Alert archive / Florida / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 212, NWS Jacksonville, FL

August 30, 2018Baker County, Duval County, Nassau County, Florida; Charlton County, Georgia

NWS Jacksonville, FL issued this severe thunderstorm warning at Aug 30, 2018, 2:18 PM EDT for Baker County, Duval County, Nassau County, Florida; Charlton County, Georgia. It was in force for 22 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: Aug 30, 2018, 2:18 PM EDT (18:18 UTC)
Expired: Aug 30, 2018, 2:40 PM EDT
In force: 22 min
Issued by: NWS Jacksonville, FL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Baker County, FL, Duval County, FL, Nassau County, FL, Charlton County, GA

The radar

The Jacksonville radar (KJAX), 25 km from the middle of the area, began a volume at 18:20 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, 6.3 hours before the alert went out and 25 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: 1520 J/kg
Mixed-layer CIN: -39 J/kg
Mixed-layer LCL: 808 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 44 m²/s²
0-3 km storm-relative helicity: 92 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 Aug 29, 3:11 PM EDT, 23 hours 7 minutes earlier.

Area forecast discussion, Aug 29, 3:11 PM EDT, 23 hours 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
Aug 30, 12:49 PM EDT	Special Weather Statement	JAX	Alachua, Bradford	26 min
Aug 30, 1:18 PM EDT	Special Weather Statement	JAX	Baker, Bradford, Union	27 min
Aug 30, 1:43 PM EDT	Special Weather Statement	JAX	Baker, Bradford, Union	17 min
Aug 30, 1:57 PM EDT	Special Weather Statement	JAX	Baker, Union	33 min
Aug 30, 2:11 PM EDT	Special Weather Statement	JAX	Baker	49 min
Aug 30, 2:38 PM EDT	Areal Flood Advisory	JAX	Bradford	3 hr
Aug 30, 2:40 PM EDT	Special Weather Statement	JAX	Nassau	50 min
Aug 30, 3:11 PM EDT	Areal Flood Advisory	JAX	Alachua	2 hr
Aug 30, 3:16 PM EDT	Special Weather Statement	JAX	Nassau	29 min
Aug 30, 3:22 PM EDT	Areal Flood Advisory	JAX	Nassau	113 min
Aug 30, 3:39 PM EDT	Areal Flood Advisory	JAX	Nassau	2 hr
Aug 30, 4:47 PM EDT	Areal Flood Advisory	JAX	Putnam	118 min
Aug 30, 2:28 PM EDT	Special Weather Statement	JAX	Charlton	47 min
Aug 30, 2:47 PM EDT	Special Weather Statement	JAX	Ware	28 min
Aug 30, 2:57 PM EDT	Special Weather Statement	JAX	Wayne	33 min
Aug 30, 3:32 PM EDT	Special Weather Statement	JAX	Wayne	28 min
Aug 30, 4:19 PM EDT	Special Weather Statement	JAX	Pierce	41 min
Aug 30, 4:46 PM EDT	Areal Flood Advisory	JAX	Brantley, Pierce, Wayne	119 min
Aug 30, 4:56 PM EDT	Areal Flood Advisory	JAX	Appling	2 hr
Aug 30, 4:59 PM EDT	Special Weather Statement	JAX	Camden	31 min

Nearby

Severe Thunderstorm Warnings in Florida, 2018 Severe Thunderstorm Warnings in Georgia, 2018 Every severe thunderstorm warning in 2018

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.