Alert archive / Florida / Mesoscale Discussions in 2016

Mesoscale Discussion 381

April 14, 2016Osceola County, Polk County, Florida

The Storm Prediction Center issued this mesoscale discussion at Apr 14, 2016, 7:06 PM EDT for Osceola County, Polk County, Florida. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued
Apr 14, 2016, 7:06 PM EDT (23:06 UTC)
Expired
Apr 14, 2016, 8:30 PM EDT
In force
84 min
Issued by
the Storm Prediction Center
Chance of a watch
5%

Counties Osceola County, FL, Polk County, FL

The radar

The Melbourne radar (KMLB), 77 km from the middle of the area, began a volume at 23:07 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 11.1 hours before the alert went out and 101 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Tampa Bay, FL at 12:00Z on 2016-04-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 112 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tampa Bay, FL at 12:00Z on 2016-04-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
112 J/kg
Mixed-layer CIN
-201 J/kg
Mixed-layer LCL
804 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

768 
ACUS11 KWNS 142306
SWOMCD
SPC MCD 142306 
FLZ000-150030-

MESOSCALE DISCUSSION 0381
NWS STORM PREDICTION CENTER NORMAN OK
0606 PM CDT THU APR 14 2016

AREAS AFFECTED...CNTRL FLORIDA PENINSULA

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 142306Z - 150030Z

PROBABILITY OF WATCH ISSUANCE...5 PERCENT

SUMMARY...STRONG/SEVERE STORM DEVELOPMENT MAY CONTINUE ANOTHER
COUPLE OF HOURS...BUT IS EXPECTED TO REMAIN RELATIVELY ISOLATED OVER
THE INTERIOR CENTRAL PENINSULA.

DISCUSSION...A COUPLE OF STORMS WHICH INITIATED OFF THE WEST COAST
SEA BREEZE HAVE ADVECTED INTO THE INTERIOR CENTRAL PENINSULA. 
WITHIN THE NEXT HOUR OR SO...IT APPEARS THAT THEY MAY MERGE...AND
INTERACT WITH THE INLAND ADVANCING...OUTFLOW-ENHANCED EAST COAST SEA
BREEZE.  AS THIS OCCURS...IN THE PRESENCE OF CAPE IN EXCESS OF 1000
J/KG...AND AT LEAST MODEST DEEP LAYER SHEAR BENEATH 30-35 KT
MID-LEVEL FLOW...THERE APPEARS POTENTIAL FOR FURTHER INTENSIFICATION
THROUGH 00-01Z.  

ALREADY THIS AFTERNOON...MRMS DATA SUGGEST THAT STRONGEST STORMS
HAVE BEEN OCCASIONALLY PRODUCING SEVERE HAIL.  THIS LIKELY REMAINS
POSSIBLE...WITH PERHAPS SOME INCREASING RISK FOR A STRONG DOWNBURST
WITH ANY UPSCALE CONVECTIVE GROWTH.  MUCH OF THIS THREAT MAY REMAIN
CONCENTRATED OVER RELATIVELY UNPOPULATED AREAS OF POLK AND OSCEOLA
COUNTIES...TO THE SOUTHWEST AND SOUTH OF KISSIMMEE AND ST.
CLOUD...BEFORE DIMINISHING THIS EVENING.

..KERR/EDWARDS.. 04/14/2016

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...MLB...TBW...

LAT...LON   27938184 28358171 28388137 28118114 27708083 27428100
            27418133 27628145 27938184

Nearby

Mesoscale Discussions in Florida, 2016Every mesoscale discussion in 2016

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.