Alert archive / Alabama / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 103, NWS Huntsville, AL

August 27, 2020Jackson County, Alabama; Franklin County, Tennessee

NWS Huntsville, AL issued this severe thunderstorm warning at Aug 27, 2020, 5:04 PM CDT for Jackson County, Alabama; Franklin County, Tennessee. 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: Aug 27, 2020, 5:04 PM CDT (22:04 UTC)
Expired: Aug 27, 2020, 5:30 PM CDT
In force: 26 min
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Hail: 0.88 in
Wind: 60.0 mph

Counties Jackson County, AL, Franklin County, TN

The radar

The Northeast Alabama radar (KHTX), 5 km from the middle of the area, began a volume at 22:06 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

Nashville Metro, TN (KBNA), launched 12:00Z, 10.1 hours before the alert went out and 139 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: 1006 J/kg
Mixed-layer CIN: -46 J/kg
Mixed-layer LCL: 1007 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 38 m²/s²
0-3 km storm-relative helicity: 35 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 Huntsville, AL wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 27, 3:30 PM CDT, 1 hour 34 minutes earlier.

Area forecast discussion, Aug 27, 3:30 PM CDT, 1 hour 34 minutes before

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Hazardous weather outlook, Aug 27, 4:19 PM CDT, 45 minutes before

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In the hours before

Special weather statement, Aug 27, 3:53 PM CDT, 1 hour 11 minutes before

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Special weather statement, Aug 27, 3:59 PM CDT, 1 hour 5 minutes before

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Special weather statement, Aug 27, 4:11 PM CDT, 53 minutes before

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Special weather statement, Aug 27, 4:27 PM CDT, 37 minutes before

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Special weather statement, Aug 27, 4:30 PM CDT, 34 minutes before

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Special weather statement, Aug 27, 4:58 PM CDT, 6 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 27, 3:16 PM CDT	Special Weather Statement	HUN	Franklin	44 min
Aug 27, 3:21 PM CDT	Severe Thunderstorm Warning	HUN	Limestone, Madison	24 min
Aug 27, 3:30 PM CDT	Special Weather Statement	HUN	Lawrence	30 min
Aug 27, 3:36 PM CDT	Special Weather Statement	HUN	Franklin	24 min
Aug 27, 3:40 PM CDT	Special Weather Statement	HUN	Lawrence	50 min
Aug 27, 3:53 PM CDT	Special Weather Statement	HUN	DeKalb	37 min
Aug 27, 3:59 PM CDT	Special Weather Statement	HUN	Colbert, Lauderdale	31 min
Aug 27, 4:11 PM CDT	Special Weather Statement	HUN	DeKalb, Jackson	49 min
Aug 27, 4:18 PM CDT	Severe Thunderstorm Warning	HUN	DeKalb, Jackson	27 min
Aug 27, 4:27 PM CDT	Special Weather Statement	HUN	Limestone	33 min
Aug 27, 4:30 PM CDT	Special Weather Statement	HUN	Lauderdale	30 min
Aug 27, 4:58 PM CDT	Special Weather Statement	HUN	Jackson	47 min
Aug 27, 6:12 PM CDT	Special Weather Statement	HUN	Madison	33 min
Aug 27, 6:26 PM CDT	Special Weather Statement	HUN	Madison	49 min
Aug 27, 5:32 PM CDT	Special Weather Statement	HUN	Franklin	28 min
Aug 27, 5:52 PM CDT	Special Weather Statement	HUN	Franklin	38 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2020 Severe Thunderstorm Warnings in Tennessee, 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.