Alert archive / Florida / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 236, NWS Jacksonville, FL

December 24, 20207 counties in Florida; Camden County, Charlton County, Glynn County, Georgia

NWS Jacksonville, FL issued this severe thunderstorm warning at Dec 24, 2020, 6:28 PM EST for 7 counties in Florida; Camden County, Charlton County, Glynn County, Georgia. It was in force for 62 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Dec 24, 2020, 6:28 PM EST (23:28 UTC)
Expired: Dec 24, 2020, 7:30 PM EST
In force: 62 min
Issued by: NWS Jacksonville, FL
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Baker County, FL, Bradford County, FL, Clay County, FL, Duval County, FL, Nassau County, FL, Putnam County, FL, Saint Johns County, FL, Camden County, GA, Charlton County, GA, Glynn County, GA

The radar

The Jacksonville radar (KJAX), 17 km from the middle of the area, began a volume at 23:26 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

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 11.5 hours before the alert went out and 238 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 944 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 346 m²/s²
0-3 km storm-relative helicity: 416 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Jacksonville, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at Dec 24, 5:52 PM EST, 36 minutes earlier.

Area forecast discussion, Dec 24, 5:52 PM EST, 36 minutes before

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In the hours before

Local storm report, Dec 24, 5:24 PM EST, 1 hour 4 minutes before

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Local storm report, Dec 24, 5:25 PM EST, 1 hour 3 minutes before

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Local storm report, Dec 24, 5:29 PM EST, 59 minutes before

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Local storm report, Dec 24, 6:06 PM EST, 22 minutes before

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Special weather statement, Dec 24, 6:19 PM EST, 9 minutes before

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Local storm report, Dec 24, 6:21 PM EST, 7 minutes before

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The office that day

Everything else NWS Jacksonville, FL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 24, 3:32 AM EST	Gale Warning	JAX		35 hr
Dec 24, 3:34 AM EST	Rip Current Statement	JAX	Duval, Flagler, Nassau	10 hr
Dec 24, 3:36 AM EST	Freeze Watch	JAX	Duval, Flagler, Nassau	23 hr
Dec 24, 3:36 AM EST	Hard Freeze Watch	JAX	Alachua, Baker, Bradford, Gilchrist, Marion, Nassau and 2 more	23 hr
Dec 24, 1:41 PM EST	Wind Chill Advisory	JAX	Alachua, Baker, Bradford, Duval, Flagler, Gilchrist and 4 more	19 hr
Dec 24, 1:50 PM EST	Freeze Warning	JAX	Alachua, Baker, Bradford, Gilchrist, Nassau, Suwannee and 1 more	19 hr
Dec 24, 4:02 PM EST	Severe Thunderstorm Warning	JAX	Hamilton	43 min
Dec 24, 4:18 PM EST	Special Weather Statement	JAX	Suwannee	42 min
Dec 24, 4:39 PM EST	Severe Thunderstorm Warning	JAX	Baker, Columbia, Hamilton, Suwannee	66 min
Dec 24, 5:24 PM EST	Special Weather Statement	JAX	Alachua, Gilchrist, Union	51 min
Dec 24, 5:42 PM EST	Severe Thunderstorm Warning	JAX	Alachua, Baker, Bradford, Clay, Columbia, Duval and 3 more	48 min
Dec 24, 6:08 PM EST	Severe Thunderstorm Warning	JAX	Alachua, Putnam	37 min
Dec 24, 6:19 PM EST	Special Weather Statement	JAX	Marion	41 min
Dec 24, 6:31 PM EST	Special Marine Warning	JAX		89 min
Dec 24, 6:48 PM EST	Special Weather Statement	JAX	Putnam	42 min
Dec 24, 3:25 PM EST	Special Weather Statement	JAX	Atkinson, Coffee, Jeff Davis	65 min
Dec 24, 4:25 PM EST	Special Weather Statement	JAX	Appling, Atkinson, Bacon, Coffee, Jeff Davis, Pierce	50 min
Dec 24, 5:14 PM EST	Special Weather Statement	JAX	Brantley, Pierce, Wayne	46 min
Dec 24, 5:33 PM EST	Severe Thunderstorm Warning	JAX	Brantley, Camden, Charlton, Glynn, Pierce, Ware and 1 more	57 min

Nearby

Severe Thunderstorm Warnings in Florida, 2020 Severe Thunderstorm Warnings in Georgia, 2020 Every severe thunderstorm warning 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.