Alert archive / Iowa / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 244, NWS Des Moines, IA

September 29, 20194 counties in Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Sep 29, 2019, 4:30 PM CDT for 4 counties in Iowa. It was in force for 45 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: Sep 29, 2019, 4:30 PM CDT (21:30 UTC)
Expired: Sep 29, 2019, 5:15 PM CDT
In force: 45 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Calhoun County, IA, Humboldt County, IA, Pocahontas County, IA, Webster County, IA

The radar

The Des Moines radar (KDMX), 111 km from the middle of the area, began a volume at 21:31 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

Omaha, NE (KOAX), launched 12:00Z, 9.5 hours before the alert went out and 213 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: 5 J/kg
Mixed-layer CIN: -226 J/kg
Mixed-layer LCL: 553 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 135 m²/s²
0-3 km storm-relative helicity: 285 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 Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 29, 3:43 PM CDT, 47 minutes earlier.

Area forecast discussion, Sep 29, 3:43 PM CDT, 47 minutes before

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Hazardous weather outlook, Sep 29, 3:51 PM CDT, 39 minutes before

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In the hours before

Local storm report, Sep 29, 10:42 AM CDT, 5 hours 48 minutes before

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Local storm report, Sep 29, 10:43 AM CDT, 5 hours 47 minutes before

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Local storm report, Sep 29, 10:46 AM CDT, 5 hours 44 minutes before

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<body>
  <main class="wrap">
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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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Special weather statement, Sep 29, 4:24 PM CDT, 6 minutes before

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      <h1 id="headline">This service is currently unavailable.</h1>
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        Please try again in a few minutes.
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        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 Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 28, 7:15 PM CDT	Special Weather Statement	DMX	Davis	45 min
Sep 28, 7:32 PM CDT	Special Weather Statement	DMX	Appanoose, Davis, Monroe, Wapello	58 min
Sep 28, 7:48 PM CDT	Flash Flood Warning	DMX	Appanoose, Davis, Monroe, Wapello, Wayne	3 hr
Sep 29, 4:53 AM CDT	Flash Flood Watch	DMX	Appanoose, Clarke, Davis, Decatur, Lucas, Monroe and 5 more	11 hr
Sep 29, 7:51 AM CDT	Flash Flood Warning	DMX	Appanoose, Decatur, Wayne	9 hr
Sep 29, 4:24 PM CDT	Special Weather Statement	DMX	Pocahontas	51 min
Sep 29, 4:30 PM CDT	Areal Flood Warning	DMX	Decatur	21 hr
Sep 29, 4:34 PM CDT	Areal Flood Warning	DMX	Appanoose	21 hr
Sep 29, 5:11 PM CDT	Special Weather Statement	DMX	Wright	49 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2019 Every severe thunderstorm warning in 2019

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.