Alert archive / Alabama / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 151, NWS Birmingham, AL

April 20, 1999Jackson County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at Apr 20, 1999, 1:25 AM CDT for Jackson County, Alabama. 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
Apr 20, 1999, 1:25 AM CDT (06:25 UTC)
Expired
Apr 20, 1999, 2:10 AM CDT
In force
45 min
Issued by
NWS Birmingham, AL
Area
Whole counties

County Jackson County, AL

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 6.4 hours before the alert went out and 209 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, Peachtre/Fal Fld, GA at 00:00Z on 1999-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Peachtre/Fal Fld, GA at 00:00Z on 1999-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2458 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
223 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

Everything else NWS Birmingham, AL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 19, 9:36 PM CDTSevere Thunderstorm WarningBMXMadison34 min
Apr 19, 9:40 PM CDTSevere Thunderstorm WarningBMXMorgan35 min
Apr 19, 10:12 PM CDTSevere Thunderstorm WarningBMXMarshall48 min
Apr 19, 11:27 PM CDTSevere Thunderstorm WarningBMXEtowah33 min
Apr 19, 11:48 PM CDTSevere Thunderstorm WarningBMXCalhoun, Cherokee47 min
Apr 20, 12:52 AM CDTSevere Thunderstorm WarningBMXCullman48 min
Apr 20, 1:12 AM CDTSevere Thunderstorm WarningBMXMadison48 min
Apr 20, 1:29 AM CDTSevere Thunderstorm WarningBMXBlount31 min
Apr 20, 1:56 AM CDTSevere Thunderstorm WarningBMXEtowah, Marshall49 min
Apr 20, 2:42 AM CDTSevere Thunderstorm WarningBMXCherokee48 min

Nearby

Severe Thunderstorm Warnings in Alabama, 1999Every severe thunderstorm warning in 1999

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.