Alert archive / Florida / Mesoscale Discussions in 2012

Mesoscale Discussion 1271

June 25, 201231 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Jun 25, 2012, 12:06 PM EDT for 31 counties in Florida. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued
Jun 25, 2012, 12:06 PM EDT (16:06 UTC)
Expired
Jun 25, 2012, 1:00 PM EDT
In force
54 min
Issued by
the Storm Prediction Center
All 31 counties

Alachua County, FL, Bradford County, FL, Brevard County, FL, Citrus County, FL, Clay County, FL, Dixie County, FL, Gilchrist County, FL, Hardee County, FL, Hernando County, FL, Highlands County, FL, Hillsborough County, FL, Indian River County, FL, Lafayette County, FL, Lake County, FL, Levy County, FL, Manatee County, FL, Marion County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Pinellas County, FL, Polk County, FL, Putnam County, FL, Saint Lucie County, FL, Sarasota County, FL, Seminole County, FL, Sumter County, FL, Taylor County, FL, Union County, FL, Volusia County, FL

The radar

The Tampa radar (KTBW), 137 km from the middle of the area, began a volume at 16:07 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 4.1 hours before the alert went out and 137 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 2012-06-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1113 joules per kilogram.LCLEL10008507005003002001001 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 2012-06-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 116 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
1113 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
509 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
116 m²/s²
0-3 km storm-relative helicity
158 m²/s²
Significant tornado parameter
0.4
Supercell composite
3.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

827 
ACUS11 KWNS 251606
SWOMCD
SPC MCD 251606 
FLZ000-251700-

MESOSCALE DISCUSSION 1271
NWS STORM PREDICTION CENTER NORMAN OK
1106 AM CDT MON JUN 25 2012

AREAS AFFECTED...FL

CONCERNING...TORNADO WATCH 424...

VALID 251606Z - 251700Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 424 CONTINUES.

SUMMARY...ISOLATED TORNADOES REMAIN POSSIBLE ACROSS THE FL
PENINSULA.

DISCUSSION...TROPICAL STORM DEBBY HAS MOVED LITTLE OVER THE LAST FEW
HOURS AND LIGHTNING-PRODUCING CONVECTION REMAINS SPARSE. 
HOWEVER...SERN-MOST CONFLUENT BAND HAS RECENTLY INTENSIFIED ACROSS
THE SRN FL PENINSULA FROM COLLIER COUNTY TO LAKE OKEECHOBEE WHERE
LIGHTNING HAS BEEN OBSERVED.  WEAK ROTATION HAS ALSO BEEN NOTED WITH
DEEPER SHOWERS AND ISOLATED THUNDERSTORMS FROM OKEECHOBEE COUNTY NWD
INTO OSCEOLA COUNTY.  ADDITIONALLY...ANOTHER DEEP BAND OF CONVECTION
WILL APPROACH THE SWRN FL PENINSULA NEAR FMY IN THE NEXT FEW HOURS. 
GIVEN THESE TRENDS THE GREATEST THREAT FOR ISOLATED TORNADOES OVER
THE NEXT FEW HOURS APPEARS TO HAVE SHIFTED TO THE SRN HALF OF THE
WW.

..DARROW.. 06/25/2012

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

ATTN...WFO...MLB...TBW...JAX...TAE...

LAT...LON   30058451 30068167 27207994 27208270 30058451

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 24, 10:16 PM EDTMesoscale DiscussionSPCBrevard, Charlotte, Citrus, Collier, DeSoto, Dixie and 20 more59 min
Jun 25, 12:46 AM EDTMesoscale DiscussionSPCAlachua, Charlotte, Citrus, DeSoto, Dixie, Gilchrist and 14 more89 min
Jun 25, 4:07 AM EDTMesoscale DiscussionSPCBradford, Charlotte, Clay, Collier, DeSoto, Duval and 21 more83 min
Jun 25, 4:37 AM EDTTornado WatchSPCAlachua, Brevard, Charlotte, Citrus, Collier, DeSoto and 35 more9 hr
Jun 25, 1:48 PM EDTTornado WatchSPCAlachua, Baker, Bradford, Brevard, Charlotte, Citrus and 45 more9 hr
Jun 25, 6:27 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Brevard, Charlotte, Citrus and 45 more63 min

Nearby

Mesoscale Discussions in Florida, 2012Every mesoscale discussion in 2012

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.