Alert archive / Alabama / Flash Flood Warnings in 2020

Flash Flood Warning 18, NWS Huntsville, AL

July 1, 2020Colbert County, Franklin County, Lauderdale County, Alabama

NWS Huntsville, AL issued this flash flood warning at Jul 1, 2020, 11:12 AM CDT for Colbert County, Franklin County, Lauderdale County, Alabama. It was in force for 2 hr. 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 1, 2020, 11:12 AM CDT (16:12 UTC)
Expired: Jul 1, 2020, 1:38 PM CDT
In force: 2 hr
Issued by: NWS Huntsville, AL
Area: Storm-based polygon
Flood severity: None

Counties Colbert County, AL, Franklin County, AL, Lauderdale County, AL

The radar

The Columbus AFB radar (KGWX), 101 km from the middle of the area, began a volume at 16:16 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

Birmingham, AL (KBMX), launched 12:00Z, 4.2 hours before the alert went out and 190 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: 829 J/kg
Mixed-layer CIN: -52 J/kg
Mixed-layer LCL: 911 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 110 m²/s²
0-3 km storm-relative helicity: 162 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 2.3

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Jul 1, 10:01 AM CDT, 1 hour 11 minutes earlier.

Area forecast discussion, Jul 1, 10:01 AM CDT, 1 hour 11 minutes before

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Hazardous weather outlook, Jul 1, 4:30 AM CDT, 6 hours 42 minutes before

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    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 30, 7:07 PM CDT	Special Weather Statement	HUN	DeKalb	38 min
Jun 30, 7:12 PM CDT	Special Weather Statement	HUN	Lawrence	48 min
Jun 30, 7:49 PM CDT	Special Weather Statement	HUN	Lawrence	41 min
Jun 30, 8:15 PM CDT	Special Weather Statement	HUN	Cullman	30 min
Jun 30, 8:35 PM CDT	Special Weather Statement	HUN	Cullman	40 min
Jun 30, 11:41 PM CDT	Special Weather Statement	HUN	Colbert, Lauderdale	49 min
Jul 1, 12:10 AM CDT	Special Weather Statement	HUN	Lauderdale	50 min
Jul 1, 12:30 AM CDT	Special Weather Statement	HUN	Franklin, Lawrence	30 min
Jul 1, 12:58 AM CDT	Special Weather Statement	HUN	Lawrence, Morgan	32 min
Jul 1, 3:46 AM CDT	Areal Flood Warning	HUN	Colbert, Lauderdale	5 hr
Jul 1, 10:29 AM CDT	Areal Flood Warning	HUN	Colbert, Franklin, Lauderdale, Lawrence	3 hr
Jul 1, 12:23 PM CDT	Special Weather Statement	HUN	Franklin	37 min
Jul 1, 1:31 PM CDT	Areal Flood Warning	HUN	Colbert, Franklin, Lauderdale, Lawrence	3 hr
Jul 1, 4:30 PM CDT	Flash Flood Watch	HUN	Colbert, Franklin, Lauderdale, Lawrence	4 hr
Jul 1, 6:03 PM CDT	Special Weather Statement	HUN	Lauderdale	27 min
Jul 1, 6:28 PM CDT	Special Weather Statement	HUN	Colbert, Franklin, Lauderdale	47 min

Nearby

Flash Flood Warnings in Alabama, 2020 Every flash flood 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.