Alert archive / South Dakota / Areal Flood Warnings in 2021

Areal Flood Warning 5, NWS Aberdeen, SD

August 7, 2021Codington County, Deuel County, South Dakota

NWS Aberdeen, SD issued this areal flood warning at Aug 7, 2021, 4:35 AM CDT for Codington County, Deuel 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 7, 2021, 4:35 AM CDT (09:35 UTC)
Expired: Aug 7, 2021, 8:45 AM CDT
In force: 4 hr
Issued by: NWS Aberdeen, SD
Area: Storm-based polygon
Flood severity: None

Counties Codington County, SD, Deuel County, SD

The radar

The Aberdeen radar (KABR), 133 km from the middle of the area, began a volume at 09:34 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, 9.6 hours before the alert went out and 116 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: 466 J/kg
Mixed-layer CIN: -132 J/kg
Mixed-layer LCL: 1480 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 113 m²/s²
0-3 km storm-relative helicity: 173 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 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 7, 3:54 AM CDT, 41 minutes earlier.

Area forecast discussion, Aug 7, 3:54 AM CDT, 41 minutes before

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Hazardous weather outlook, Aug 7, 3:59 AM CDT, 36 minutes before

Hazardous Weather Outlook
National Weather Service Aberdeen SD
359 AM CDT Sat Aug 7 2021

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-080900-
Traverse-Big Stone-Corson-Campbell-McPherson-Brown-Marshall-Roberts-
Walworth-Edmunds-Day-Dewey-Potter-Faulk-Spink-Clark-Codington-Grant-
Hamlin-Deuel-Stanley-Sully-Hughes-Hyde-Hand-Jones-Lyman-Buffalo-
359 AM CDT Sat Aug 7 2021 /259 AM MDT Sat Aug 7 2021/

This Hazardous Weather Outlook is for west central Minnesota,
central South Dakota, north central South Dakota and northeast
South Dakota.

.DAY ONE...Today and tonight.

Showers and thunderstorms are possible this evening. Some of these
may be strong to severe mainly across eastern South Dakota and west
central Minnesota. Main threats will be large hail, damaging winds,
and heavy rain. However, an isolated tornado cannot be ruled out.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

The next chance for thunderstorms looks to be Monday night into
Tuesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Weather spotters are
encouraged to submit reports to the National Weather Service in
Aberdeen. The public can submit reports on our web page, Facebook
page, or our Twitter feed.

In the hours before

Local storm report, Aug 6, 11:13 PM CDT, 5 hours 22 minutes before

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Local storm report, Aug 6, 11:38 PM CDT, 4 hours 57 minutes before

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Local storm report, Aug 7, 12:01 AM CDT, 4 hours 34 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 6, 9:49 PM CDT	Special Weather Statement	ABR	Jones, Stanley	41 min
Aug 6, 11:07 PM CDT	Severe Thunderstorm Warning	ABR	Buffalo, Lyman	38 min
Aug 6, 11:29 PM CDT	Severe Thunderstorm Warning	ABR	Buffalo, Hand, Hyde, Lyman	46 min
Aug 7, 12:10 AM CDT	Severe Thunderstorm Warning Considerable damage threat	ABR	Faulk, Hand, Hyde, Spink	50 min
Aug 7, 6:39 PM CDT	Severe Thunderstorm Warning	ABR	Brown, McPherson	51 min

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.