Apr 28, 2015 1300 UTC Day 1 Convective Outlook
Updated: Tue Apr 28 12:37:50 UTC 2015 (20150428 1300Z Day 1 shapefile | 20150428 1300Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20150428 1300 UTC Day 1 Outlook Graphic
Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
SLIGHT 26,061 10,406,367 Miami, FL...Tampa, FL...St. Petersburg, FL...Hialeah, FL...Fort Lauderdale, FL...
MARGINAL 48,978 8,808,142 New Orleans, LA...Orlando, FL...Mobile, AL...Tallahassee, FL...Metairie, LA...
Probabilistic Tornado Graphic
20150428 1300 UTC Day 1 Tornado Probabilities Graphic
Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Day 1 Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 20,142 8,747,177 Tampa, FL...St. Petersburg, FL...Fort Lauderdale, FL...Coral Springs, FL...Cape Coral, FL...
2 % 42,115 7,677,941 Miami, FL...Hialeah, FL...Orlando, FL...Mobile, AL...Pembroke Pines, FL...
Probabilistic Damaging Wind Graphic
20150428 1300 UTC Day 1 Damaging Wind Probabilities Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Day 1 Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
15 % 26,170 10,501,166 Miami, FL...Tampa, FL...St. Petersburg, FL...Hialeah, FL...Fort Lauderdale, FL...
5 % 49,322 8,706,716 New Orleans, LA...Orlando, FL...Mobile, AL...Tallahassee, FL...Metairie, LA...
Probabilistic Large Hail Graphic
20150428 1300 UTC Day 1 Large Hail Probabilities Graphic
Probability of hail 1" or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.
Day 1 Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
15 % 12,427 5,740,439 Fort Lauderdale, FL...Coral Springs, FL...Port St. Lucie, FL...West Palm Beach, FL...Sunrise, FL...
5 % 54,910 11,388,624 New Orleans, LA...Miami, FL...Tampa, FL...St. Petersburg, FL...Hialeah, FL...
   SPC AC 281237

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0737 AM CDT TUE APR 28 2015

   VALID 281300Z - 291200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS OVER SRN AND CNTRL FL...

   ...THERE IS A MRGL RISK OF SVR TSTMS OVER THE CNTRL AND ERN GULF CST
   REGION...

   ...SUMMARY...
   NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS THE CENTRAL
   AND EASTERN GULF COAST STATES TODAY AND TONIGHT. A FEW SEVERE STORMS
   ARE POSSIBLE...MAINLY OVER SOUTHERN AND CENTRAL FLORIDA.

   ...SYNOPTIC SETUP...
   BLOCKY...CONVOLUTED PATTERN WILL CONTINUE OVER NOAM THROUGH WED. IN
   THE SRN STREAM...N TX CLOSED LOW SHOULD MOVE ONLY SLOWLY E TO THE
   ARKLATEX THIS EVE. IT SHOULD ASSUME A SOMEWHAT GREATER EWD PACE TNGT
   AS IT DEVOLVES INTO A TROUGH OVER MS/AL UPON ENCOUNTERING CONFLUENT
   FLOW OVER THE E CNTRL U.S.  AT THE SFC...BROAD AREA OF WEAK LOW
   PRESSURE NOW COVERING THE CNTRL GULF OF MEXICO SHOULD BECOME A BIT
   MORE CONSOLIDATED WITH TIME...WITH THE MAIN CENTER REDEVELOPING NE
   TO THE FL CSTL BEND BY 12Z WED. OUTFLOW-REINFORCED FRONTAL ZONE NOW
   EXTENDING FROM SE LA ESE ACROSS S CNTRL FL SHOULD REMAIN QSTNRY
   TODAY...BEFORE EDGING NWD AS A WARM FRONT TNGT/EARLY WED. 

   ...CNTRL/ERN GULF CST STATES TODAY THROUGH EARLY WED...
   FAIRLY WIDESPREAD SHOWER/TSTM COVERAGE IS EXPECTED OVER THE CNTRL
   AND ERN GULF CST REGION THROUGH WED MORNING...NEAR AND AHEAD OF THE
   TX UPR SYS. WHILE SOME DIURNALLY-ENHANCED ACTIVITY LIKELY WILL OCCUR
   OVER LAND...THE MOST SIGNIFICANT STORMS SHOULD FOCUS NEAR
   AFOREMENTIONED SFC FRONT AND ASSOCIATED OUTFLOW BOUNDARIES...THAT
   IS...OVER THE GULF WATERS. TWO OVERLAND AREAS THAT MIGHT SEE STRONG
   TO POSSIBLY SVR STORMS TODAY INCLUDE THE SRN HALF OF THE FL
   PENINSULA...AND CSTL PORTIONS OF SE LA...MS...AND AL. 

   STORM POTENTIAL OVER THE FL PENINSULA WILL BE TIED TO THE CONTINUED
   E/SE REDEVELOPMENT OF GULF MCS NOW CENTERED ABOUT 150 MILES W OF
   TPA. RICH MOISTURE /PW TO 2.00 INCHES/ AND FILTERED SFC HEATING
   COULD SOMEWHAT OFFSET MODEST MID-LVL LAPSE RATES TO PROMOTE NEW
   STORM DEVELOPMENT ALONG STNRY FRONT AND SEA BREEZE BOUNDARIES.
   MID-LVL WIND FIELD WILL REMAIN FAIRLY MODEST /700 MB WLY FLOW AROUND
   25-30 KTS/...BUT SUFFICIENT FOR ORGANIZED STORMS/POSSIBLE
   SUPERCELLS...ESPECIALLY ALONG SFC BOUNDARIES. THESE COULD PRODUCE
   LOCALLY DMGG WINDS...HAIL...AND PERHAPS A TORNADO OR TWO /FOR
   NEAR-TERM INFO REF MCD 485/.

   OVER SE LA AND CSTL MS-AL...STORMS MAY FORM ALONG INVERTED SFC
   TROUGH EXTENDING N FROM THE CNTRL GULF OF MEXICO...WHERE MID-LVL
   TEMPS WILL SOMEWHAT COOL WITH THE APPROACH OF THE TX UPR SYSTEM. THE
   STORMS COULD YIELD MARGINALLY SVR HAIL...DESPITE THE FACT THAT THE
   STRONGEST ACTIVITY SHOULD REMAIN OFFSHORE NEAR SFC FRONT.  

   A SECOND ROUND OF STRONG TO POSSIBLY SVR STORMS MAY APPROACH CNTRL
   AND SRN PORTIONS THE FL W CST EARLY WED AS WIND FIELD AND FORCING
   FOR ASCENT INCREASE OVER THE ERN GULF IN ASSOCIATION WITH
   APPROACHING UPR TROUGH. THE PRIMARY RISK WHERE ANY SUSTAINED STORMS
   ARE ABLE TO MOVE INLAND FROM THE GULF WOULD BE LOCALLY DMGG WIND.
   CONFIDENCE IN THIS SCENARIO ATTM IS...HOWEVER...NOT HIGH GIVEN
   EXPECTED MODEST DEGREE OF BUOYANCY.

   ..CORFIDI/COOK/COHEN.. 04/28/2015

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z