Alert archive / Georgia / Mesoscale Discussions in 2004

Mesoscale Discussion 2174

September 6, 200427 counties in Florida; 45 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Sep 6, 2004, 4:06 AM EDT for 27 counties in Florida; 45 counties in Georgia. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued
Sep 6, 2004, 4:06 AM EDT (08:06 UTC)
Expired
Sep 6, 2004, 5:30 AM EDT
In force
84 min
Issued by
the Storm Prediction Center
All 72 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Clay County, FL, Columbia County, FL, Dixie County, FL, Duval County, FL, Flagler County, FL, Franklin County, FL, Gadsden County, FL, Gilchrist County, FL, Hamilton County, FL, Jefferson County, FL, Lafayette County, FL, Leon County, FL, Levy County, FL, Liberty County, FL, Madison County, FL, Marion County, FL, Nassau County, FL, Putnam County, FL, Saint Johns County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL, Volusia County, FL, Wakulla County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Baker County, GA, Ben Hill County, GA, Berrien County, GA, Brantley County, GA, Brooks County, GA, Bryan County, GA, Calhoun County, GA, Camden County, GA, Charlton County, GA, Clay County, GA, Clinch County, GA, Coffee County, GA, Colquitt County, GA, Cook County, GA, Decatur County, GA, Dougherty County, GA, Early County, GA, Echols County, GA, Glynn County, GA, Grady County, GA, Irwin County, GA, Jeff Davis County, GA, Lanier County, GA, Lee County, GA, Liberty County, GA, Long County, GA, Lowndes County, GA, McIntosh County, GA, Miller County, GA, Mitchell County, GA, Pierce County, GA, Quitman County, GA, Randolph County, GA, Seminole County, GA, Tattnall County, GA, Terrell County, GA, Thomas County, GA, Tift County, GA, Turner County, GA, Ware County, GA, Wayne County, GA, Worth 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 00:00Z, 8.1 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, Jacksonville, FL at 00:00Z on 2004-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 498 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, Jacksonville, FL at 00:00Z on 2004-09-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 95 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
498 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
529 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
95 m²/s²
0-3 km storm-relative helicity
110 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.5

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 060809
SWOMCD
SPC MCD 060806 
FLZ000-GAZ000-ALZ000-060930-

MESOSCALE DISCUSSION 2174
NWS STORM PREDICTION CENTER NORMAN OK
0306 AM CDT MON SEP 06 2004

AREAS AFFECTED...SRN GA/NRN FL

CONCERNING...TORNADO WATCH 802...

VALID 060806Z - 060930Z

GREATEST TORNADO POTENTIAL THROUGH 10 OR 11Z IS EXPECTED TO PERSIST
OVER SERN GA...WITH A SLOW EWD SHIFT ACROSS S-CNTRL GA/N-CNTRL FL
LATER THIS MORNING. A REPLACEMENT WW WILL LIKELY BE ISSUED WITHIN
THE NEXT 1-1.5 HOURS.

LATEST CHS REFLECTIVITY/VELOCITY DATA SHOW A RAINBAND WITH SEVERAL
EMBEDDED MESOCYCLONES FROM 60S CHS WWD TO 30W OF SAV WITH A GENERAL
STORM MOTION OF 115/35. SYNTHESIS OF RUC OBJECTIVE FIELDS WITH
CURRENT VWP DATA SUGGEST THAT CORRIDOR FROM THE MOUTH OF THE
SAVANNAH RIVER SWD TO THE FL BORDER AND INLAND 80-100NM REMAINS MOST
FAVORABLE FOR ISOLATED TORNADOES WITH MLCAPES OF 500 J/KG AND 0-1KM
SRH VALUES OF 300-350 M2/S2.

EXPECT HIGHEST PROBABILITY OF TORNADOES TO PERSIST ACROSS THIS SAME
GENERAL AREA FOR THE NEXT SEVERAL HOURS OWING TO THE SLOW MOVEMENT
OF PARENT TROPICAL SYSTEM. THREAT AREA SHOULD TEND TO SHIFT SLOWLY
WWD INTO S-CNTRL GA/N-CNTRL FL LATER THIS MORNING.

..MEAD.. 09/06/2004

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

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

32008515 31798287 32138221 32098128 31498081 28848082
29368513

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 5, 8:35 PM EDTTornado WatchSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 21 more9 hr
Sep 6, 12:12 AM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 21 more2 hr
Sep 6, 4:50 AM EDTTornado WatchSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 11 more9 hr
Sep 6, 7:48 AM EDTMesoscale DiscussionSPCBrevard, Charlotte, DeSoto, Hardee, Highlands, Lake and 8 more87 min
Sep 6, 7:55 AM EDTTornado WatchSPCBrevard, Charlotte, Citrus, DeSoto, Glades, Hardee and 21 more6 hr
Sep 6, 12:28 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Brevard, Charlotte, Citrus and 36 more92 min
Sep 6, 1:20 PM EDTTornado WatchSPCAlachua, Baker, Bradford, Brevard, Citrus, Clay and 38 more7 hr
Sep 6, 3:55 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Duval and 10 more2 hr
Sep 6, 7:12 PM EDTMesoscale DiscussionSPCBaker, Columbia, Duval, Nassau, Union2 hr
Sep 6, 7:45 PM EDTTornado WatchSPCBradford, Clay, Duval, Flagler, Nassau, Putnam and 1 more9 hr
Sep 6, 1:21 AM EDTMesoscale DiscussionSPCRichmond84 min
Sep 6, 1:00 PM EDTTornado WatchSPCAppling, Atkinson, Bacon, Ben Hill, Berrien, Bleckley and 49 more7 hr

Nearby

Mesoscale Discussions in Georgia, 2004Mesoscale Discussions in Florida, 2004Every mesoscale discussion in 2004

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.