Alert archive / South Dakota / Areal Flood Warnings in 2021

Areal Flood Warning 7, NWS Aberdeen, SD

August 8, 2021Clark County, Codington County, Grant County, South Dakota

NWS Aberdeen, SD issued this areal flood warning at Aug 8, 2021, 5:02 AM CDT for Clark County, Codington County, Grant County, South Dakota. It was in force for 4 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: Aug 8, 2021, 5:02 AM CDT (10:02 UTC)
Expired: Aug 8, 2021, 9:30 AM CDT
In force: 4 hr
Issued by: NWS Aberdeen, SD
Area: Storm-based polygon
Flood severity: None

Counties Clark County, SD, Codington County, SD, Grant County, SD

The radar

The Aberdeen radar (KABR), 106 km from the middle of the area, began a volume at 10:03 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

Aberdeen, SD (KABR), launched 00:00Z, 10.0 hours before the alert went out and 93 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: 2053 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 1417 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 53 m²/s²
0-3 km storm-relative helicity: 86 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 4.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Aberdeen, SD wrote its last area forecast discussion before this areal flood warning went out at Aug 8, 3:43 AM CDT, 1 hour 19 minutes earlier.

Area forecast discussion, Aug 8, 3:43 AM CDT, 1 hour 19 minutes before

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Hazardous weather outlook, Aug 8, 4:14 AM CDT, 48 minutes before

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In the hours before

Local storm report, Aug 7, 11:07 PM CDT, 5 hours 55 minutes before

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Local storm report, Aug 7, 11:37 PM CDT, 5 hours 25 minutes before

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Local storm report, Aug 8, 1:35 AM CDT, 3 hours 27 minutes before

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The office that day

Everything else NWS Aberdeen, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 7, 7:05 PM CDT	Severe Thunderstorm Warning	ABR	Brown, McPherson	40 min
Aug 7, 7:26 PM CDT	Severe Thunderstorm Warning	ABR	Brown	49 min
Aug 7, 8:09 PM CDT	Special Weather Statement	ABR	Brown	36 min
Aug 7, 8:18 PM CDT	Special Weather Statement	ABR	Brown	27 min
Aug 7, 9:07 PM CDT	Special Weather Statement	ABR	Brown	23 min
Aug 7, 10:09 PM CDT	Special Weather Statement	ABR	Brown	36 min
Aug 7, 10:53 PM CDT	Special Weather Statement	ABR	Spink	37 min
Aug 7, 11:01 PM CDT	Severe Thunderstorm Warning	ABR	Brown, Spink	44 min
Aug 7, 11:25 PM CDT	Severe Thunderstorm Warning	ABR	Brown, Clark, Day, Spink	50 min
Aug 8, 12:56 AM CDT	Severe Thunderstorm Warning	ABR	Clark	49 min
Aug 8, 3:37 AM CDT	Areal Flood Warning	ABR	Clark, Day	5 hr

Nearby

Areal Flood Warnings in South Dakota, 2021 Every areal flood warning in 2021

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.