Alert archive / South Dakota / Flash Flood Warnings in 2023

Flash Flood Warning 1, NWS Aberdeen, SD

July 18, 2023Lyman County, South Dakota

NWS Aberdeen, SD issued this flash flood warning at Jul 18, 2023, 10:19 PM CDT for Lyman County, South Dakota. It was in force for 3 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 18, 2023, 10:19 PM CDT (03:19 UTC)
Expired: Jul 19, 2023, 1:15 AM CDT
In force: 3 hr
Issued by: NWS Aberdeen, SD
Area: Storm-based polygon
Flood severity: None

County Lyman County, SD

The radar

The Aberdeen radar (KABR), 207 km from the middle of the area, began a volume at 03:21 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, 3.3 hours before the alert went out and 160 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: 857 J/kg
Mixed-layer CIN: -187 J/kg
Mixed-layer LCL: 1255 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 110 m²/s²
0-3 km storm-relative helicity: 202 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 3.8

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 Aberdeen, SD wrote its last area forecast discussion before this flash flood warning went out at Jul 18, 6:28 PM CDT, 3 hours 51 minutes earlier.

Area forecast discussion, Jul 18, 6:28 PM CDT, 3 hours 51 minutes before

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Hazardous weather outlook, Jul 18, 4:04 PM CDT, 6 hours 15 minutes before

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In the hours before

Local storm report, Jul 18, 6:42 PM CDT, 3 hours 37 minutes before

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Local storm report, Jul 18, 6:44 PM CDT, 3 hours 35 minutes before

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Local storm report, Jul 18, 6:48 PM CDT, 3 hours 31 minutes before

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Local storm report, Jul 18, 6:54 PM CDT, 3 hours 25 minutes before

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Local storm report, Jul 18, 6:57 PM CDT, 3 hours 22 minutes before

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<body>
  <main class="wrap">
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      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
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      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 18, 7:14 PM CDT	Severe Thunderstorm Warning	ABR	Hughes, Lyman, Stanley	61 min
Jul 18, 7:15 PM CDT	Severe Thunderstorm Warning	ABR	Buffalo, Hand, Hughes, Hyde, Lyman	47 min
Jul 18, 7:18 PM CDT	Special Weather Statement	ABR	Hand	27 min
Jul 18, 7:45 PM CDT	Severe Thunderstorm Warning	ABR	Buffalo, Hand, Hyde, Lyman	60 min
Jul 18, 7:50 PM CDT	Special Weather Statement	ABR	Hand	25 min
Jul 18, 8:43 PM CDT	Severe Thunderstorm Warning	ABR	Lyman	62 min
Jul 18, 10:48 PM CDT	Severe Thunderstorm Warning	ABR	Lyman	42 min
Jul 18, 11:14 PM CDT	Severe Thunderstorm Warning	ABR	McPherson	46 min
Jul 19, 12:06 AM CDT	Special Weather Statement	ABR	McPherson	24 min
Jul 19, 1:10 AM CDT	Special Weather Statement	ABR	Brown	20 min
Jul 19, 3:06 PM CDT	Special Weather Statement	ABR	Deuel	24 min

Nearby

Flash Flood Warnings in South Dakota, 2023 Every flash flood warning in 2023

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.