Alert archive / Georgia / Mesoscale Discussions in 2011

Mesoscale Discussion 2245

October 10, 201111 counties in Florida; 16 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Oct 10, 2011, 8:30 AM EDT for 11 counties in Florida; 16 counties in Georgia. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Oct 10, 2011, 8:30 AM EDT (12:30 UTC)
Expired: Oct 10, 2011, 10:00 AM EDT
In force: 90 min
Issued by: the Storm Prediction Center

All 27 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Clay County, FL, Columbia County, FL, Duval County, FL, Hamilton County, FL, Nassau County, FL, Putnam County, FL, Saint Johns County, FL, Union County, FL, Appling County, GA, Bacon County, GA, Brantley County, GA, Bryan County, GA, Camden County, GA, Charlton County, GA, Chatham County, GA, Clinch County, GA, Echols County, GA, Glynn County, GA, Liberty County, GA, Long County, GA, McIntosh County, GA, Pierce County, GA, Ware County, GA, Wayne County, GA

The radar

The Jacksonville radar (KJAX), 35 km from the middle of the area, began a volume at 12:29 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 nearest sounding before it

Jacksonville, FL (KJAX), launched 12:00Z, 0.5 hours before the alert went out and 34 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1148 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 500 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 91 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.

176 
ACUS11 KWNS 101230
SWOMCD
SPC MCD 101230 
FLZ000-SCZ000-GAZ000-101400-

MESOSCALE DISCUSSION 2245
NWS STORM PREDICTION CENTER NORMAN OK
0730 AM CDT MON OCT 10 2011

AREAS AFFECTED...NE FL...SE GA

CONCERNING...TORNADO WATCH 865...

VALID 101230Z - 101400Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 865 CONTINUES.

AN ISOLATED TORNADO THREAT WILL CONTINUE ACROSS SE GA THIS MORNING.
THE TORNADO THREAT HAS NEARLY ENDED ACROSS NRN FL WHERE WW 865 WILL
BE CLEARED AT 9 AM LOCAL TIME.

SFC ANALYSIS CONTINUES TO SHOW A 1007 MB LOW NEAR LAKE CITY FL.
ABUNDANT LOW-LEVEL MOISTURE IS WRAPPING AROUND THE EAST AND NORTH
SIDE OF THE LOW WHERE SFC DEWPOINTS ARE IN THE LOWER 70S F AND
PRECIPITABLE WATER VALUES ARE ESTIMATED ABOVE 2.0 INCHES. IN
ADDITION...A LOW-LEVEL JET IS LOCATED ACROSS SE GA WHICH IS CREATING
FAVORABLE SHEAR PROFILES FOR ROTATING STORMS. AS ISOLATED ROTATING
CELLS CONTINUE TO DEVELOP OVER SE GA AND MOVE INLAND FROM THE NEARBY
COASTAL WATERS...AN ISOLATED TORNADO OR TWO WILL BE POSSIBLE ACROSS
WW 865. THE SRN EDGE OF THE TORNADO THREAT IS CURRENTLY LOCATED
ALONG THE GA-FL STATE-LINE AND SHOULD GRADUALLY SHIFT NWD WITH TIME.

..BROYLES.. 10/10/2011

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

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

LAT...LON   31898057 32088105 32208107 32178128 32228144 32178169
            31788198 31958225 31978244 31758256 31218267 31208294
            30928295 30778313 30638311 30628326 30408320 30418292
            30238283 29938283 29808260 29548263 29518220 29428214
            29588184 29438170 29338155 29418144 29608150 29718116
            29488109 29528072 30548104 31088090 31538070 31898057

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 10, 3:52 AM EDT	Mesoscale Discussion	SPC	Alachua, Baker, Bradford, Clay, Columbia, Duval and 6 more	83 min
Oct 10, 4:26 AM EDT	Tornado Watch	SPC	Alachua, Baker, Bradford, Clay, Columbia, Duval and 5 more	9 hr
Oct 10, 12:12 PM EDT	Mesoscale Discussion	SPC	Appling, Bacon, Brantley, Bryan, Camden, Charlton and 10 more	63 min

Nearby

Mesoscale Discussions in Georgia, 2011 Mesoscale Discussions in Florida, 2011 Every mesoscale discussion in 2011

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.