Alert archive / Florida / Mesoscale Discussions in 2012

Mesoscale Discussion 231

March 3, 201221 counties in Florida; 9 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Mar 3, 2012, 12:45 PM EST for 21 counties in Florida; 9 counties in Georgia. It was in force for 60 min.

The area

The outline as issued.

The facts

Issued
Mar 3, 2012, 12:45 PM EST (17:45 UTC)
Expired
Mar 3, 2012, 1:45 PM EST
In force
60 min
Issued by
the Storm Prediction Center
All 30 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Clay County, FL, Columbia County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Hamilton County, FL, Jefferson County, FL, Lafayette County, FL, Leon County, FL, Liberty County, FL, Madison County, FL, Nassau County, FL, Putnam County, FL, Saint Johns County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL, Wakulla County, FL, Brantley County, GA, Brooks County, GA, Camden County, GA, Charlton County, GA, Clinch County, GA, Echols County, GA, Lanier County, GA, Lowndes County, GA, Ware County, GA

The watches that followed

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

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 5.8 hours before the alert went out and 116 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, Tallahassee Rgnl, FL at 12:00Z on 2012-03-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 499 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, Tallahassee Rgnl, FL at 12:00Z on 2012-03-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 257 square meters per square second.1939587897Sfc1 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
499 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
472 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
257 m²/s²
0-3 km storm-relative helicity
283 m²/s²
Significant tornado parameter
0.9
Supercell composite
4.1

Open this sounding in Storm Lab

The text

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

635 
ACUS11 KWNS 031746
SWOMCD
SPC MCD 031745
FLZ000-GAZ000-031845-

MESOSCALE DISCUSSION 0231
NWS STORM PREDICTION CENTER NORMAN OK
1145 AM CST SAT MAR 03 2012

AREAS AFFECTED...NRN FL...SE GA

CONCERNING...TORNADO WATCH 68...

VALID 031745Z - 031845Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 68 CONTINUES.

A NEW WW REPLACING WW 68 LIKELY WILL BE ISSUED SOON.

WITH A SIGNIFICANT SHORT WAVE IMPULSE STILL DIGGING UPSTREAM...
TOWARD THE WESTERN/CENTRAL GULF COAST REGION...THE COMPOSITE
NORTHEAST-SOUTHWEST ORIENTED SURFACE FRONT/OUTFLOW BOUNDARY IS
EXPECTED TO ONLY SLOWLY ADVANCE SOUTHWARD THROUGH NORTHERN FLORIDA
THIS AFTERNOON.  THE BULK OF THE VIGOROUS CONVECTIVE DEVELOPMENT
LIKELY WILL REMAIN ALONG AND TO THE IMMEDIATE NORTH OF THIS
BOUNDARY...WHERE PERSISTENT/TRAINING ACTIVITY COULD YIELD LOCALLY
EXCESSIVE RAIN TOTALS.  HOWEVER...INHIBITION IS GRADUALLY WEAKENING
TO THE IMMEDIATE SOUTH OF THE FRONT...DUE TO CONTINUED SURFACE
HEATING AND WEAK COOLING ALOFT.  COUPLED WITH LIFT ASSOCIATED WITH
WARM ADVECTION...DISCRETE STORM DEVELOPMENT APPEARS IMMINENT AROUND
THE JACKSONVILLE AREA.  DEEP LAYER AND LOW-LEVEL SHEAR REMAINS
FAVORABLE FOR SUPERCELLS CAPABLE OF PRODUCING AN ISOLATED TORNADO OR
TWO...ALONG WITH LOCALLY DAMAGING WIND GUSTS...PERHAPS SOME HAIL.

..KERR.. 03/03/2012

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

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

LAT...LON   30348527 30698411 31058329 31398192 31248156 30648145
            29428118 29138164 29278221 29458252 29978349 29648457
            29938522 30348527

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 2, 11:56 PM ESTTornado WatchSPCEscambia6 hr
Mar 3, 5:47 AM ESTMesoscale DiscussionSPCBay, Calhoun, Escambia, Franklin, Gadsden, Gulf and 10 more58 min
Mar 3, 7:35 AM ESTTornado WatchSPCBay, Calhoun, Franklin, Gadsden, Gulf, Hamilton and 9 more6 hr
Mar 3, 10:12 AM ESTMesoscale DiscussionSPCBay, Calhoun, Gadsden, Hamilton, Jefferson, Leon and 3 more93 min
Mar 3, 1:04 PM ESTTornado WatchSPCAlachua, Baker, Bradford, Calhoun, Clay, Columbia and 17 more5 hr
Mar 3, 4:30 PM ESTMesoscale DiscussionSPCBaker, Columbia, Hamilton, Lafayette, Nassau, Suwannee and 2 more90 min
Mar 2, 8:15 PM ESTMesoscale DiscussionSPCCatoosa, Dade, Fannin, Gilmer, Murray, Rabun and 4 more90 min
Mar 2, 8:18 PM ESTMesoscale DiscussionSPCDade57 min
Mar 2, 9:36 PM ESTMesoscale DiscussionSPCBaker, Calhoun, Colquitt, Cook, Decatur, Dougherty and 6 more54 min
Mar 2, 10:54 PM ESTTornado WatchSPCBanks, Barrow, Bartow, Butts, Carroll, Catoosa and 61 more6 hr
Mar 2, 11:07 PM ESTMesoscale DiscussionSPCCarroll, Clayton, Cobb, Coweta, DeKalb, Douglas and 13 more113 min
Mar 3, 12:40 AM ESTMesoscale DiscussionSPCBanks, Barrow, Bartow, Carroll, Cherokee, Clarke and 30 more95 min
Mar 3, 3:58 AM ESTMesoscale DiscussionSPCBurke, Columbia, Glascock, Jefferson, Jenkins, Lincoln and 6 more92 min
Mar 3, 4:39 AM ESTSevere Thunderstorm WatchSPCBurke, Columbia, Lincoln, McDuffie, Richmond4 hr

Nearby

Mesoscale Discussions in Florida, 2012Mesoscale Discussions in Georgia, 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.