Alert archive / Iowa / Flash Flood Watches in 2009

Flash Flood Watch 3, NWS Des Moines, IA

March 9, 200910 counties in Iowa

NWS Des Moines, IA issued this flash flood watch at Mar 9, 2009, 3:45 AM CDT for 10 counties in Iowa. It took effect at Mar 9, 2009, 7:00 PM CDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued: Mar 9, 2009, 3:45 AM CDT (08:45 UTC)
In effect from: Mar 9, 2009, 7:00 PM CDT
Expired: Mar 10, 2009, 3:59 AM CDT
In force: 9 hr
Issued by: NWS Des Moines, IA
Flood severity: None

Counties Appanoose County, IA, Davis County, IA, Decatur County, IA, Lucas County, IA, Mahaska County, IA, Marion County, IA, Monroe County, IA, Poweshiek County, IA, Wapello County, IA, Wayne County, IA

The radar

The Des Moines radar (KDMX), 101 km from the middle of the area, began a volume at 08:44 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 00:00Z, 8.8 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 594 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 110 m²/s²
0-3 km storm-relative helicity: 81 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 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 Mar 9, 3:24 AM CDT, 21 minutes earlier.

Area forecast discussion, Mar 9, 3:24 AM CDT, 21 minutes before

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Hazardous weather outlook, Mar 8, 2:31 PM CDT, 13 hours 14 minutes before

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        The site you requested is temporarily down for maintenance or an unexpected outage.
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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
Mar 8, 9:15 PM CDT	River Flood Warning	DMX	Marshall	15 hr

Nearby

Flash Flood Watches in Iowa, 2009 Every flash flood watch in 2009

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.