Alert archive / Florida / Tornado Watches in 2009

Tornado Watch 114

April 2, 200924 counties in Florida; 6 counties in Georgia

The Storm Prediction Center issued this tornado watch at Apr 2, 2009, 9:47 PM EDT for 24 counties in Florida; 6 counties in Georgia. It was in force for 9 hr.

The area

The outline as issued.

The facts

Issued
Apr 2, 2009, 9:47 PM EDT (01:47 UTC)
Expired
Apr 3, 2009, 7:00 AM EDT
In force
9 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt
All 30 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Citrus County, FL, Clay County, FL, Columbia County, FL, Dixie County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Hamilton County, FL, Hernando County, FL, Lafayette County, FL, Levy County, FL, Madison County, FL, Marion County, FL, Nassau County, FL, Pasco County, FL, Putnam County, FL, Saint Johns County, FL, Sumter County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL, Camden County, GA, Charlton County, GA, Clinch County, GA, Echols County, GA, Glynn County, GA, Ware County, GA

The radar

The Jacksonville radar (KJAX), 64 km from the middle of the area, began a volume at 01:48 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.

What SPC expected

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

Two or more tornadoes
30%
One or more EF2 to EF5 tornadoes
30%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
50%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 2, 10:54 PM EDTSevere Thunderstorm WarningJAXDuval, Nassau51 min
Apr 2, 11:03 PM EDTSevere Thunderstorm WarningJAXBaker, Columbia, Suwannee, Union42 min
Apr 2, 11:19 PM EDTSevere Thunderstorm WarningJAXBaker, Bradford, Clay, Duval, Union56 min
Apr 3, 12:14 AM EDTSevere Thunderstorm WarningJAXSuwannee46 min
Apr 3, 12:20 AM EDTSevere Thunderstorm WarningJAXDuval40 min
Apr 3, 4:35 AM EDTTornado WarningJAXClay, Duval, Saint Johns25 min
Apr 3, 4:58 AM EDTTornado WarningJAXDuval, Saint Johns32 min
Apr 3, 5:56 AM EDTTornado WarningJAXFlagler, Putnam, Saint Johns49 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 00:00Z, 1.8 hours before the alert went out and 66 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 2009-04-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 316 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 00:00Z on 2009-04-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 211 square meters per square second.1939587897117Sfc1 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
316 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
527 m above ground
0-6 km bulk shear
93 kt
0-1 km storm-relative helicity
211 m²/s²
0-3 km storm-relative helicity
379 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 3, 12:27 AM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Citrus, Clay, Columbia and 17 more2 hr
Apr 3, 5:49 AM EDTMesoscale DiscussionSPCFlagler, Marion, Putnam, Saint Johns56 min
Apr 3, 7:07 AM EDTMesoscale DiscussionSPCFlagler, Marion, Putnam, Saint Johns83 min
Apr 3, 10:54 AM EDTMesoscale DiscussionSPCCharlotte, DeSoto, Glades, Hardee, Highlands, Indian River and 4 more2 hr
Apr 2, 10:15 PM EDTMesoscale DiscussionSPCCatoosa, Chattooga, Dade, Floyd, Walker, Whitfield90 min
Apr 2, 11:00 PM EDTMesoscale DiscussionSPCBanks, Barrow, Bartow, Butts, Cherokee, Clarke and 40 more60 min
Apr 2, 11:35 PM EDTSevere Thunderstorm WatchSPCBanks, Barrow, Butts, Cherokee, Clarke, Clayton and 38 more6 hr
Apr 3, 12:50 AM EDTMesoscale DiscussionSPCBanks, Barrow, Bartow, Butts, Carroll, Cherokee and 49 more85 min
Apr 3, 4:47 AM EDTMesoscale DiscussionSPCEffingham, Screven88 min

Nearby

Tornado Watches in Florida, 2009Tornado Watches in Georgia, 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; radar from the NEXRAD Level II archive.