Alert archive / Georgia / Mesoscale Discussions in 2012

Mesoscale Discussion 2228

December 26, 20124 counties in Florida; 20 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Dec 26, 2012, 2:55 AM CST for 4 counties in Florida; 20 counties in Georgia. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued
Dec 26, 2012, 2:55 AM CST (08:55 UTC)
Expired
Dec 26, 2012, 4:00 AM CST
In force
65 min
Issued by
the Storm Prediction Center
All 24 counties

Calhoun County, FL, Gadsden County, FL, Gulf County, FL, Liberty County, FL, Baker County, GA, Bibb County, GA, Calhoun County, GA, Crawford County, GA, Decatur County, GA, Dougherty County, GA, Early County, GA, Lee County, GA, Macon County, GA, Marion County, GA, Miller County, GA, Peach County, GA, Randolph County, GA, Schley County, GA, Seminole County, GA, Sumter County, GA, Taylor County, GA, Terrell County, GA, Upson County, GA, Webster County, GA

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 00:00Z, 8.9 hours before the alert went out and 141 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 00:00Z on 2012-12-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2012-12-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 232 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1109 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
232 m²/s²
0-3 km storm-relative helicity
410 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.

543 
ACUS11 KWNS 260856
SWOMCD
SPC MCD 260855
GAZ000-FLZ000-ALZ000-261000-

MESOSCALE DISCUSSION 2228
NWS STORM PREDICTION CENTER NORMAN OK
0255 AM CST WED DEC 26 2012

AREAS AFFECTED...PORTIONS OF SWRN GA AND CENTRAL FL PANHANDLE

CONCERNING...TORNADO WATCH 698...

VALID 260855Z - 261000Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 698 CONTINUES.

SUMMARY...TSTMS WILL LIKELY CLEAR REMAINING PORTIONS OF WW 698 BY
09Z. A LOCAL WFO EXTENSION MAY BE NEEDED ACROSS FL PANHANDLE PORTION
OF WW HOWEVER OVERALL TRENDS SUGGEST A NEW WW WILL NOT BE NEEDED.

DISCUSSION...LINE OF TSTMS CONTINUES TO MOVE EWD AND WILL EXIT
REMAINING VALID PORTIONS OF WW 698 BY AROUND 09Z. LATEST
MESOANALYSIS DATA INDICATES A NARROW AXIS OF MUCAPE OF 500-1000 J/KG
EXISTS ACROSS CENTRAL FL PANHANDLE AND INTO EXTREME SWRN GA. IN
ADDITION...0-1 KM SRH VALUES OF 350 M2/S2 OR HIGHER IN THIS REGION
SUGGESTS AT LEAST SOME POTENTIAL FOR LOW-LEVEL ROTATION FOR AN
ADDITIONAL 1 TO 2 HOURS. IN ADDITION...RADAR DATA FROM KTLH HAS
DETECTED BRIEF CIRCULATIONS WITHIN CONVECTIVE LINE. THUS...A LOCAL
WFO EXTENSION OF WW 698 TO THE EAST OF THE CURRENT AREA MAY BE
NEEDED.

ELSEWHERE...TSTMS WILL BE MOVING EAST OF THE INSTABILITY AXIS AFTER
09Z AND INTO A LESS FAVORABLE ENVIRONMENT. THUS..A NEW WW IS NOT
ANTICIPATED ATTM.

..BUNTING/MEAD.. 12/26/2012

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

ATTN...WFO...FFC...TAE...

LAT...LON   32988432 32988357 29678485 29688555 32988432

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 25, 8:49 PM CSTMesoscale DiscussionSPCBay, Calhoun, Escambia, Gulf, Holmes, Jackson and 5 more56 min
Dec 25, 9:23 PM CSTTornado WatchSPCBay, Calhoun, Escambia, Franklin, Gadsden, Gulf and 9 more6 hr
Dec 25, 11:10 PM CSTMesoscale DiscussionSPCBay, Calhoun, Gadsden, Gulf, Holmes, Jackson and 3 more95 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.