Alert archive / Florida / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 127, NWS Tallahassee, FL

May 20, 20204 counties in Florida

NWS Tallahassee, FL issued this severe thunderstorm warning at May 20, 2020, 9:15 AM CDT for 4 counties in Florida. It was in force for 45 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: May 20, 2020, 9:15 AM CDT (14:15 UTC)
Expired: May 20, 2020, 10:00 AM CDT
In force: 45 min
Issued by: NWS Tallahassee, FL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Bay County, FL, Calhoun County, FL, Gadsden County, FL, Liberty County, FL

The radar

The Tallahassee radar (KTLH), 72 km from the middle of the area, began a volume at 14:20 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

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 2.3 hours before the alert went out and 75 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: 5 J/kg
Mixed-layer CIN: -265 J/kg
Mixed-layer LCL: 1349 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 140 m²/s²
0-3 km storm-relative helicity: 217 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.0

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 Tallahassee, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at May 20, 9:10 AM CDT, 5 minutes earlier.

Area forecast discussion, May 20, 9:10 AM CDT, 5 minutes before

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In the hours before

Special weather statement, May 20, 5:26 AM CDT, 3 hours 49 minutes before

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Special weather statement, May 20, 6:36 AM CDT, 2 hours 39 minutes before

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Special weather statement, May 20, 7:48 AM CDT, 1 hour 27 minutes before

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Special weather statement, May 20, 8:36 AM CDT, 39 minutes before

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Special weather statement, May 20, 9:02 AM CDT, 13 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
May 20, 8:36 AM CDT	Special Weather Statement	TAE	Calhoun	24 min
May 20, 9:02 AM CDT	Special Weather Statement	TAE	Calhoun	43 min
May 20, 9:28 AM CDT	Areal Flood Advisory	TAE	Bay, Calhoun, Liberty	2 hr
May 20, 10:14 AM CDT	Special Weather Statement	TAE	Calhoun	46 min
May 20, 10:44 AM CDT	Special Weather Statement	TAE	Liberty	46 min
May 20, 11:26 AM CDT	Special Weather Statement	TAE	Liberty	49 min
May 20, 12:14 PM CDT	Special Weather Statement	TAE	Liberty, Wakulla	61 min
May 20, 1:11 PM CDT	Special Weather Statement	TAE	Wakulla	49 min
May 20, 1:15 PM CDT	Special Marine Warning	TAE		60 min
May 20, 3:28 PM CDT	Special Weather Statement	TAE	Wakulla	47 min
May 20, 3:31 PM CDT	Special Marine Warning	TAE		59 min
May 20, 4:25 PM CDT	Special Marine Warning	TAE		35 min
May 20, 5:28 PM CDT	Special Weather Statement	TAE	Jefferson	47 min
May 20, 5:33 PM CDT	Severe Thunderstorm Warning	TAE	Jefferson, Leon, Madison	42 min
May 20, 6:38 PM CDT	Severe Thunderstorm Warning	TAE	Jefferson, Madison	16 min
May 20, 5:26 AM CDT	Special Weather Statement	TAE	Baker, Calhoun, Dougherty, Mitchell, Worth	64 min
May 20, 6:36 AM CDT	Special Weather Statement	TAE	Cook, Tift	54 min
May 20, 7:48 AM CDT	Special Weather Statement	TAE	Mitchell	27 min
May 20, 6:34 PM CDT	Special Weather Statement	TAE	Lowndes	41 min

Nearby

Severe Thunderstorm Warnings in Florida, 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.