Alert archive / Georgia / Tornado Watches in 2009

Tornado Watch 104

April 2, 200912 counties in Florida; 22 counties in Georgia

The Storm Prediction Center issued this tornado watch at Apr 2, 2009, 8:31 AM EDT for 12 counties in Florida; 22 counties in Georgia. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Apr 2, 2009, 8:31 AM EDT (12:31 UTC)
Expired
Apr 2, 2009, 3:00 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 34 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, Nassau County, FL, Saint Johns County, FL, Suwannee County, FL, Union County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Brantley County, GA, Camden County, GA, Charlton County, GA, Clinch County, GA, Coffee County, GA, Dodge County, GA, Echols County, GA, Glynn County, GA, Jeff Davis County, GA, Laurens County, GA, Montgomery County, GA, Pierce County, GA, Telfair County, GA, Toombs County, GA, Treutlen County, GA, Ware County, GA, Wayne County, GA, Wheeler County, GA, Wilcox County, GA

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
60%
One or more EF2 to EF5 tornadoes
40%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 2, 10:48 AM EDTSevere Thunderstorm WarningJAXCoffee42 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Jacksonville, FL (KJAX), launched 12:00Z, 0.5 hours before the alert went out and 89 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 2009-04-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 785 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 2009-04-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 139 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
785 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
560 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
139 m²/s²
0-3 km storm-relative helicity
411 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.8

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 2, 12:52 AM EDTMesoscale DiscussionSPCBay, Calhoun, Dixie, Franklin, Gadsden, Gulf and 7 more113 min
Apr 2, 6:57 AM EDTMesoscale DiscussionSPCBay, Calhoun, Escambia, Franklin, Gadsden, Gulf and 10 more63 min
Apr 2, 7:29 AM EDTTornado WatchSPCBay, Calhoun, Dixie, Escambia, Franklin, Gadsden and 14 more8 hr
Apr 2, 11:06 AM EDTMesoscale DiscussionSPCBaker, Bay, Calhoun, Columbia, Dixie, Franklin and 16 more54 min
Apr 2, 1:17 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Dixie and 13 more58 min
Apr 2, 2:33 PM EDTTornado WatchSPCEscambia, Okaloosa, Santa Rosa5 hr
Apr 2, 3:00 PM EDTTornado WatchSPCAlachua, Baker, Bay, Bradford, Calhoun, Clay and 23 more7 hr
Apr 2, 4:42 PM EDTMesoscale DiscussionSPCBay, Calhoun, Escambia, Gadsden, Holmes, Jackson and 5 more63 min
Apr 2, 7:28 PM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Duval and 8 more92 min
Apr 2, 4:12 AM EDTMesoscale DiscussionSPCBaldwin, Banks, Barrow, Bartow, Bibb, Bleckley and 70 more63 min
Apr 2, 6:25 PM EDTMesoscale DiscussionSPCBartow, Carroll, Catoosa, Chattooga, Cherokee, Cobb and 20 more95 min
Apr 2, 7:02 PM EDTTornado WatchSPCBartow, Carroll, Catoosa, Chattooga, Dade, Floyd and 8 more7 hr

Nearby

Tornado Watches in Georgia, 2009Tornado Watches in Florida, 2009Every tornado watch in 2009

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.