Alert archive / Florida / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 85, NWS Tampa Bay, FL

August 19, 2009Levy County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Aug 19, 2009, 4:59 PM EDT for Levy County, Florida. It was in force for 31 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 19, 2009, 4:59 PM EDT (20:59 UTC)
Expired
Aug 19, 2009, 5:30 PM EDT
In force
31 min
Issued by
NWS Tampa Bay, FL
Area
Storm-based polygon

County Levy County, FL

The radar

The Jacksonville radar (KJAX), 170 km from the middle of the area, began a volume at 21:01 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, 9.0 hours before the alert went out and 192 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, Tallahassee Rgnl, FL at 12:00Z on 2009-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2246 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, Tallahassee Rgnl, FL at 12:00Z on 2009-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 26 square meters per square second.1939Sfc1 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
2246 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
495 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
26 m²/s²
0-3 km storm-relative helicity
42 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 8:00 PM EDTSpecial Weather StatementTBWLee45 min
Aug 19, 4:33 PM EDTSpecial Weather StatementTBWCharlotte, DeSoto42 min
Aug 19, 4:48 PM EDTSpecial Weather StatementTBWLevy42 min
Aug 19, 5:49 PM EDTSpecial Weather StatementTBWManatee41 min
Aug 19, 6:11 PM EDTSpecial Marine WarningTBW34 min
Aug 19, 6:20 PM EDTSpecial Weather StatementTBWPinellas40 min
Aug 19, 6:52 PM EDTAreal Flood AdvisoryTBWPinellas3 hr
Aug 19, 7:24 PM EDTSpecial Weather StatementTBWPinellas51 min

Nearby

Severe Thunderstorm Warnings in Florida, 2009Every severe thunderstorm warning in 2009

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.