ORDER OF 1500 TO 2500 J/KG AS
DEPICTED BY THE LATEST SPC MESOSCALE ANALYSIS WILL HELP SUPPORT
AREAS OF VIGOROUS CONVECTION.

OVER THE NEXT FEW HOURS, RECENT RUNS OF THE HRRR, ARW, AND NMMB
SUGGEST PATCHY AREAS OF 3+ INCH RAINFALL TOTALS THROUGH 22Z,
MAINLY SOUTH OF THE ORLANDO AREA.  IN THOSE AREAS THAT GET
TRAINING CONVECTIVE ACTIVITY, RAINFALL RATES ARE EXPECTED TO BE
VERY HIGH GIVEN THE ELEVATED PWS AND INSTABILITY.  CONVERGENCE
ALONG SEA BREEZE BOUNDARIES WILL ALSO HELP GENERATE AREAS OF HEAVY
RAINFALL.  ONE OF THE MITIGATING FACTORS THAT WILL REDUCE THE
AMOUNT OF FLOODING THAT OCCURS ARE THE RELATIVELY HIGH FLASH FLOOD
GUIDANCE VALUES.  THE MAIN CONCERN WILL BE EXCESSIVE SHORT-TERM
RUNOFF PROBLEMS AND POSSIBLE FLASH FLOODING OF MAINLY URBAN AREAS.

HAMRICK

ATTN...WFO...KEY...MFL...MLB...TBW...

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

LAT...LON   28668115 28598032 28058013 27067992 26107989 
            25338008 24858042 24508123 24418189 24558230 
            24848223 25288200 25918210 26538248 27048286 
            27618313 28018313 28428304 28628263 28638185