Alert archive / Florida / Mesoscale Discussions in 2016

Mesoscale Discussion 281

March 29, 201616 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Mar 29, 2016, 1:17 PM EDT for 16 counties in Florida. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Mar 29, 2016, 1:17 PM EDT (17:17 UTC)
Expired
Mar 29, 2016, 3:45 PM EDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Broward County, FL, Charlotte County, FL, Collier County, FL, DeSoto County, FL, Glades County, FL, Hardee County, FL, Hendry County, FL, Highlands County, FL, Lee County, FL, Manatee County, FL, Martin County, FL, Miami-Dade County, FL, Monroe County, FL, Okeechobee County, FL, Palm Beach County, FL, Sarasota County, FL

The radar

The Tampa radar (KTBW), 131 km from the middle of the area, began a volume at 17:17 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, 5.3 hours before the alert went out and 130 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 2016-03-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1606 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 2016-03-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 10 square meters per square second.193958Sfc1 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
1606 J/kg
Mixed-layer CIN
-26 J/kg
Mixed-layer LCL
866 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
10 m²/s²
0-3 km storm-relative helicity
53 m²/s²
Significant tornado parameter
0.3
Supercell composite
1.4

Open this sounding in Storm Lab

The text

As transmitted.

457 
ACUS11 KWNS 291717
SWOMCD
SPC MCD 291717 
FLZ000-291945-

MESOSCALE DISCUSSION 0281
NWS STORM PREDICTION CENTER NORMAN OK
1217 PM CDT TUE MAR 29 2016

AREAS AFFECTED...CENTRAL/SOUTHERN FL

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 291717Z - 291945Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...ISOLATED SEVERE HAIL/WIND ARE POSSIBLE THIS AFTERNOON
ACROSS THE SOUTHERN HALF OF THE FL PENINSULA.

DISCUSSION...A MID-LEVEL SHORTWAVE TROUGH OVER THE EASTERN GULF OF
MEXICO PER WATER VAPOR IMAGERY WILL CONTINUE A STEADY EASTWARD
PROGRESSION TOWARD THE CENTRAL/SOUTHERN FL PENINSULA THIS
AFTERNOON...WITH A PRECEDING WELL-ORGANIZED LINEAR CLUSTER EXPECTED
TO CONTINUE TO APPROACH THE WESTERN/SOUTHERN PENINSULA. INCREASING
FORCING FOR ASCENT WITH THE AFOREMENTIONED SHORTWAVE
TROUGH...DIFFERENTIAL HEATING/SEA BREEZE CIRCULATIONS...ALONG WITH
CLUSTER-RELATED-COLD POOL UPLIFT AS IT NEARS THE COAST...WILL
SUPPORT MULTIPLE CORRIDORS OF INCREASINGLY STRONG THUNDERSTORMS
THROUGH THE AFTERNOON ACROSS THE SOUTHERN HALF OF THE FL PENINSULA.
ALTHOUGH LOW-LEVEL WINDS WILL REMAIN WEAK...RELATIVELY STEEP
MID-LEVEL LAPSE RATES AND MODERATE BUOYANCY...AS SAMPLED BY 12Z
OBSERVED SOUNDINGS...IN THE PRESENCE OF INCREASINGLY STRONG
/SUPERCELL-ADEQUATE/ SHEAR WILL SUPPORT THE POTENTIAL FOR ISOLATED
INSTANCES OF SEVERE HAIL/WIND THROUGH AFTERNOON AND EARLY EVENING.

..GUYER/THOMPSON.. 03/29/2016

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

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

LAT...LON   27618297 27698156 27298027 25228022 25328115 26528229
            27618297

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.