Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS01 KWNS 041933
SWODY1
SPC AC 041932

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0232 PM CDT WED MAY 04 2016

VALID 042000Z - 051200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE EXTREME SOUTHERN FL
PENINSULA AND THE FL KEYS...

...THERE IS A MRGL RISK OF SVR TSTMS ACROSS FAR SOUTHERN FL...

...SUMMARY...
A FEW DAMAGING GUSTS AND MARGINALLY SEVERE HAIL WILL BE POSSIBLE
THIS AFTERNOON ACROSS EXTREME SOUTH FLORIDA AND THE FLORIDA KEYS.

...EXTREME S FL INTO THE KEYS...

CONVECTION MOVING ACROSS THE SOUTHERN PENINSULA THIS AFTERNOON HAS
LARGELY OVERTURNED THE AIRMASS WITH TEMPS IN THE 60S AND LOW 70S
WITH INCREASING CIN NOTED IN OBJECTIVE ANALYSIS. BETTER AIRMASS WITH
INSTABILITY NEAR 1000-1500 J/KG MLCAPE RESIDES OVER THE EXTREME
SOUTHERN PENINSULA THROUGH THE KEYS. RADAR SHOWS A BOWING SEGMENT
TRACKING EAST/NORTHEAST TOWARD THE KEYS...WHICH SHOULD ARRIVE IN THE
NEXT COUPLE OF HOURS. THIS COULD STILL PRODUCE SOME STRONG WIND
GUSTS AND MAYBE HAIL. FURTHER NORTH...THE SEVERE THREAT HAS LARGELY
DIMINISHED. AS SUCH...THE RISK AREA HAS BEEN CONFINED TO THE FAR
SOUTHERN PENINSULA AND THE KEYS WHERE AIRMASS REMAINS RELATIVELY
UNAFFECTED BY EARLIER STORMS.

..LEITMAN.. 05/04/2016

.PREV DISCUSSION... /ISSUED 1129 AM CDT WED MAY 04 2016/

...S FL THIS AFTERNOON...
PRE-FRONTAL BAND OF CONVECTION IS ONGOING OVER CENTRAL/S FL...WHILE
THE SYNOPTIC COLD FRONT IS LOCATED FROM THE NC COAST TO N FL.  THE
COLD POOL ASSOCIATED WITH THE CONVECTION SHOULD DRIFT SWD ACROSS S
FL THROUGH THE AFTERNOON AND FOCUS ADDITIONAL THUNDERSTORM
DEVELOPMENT...AS A SERIES OF EMBEDDED SHORTWAVE TROUGH ROTATE EWD
AROUND THE SRN PERIPHERY OF AN AMPLIFYING TROUGH OVER THE OH VALLEY.
 SURFACE TEMPERATURES HAVE WARMED INTO THE LOWER 80S WITH DEWPOINTS
IN THE LOWER 70S ACROSS S FL...AND THIS IS CONTRIBUTING TO RECENT
THUNDERSTORM DEVELOPMENT IN SE FL.  HOWEVER...ADDITIONAL SURFACE
HEATING WILL BE SLOWED BY ANVIL CLOUDINESS OVERSPREADING S FL FROM
THE ERN GULF STORMS...AND LOCAL VWP/S SHOW SUFFICIENT VERTICAL SHEAR
IN THE LOW-MID LEVELS FOR SOME ORGANIZED/PERSISTENT STORMS.
THUS...THE MAIN SEVERE THREAT SHOULD BE A FEW DAMAGING GUSTS AND
MARGINALLY SEVERE HAIL WITH MULTICELL CLUSTERS/LINE SEGMENTS AS THE
ERN GULF CONVECTION SPREADS INLAND...OR NEW STORMS FORM ALONG THE
OUTFLOW BOUNDARY.

...OH/TN VALLEYS THIS AFTERNOON...
COLD MIDLEVEL TEMPERATURES AND RELATIVELY STEEP LAPSE RATES
ACCOMPANY THE DIGGING MIDLEVEL TROUGH OVER THE LOWER OH VALLEY.
LOW-TOPPED CONVECTION IS EXPECTED IN A BAND IN ADVANCE OF BELT OF
STRONG FORCING FOR ASCENT ACROSS KY/TN.  MARGINAL LOW-LEVEL MOISTURE
WILL LIMIT THE MAGNITUDE OF BUOYANCY...SUCH THAT STORMS ARE EXPECTED
TO REMAIN SUB-SEVERE WITH GUSTY WINDS AND SMALL HAIL.

...NC COAST THIS AFTERNOON...
THE SURFACE COLD FRONT IS MOVING SLOWLY SEWD NEAR THE NC COAST.  A
FEW THUNDERSTORMS COULD DEVELOP ALONG THE BOUNDARY THIS AFTERNOON
ALONG THE COAST AS AN EMBEDDED SHORTWAVE TROUGH ROTATES ENEWD OVER
NC/VA.  THERE IS A NON-ZERO THREAT FOR A STRONG STORM WITH GUSTY
WINDS AND/OR SOME HAIL...BUT THE OVERALL RISK APPEARS TOO MARGINAL
TO ADD ANY PROBABILITIES IN THIS UPDATE.

$$



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