Alert archive / Florida / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 99, NWS Jacksonville, FL

July 4, 2019Duval County, Florida

NWS Jacksonville, FL issued this severe thunderstorm warning at Jul 4, 2019, 3:49 PM EDT for Duval County, Florida. It was in force for 26 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: Jul 4, 2019, 3:49 PM EDT (19:49 UTC)
Expired: Jul 4, 2019, 4:15 PM EDT
In force: 26 min
Issued by: NWS Jacksonville, FL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Duval County, FL

The radar

The Jacksonville radar (KJAX), 17 km from the middle of the area, began a volume at 19:50 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

Cape Canaveral, FL (KXMR), launched 12:00Z, 7.8 hours before the alert went out and 235 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: 443 J/kg
Mixed-layer CIN: -103 J/kg
Mixed-layer LCL: 1277 m above ground
0-6 km bulk shear: 4 kt
0-1 km storm-relative helicity: -2 m²/s²
0-3 km storm-relative helicity: 4 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 Jul 4, 3:13 PM EDT, 36 minutes earlier.

Area forecast discussion, Jul 4, 3:13 PM EDT, 36 minutes before

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In the hours before

Special weather statement, Jul 4, 3:09 PM EDT, 40 minutes before

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Special weather statement, Jul 4, 3:20 PM EDT, 29 minutes before

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Local storm report, Jul 4, 3:23 PM EDT, 26 minutes before

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Special weather statement, Jul 4, 3:28 PM EDT, 21 minutes before

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Special weather statement, Jul 4, 3:34 PM EDT, 15 minutes before

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Special weather statement, Jul 4, 3:38 PM EDT, 11 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
Jul 4, 1:45 PM EDT	Special Weather Statement	JAX	Flagler	30 min
Jul 4, 2:28 PM EDT	Special Weather Statement	JAX	Saint Johns	32 min
Jul 4, 2:45 PM EDT	Special Weather Statement	JAX	Saint Johns	30 min
Jul 4, 2:48 PM EDT	Severe Thunderstorm Warning	JAX	Duval, Saint Johns	27 min
Jul 4, 2:53 PM EDT	Severe Thunderstorm Warning	JAX	Saint Johns	24 min
Jul 4, 2:59 PM EDT	Special Weather Statement	JAX	Flagler	31 min
Jul 4, 3:09 PM EDT	Special Weather Statement	JAX	Duval	36 min
Jul 4, 3:20 PM EDT	Special Weather Statement	JAX	Putnam	25 min
Jul 4, 3:34 PM EDT	Special Weather Statement	JAX	Duval	26 min
Jul 4, 3:38 PM EDT	Special Weather Statement	JAX	Marion	37 min
Jul 4, 4:13 PM EDT	Special Weather Statement	JAX	Duval	32 min
Jul 4, 4:29 PM EDT	Special Weather Statement	JAX	Clay	31 min
Jul 4, 4:56 PM EDT	Special Weather Statement	JAX	Marion	34 min
Jul 4, 5:05 PM EDT	Areal Flood Advisory	JAX	Clay	85 min
Jul 4, 5:12 PM EDT	Special Weather Statement	JAX	Nassau	33 min
Jul 4, 5:21 PM EDT	Special Weather Statement	JAX	Alachua	24 min
Jul 4, 5:25 PM EDT	Severe Thunderstorm Warning	JAX	Nassau	35 min
Jul 4, 5:29 PM EDT	Special Weather Statement	JAX	Union	31 min
Jul 4, 5:52 PM EDT	Special Weather Statement	JAX	Gilchrist	38 min
Jul 4, 5:56 PM EDT	Areal Flood Advisory	JAX	Alachua	94 min
Jul 4, 6:07 PM EDT	Special Weather Statement	JAX	Baker	23 min
Jul 4, 6:18 PM EDT	Special Weather Statement	JAX	Gilchrist	27 min
Jul 4, 6:40 PM EDT	Special Weather Statement	JAX	Suwannee	65 min
Jul 4, 7:11 PM EDT	Areal Flood Advisory	JAX	Columbia, Hamilton	2 hr
Jul 4, 7:13 PM EDT	Areal Flood Advisory	JAX	Columbia	92 min
Jul 4, 3:28 PM EDT	Special Weather Statement	JAX	Appling	32 min
Jul 4, 4:15 PM EDT	Special Weather Statement	JAX	Ware	30 min
Jul 4, 5:22 PM EDT	Special Weather Statement	JAX	Charlton	23 min
Jul 4, 5:49 PM EDT	Special Weather Statement	JAX	Charlton	41 min

Nearby

Severe Thunderstorm Warnings in Florida, 2019 Every severe thunderstorm warning in 2019

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.