Alert archive / Georgia / Tornado Watches in 2020

Tornado Watch 126

April 20, 202015 counties in Florida; 24 counties in Georgia; 4 counties in South Carolina

The Storm Prediction Center issued this tornado watch at Apr 20, 2020, 2:19 AM EDT for 15 counties in Florida; 24 counties in Georgia; 4 counties in South Carolina. It was in force for 9 hr.

The area

The outline as issued.

The facts

Issued
Apr 20, 2020, 2:19 AM EDT (06:19 UTC)
Expired
Apr 20, 2020, 11:00 AM EDT
In force
9 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
65 kt
All 43 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Clay County, FL, Columbia County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Hamilton County, FL, Marion County, FL, Nassau County, FL, Putnam County, FL, Saint Johns County, FL, Suwannee County, FL, Union County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Brantley County, GA, Bryan County, GA, Bulloch County, GA, Camden County, GA, Candler County, GA, Charlton County, GA, Chatham County, GA, Clinch County, GA, Coffee County, GA, Echols County, GA, Effingham County, GA, Evans County, GA, Glynn County, GA, Jeff Davis County, GA, Liberty County, GA, Long County, GA, McIntosh County, GA, Pierce County, GA, Tattnall County, GA, Ware County, GA, Wayne County, GA, Beaufort County, SC, Charleston County, SC, Colleton County, SC, Jasper County, SC

The radar

The Jacksonville radar (KJAX), 52 km from the middle of the area, began a volume at 06:23 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
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
10%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 20, 2:59 AM EDTSevere Thunderstorm WarningJAXAppling, Atkinson, Bacon, Brantley, Charlton, Clinch and 4 more46 min
Apr 20, 3:17 AM EDTSevere Thunderstorm WarningJAXAppling, Atkinson, Bacon, Clinch, Coffee, Echols and 3 more43 min
Apr 20, 3:35 AM EDTSevere Thunderstorm WarningJAXAppling, Bacon, Brantley, Camden, Charlton, Glynn and 3 more40 min
Apr 20, 3:50 AM EDTSevere Thunderstorm WarningCHSBryan, Liberty, Long40 min
Apr 20, 3:58 AM EDTSevere Thunderstorm WarningJAXAppling, Atkinson, Bacon, Brantley, Clinch, Coffee and 4 more47 min
Apr 20, 4:38 AM EDTSevere Thunderstorm WarningJAXNassau23 min
Apr 20, 5:10 AM EDTSevere Thunderstorm WarningJAXBrantley, Glynn, Wayne24 min
Apr 20, 5:15 AM EDTSevere Thunderstorm WarningCHSBryan, Liberty, McIntosh60 min
Apr 20, 5:34 AM EDTSevere Thunderstorm WarningJAXBrantley, Camden, Glynn30 min
Apr 20, 6:09 AM EDTSevere Thunderstorm WarningJAXNassau33 min
Apr 20, 6:34 AM EDTSevere Thunderstorm WarningJAXColumbia, Gilchrist, Suwannee, Union26 min
Apr 20, 6:54 AM EDTSevere Thunderstorm WarningJAXBaker, Columbia, Suwannee, Union51 min
Apr 20, 7:44 AM EDTSevere Thunderstorm WarningJAXDuval, Saint Johns18 min
Apr 20, 9:22 AM EDTSevere Thunderstorm WarningJAXMarion38 min
Apr 20, 9:54 AM EDTSevere Thunderstorm WarningJAXMarion51 min
Apr 20, 10:10 AM EDTTornado WarningJAXMarion12 min
Apr 20, 10:17 AM EDTTornado WarningJAXMarion8 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, 6.3 hours before the alert went out and 52 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 2020-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 262 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 2020-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 165 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
262 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
1615 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
165 m²/s²
0-3 km storm-relative helicity
227 m²/s²
Significant tornado parameter
0.1
Supercell composite
3.2

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 19, 10:39 PM EDTTornado WatchSPCEscambia, Okaloosa, Santa Rosa5 hr
Apr 19, 10:53 PM EDTMesoscale DiscussionSPCGadsden, Holmes, Jackson, Walton, Washington67 min
Apr 19, 11:13 PM EDTTornado WatchSPCBay, Calhoun, Dixie, Franklin, Gadsden, Gulf and 11 more10 hr
Apr 20, 1:52 AM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Clay, Columbia, Duval and 6 more83 min
Apr 20, 6:19 AM EDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Citrus, Clay, Columbia and 16 more86 min
Apr 20, 7:02 AM EDTSevere Thunderstorm WatchSPCBrevard, Citrus, Hardee, Hernando, Hillsborough, Lake and 11 more8 hr
Apr 20, 8:18 AM EDTMesoscale DiscussionSPCAlachua, Citrus, Flagler, Levy, Marion, Putnam and 2 more87 min
Apr 20, 11:06 AM EDTMesoscale DiscussionSPCBrevard, Hardee, Hernando, Hillsborough, Indian River, Lake and 10 more114 min
Apr 20, 2:00 PM EDTMesoscale DiscussionSPCDeSoto, Hardee, Highlands, Indian River, Manatee, Okeechobee and 4 more90 min
Apr 19, 9:25 PM EDTMesoscale DiscussionSPCBaker, Calhoun, Chattahoochee, Clay, Early, Marion and 6 more65 min

Nearby

Tornado Watches in Georgia, 2020Tornado Watches in Florida, 2020Tornado Watches in South Carolina, 2020Every tornado watch in 2020

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.