Alert archive / Georgia / Mesoscale Discussions in 2012

Mesoscale Discussion 343

March 24, 201214 counties in Florida; 31 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Mar 24, 2012, 10:16 AM EDT for 14 counties in Florida; 31 counties in Georgia. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued
Mar 24, 2012, 10:16 AM EDT (14:16 UTC)
Expired
Mar 24, 2012, 11:15 AM EDT
In force
59 min
Issued by
the Storm Prediction Center
All 45 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Clay County, FL, Columbia County, FL, Duval County, FL, Gilchrist County, FL, Hamilton County, FL, Lafayette County, FL, Madison County, FL, Nassau County, FL, Putnam County, FL, Suwannee County, FL, Union County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Berrien County, GA, Brantley County, GA, Bryan County, GA, Bulloch County, GA, Camden County, GA, Candler County, GA, Charlton County, GA, Chatham County, GA, Clinch County, GA, Coffee County, GA, Echols County, GA, Effingham County, GA, Evans County, GA, Glynn County, GA, Jeff Davis County, GA, Lanier County, GA, Liberty County, GA, Long County, GA, Lowndes County, GA, McIntosh County, GA, Montgomery County, GA, Pierce County, GA, Tattnall County, GA, Telfair County, GA, Toombs County, GA, Ware County, GA, Wayne County, GA, Wheeler 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

Jacksonville, FL (KJAX), launched 12:00Z, 2.3 hours before the alert went out and 80 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, Jacksonville, FL at 12:00Z on 2012-03-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 139 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, Jacksonville, FL at 12:00Z on 2012-03-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
139 J/kg
Mixed-layer CIN
-87 J/kg
Mixed-layer LCL
982 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
121 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

400 
ACUS11 KWNS 241417
SWOMCD
SPC MCD 241416
SCZ000-GAZ000-FLZ000-241515-

MESOSCALE DISCUSSION 0343
NWS STORM PREDICTION CENTER NORMAN OK
0916 AM CDT SAT MAR 24 2012

AREAS AFFECTED...NRN FL...SERN GA

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 241416Z - 241515Z

SEMI-DISCRETE TSTMS ACROSS THE ERN FL PANHANDLE INTO S-CNTRL GA
SHOULD INTENSIFY AND POSE A RISK FOR ISOLATED SEVERE STORMS AS
ACTIVITY MOVES EWD TOWARDS THE ATLANTIC COAST. THE PROBABILITY OF A
WW ISSUANCE IS 80 PERCENT AND SLIGHT RISK WILL BE EXPANDED SWD IN
THE 1630Z D1 OUTLOOK.

TSTMS DEVELOPING WITHIN A PRE-FRONTAL CONFLUENCE BAND COINCIDENT
WITH THE AXIS OF STRONGER INSTABILITY...CHARACTERIZED BY MLCAPE NEAR
1500 J/KG AS SAMPLED BY THE 12Z TLH RAOB...SHOULD INTENSIFY AS
DIURNAL DESTABILIZATION INCREASES. THIS SCENARIO IS SUPPORTED BY
CONVECTION-ALLOWING MODEL GUIDANCE WITH SEVERAL TSTM CLUSTERS LIKELY
DEVELOPING EWD INTO THIS AFTERNOON. VWP DATA FROM KVAX DEPICTS
VEERING OF THE LOWER-LEVEL WIND PROFILE THAT IS SUPPORTING 0-1 KM
SRH OF 100-150 M2/S2. WITH EFFECTIVE DEEP-LAYER SHEAR OF 30-40
KT...EMBEDDED SUPERCELL STRUCTURES APPEAR PROBABLE...POTENTIALLY
YIELDING ISOLATED DAMAGING WINDS...MARGINALLY SEVERE HAIL AND A
BRIEF TORNADO.

..GRAMS.. 03/24/2012

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

ATTN...WFO...CHS...TBW...JAX...FFC...TAE...

LAT...LON   31388327 32028298 32488230 32528151 32398114 32208093
            30738154 29928140 29458161 29338240 29408282 29678343
            30148363 30808351 31388327

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 24, 10:45 AM EDTSevere Thunderstorm WatchSPCAlachua, Baker, Bradford, Clay, Columbia, Duval and 7 more8 hr
Mar 24, 12:29 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Duval and 4 more61 min
Mar 24, 4:19 PM EDTMesoscale DiscussionSPCBaker, Bradford, Clay, Columbia, Duval, Hamilton and 4 more86 min
Mar 24, 6:25 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Citrus, Clay, Columbia and 11 more65 min
Mar 24, 4:16 PM EDTMesoscale DiscussionSPCRichmond59 min
Mar 24, 5:52 PM EDTMesoscale DiscussionSPCChattooga, Dade, Walker53 min

Nearby

Mesoscale Discussions in Georgia, 2012Mesoscale 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.