Alert archive / Iowa / Flash Flood Watches in 2018
Flash Flood Watch 11, NWS Des Moines, IA
NWS Des Moines, IA issued this flash flood watch at Sep 5, 2018, 7:12 AM CDT for 19 counties in Iowa. It was in force for 20 hr.
The area
The counties it named.
The facts
- Issued
- Sep 5, 2018, 7:12 AM CDT (12:12 UTC)
- Expired
- Sep 6, 2018, 3:38 AM CDT
- In force
- 20 hr
- Issued by
- NWS Des Moines, IA
- Flood severity
- None
Counties Adair County, IA, Adams County, IA, Appanoose County, IA, Clarke County, IA, Davis County, IA, Decatur County, IA, Jasper County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Monroe County, IA, Poweshiek County, IA, Ringgold County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA
The radar
The Des Moines radar (KDMX), 75 km from the middle of the area, began a volume at 12:12 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
Davenport, (KDVN), launched 12:00Z, 0.2 hours before the alert went out and 255 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.
- Mixed-layer CAPE
- 152 J/kg
- Mixed-layer CIN
- -61 J/kg
- Mixed-layer LCL
- 981 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 22 m²/s²
- 0-3 km storm-relative helicity
- 30 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this flash flood watch 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 flash flood watch went out at Sep 5, 6:43 AM CDT, 29 minutes earlier.
Area forecast discussion, Sep 5, 6:43 AM CDT, 29 minutes before
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</html>Hazardous weather outlook, Sep 5, 4:43 AM CDT, 2 hours 29 minutes before
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</head>
<body>
<main class="wrap">
<section class="card" role="status" aria-live="polite">
<div class="status" id="status">Temporary Notice</div>
<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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If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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</html>The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 4, 10:44 PM CDT | River Flood Warning | DMX | Cerro Gordo, Floyd, Worth | 11 hr |
| Sep 5, 6:12 AM CDT | Flash Flood Warning | DMX | Franklin | 4 hr |
| Sep 5, 9:49 AM CDT | Areal Flood Warning | DMX | Butler, Franklin, Wright | 6 hr |
| Sep 5, 10:15 AM CDT | River Flood Warning | DMX | Marshall | 4 days |
| Sep 5, 10:15 AM CDT | River Flood Warning | DMX | Black Hawk, Bremer, Butler | 4 days |
| Sep 5, 11:07 AM CDT | Flash Flood Warning | DMX | Jasper, Mahaska, Marion, Poweshiek | 4 hr |
| Sep 5, 12:08 PM CDT | Flash Flood Warning | DMX | Adams, Ringgold, Taylor, Union | 3 hr |
| Sep 5, 3:46 PM CDT | Areal Flood Warning | DMX | Butler, Franklin, Wright | 24 hr |
| Sep 5, 3:53 PM CDT | Areal Flood Warning | DMX | Mahaska, Poweshiek | 24 hr |
Nearby
Flash Flood Watches in Iowa, 2018Every flash flood watch in 2018
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.