Alert archive / Iowa / Ice Storm Warnings in 2023

Ice Storm Warning 2, NWS Des Moines, IA

February 21, 20239 counties in Iowa

NWS Des Moines, IA issued this ice storm warning at Feb 21, 2023, 2:17 PM CST for 9 counties in Iowa. It took effect at Feb 22, 2023, 6:00 AM CST. It was in force for 21 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: Feb 21, 2023, 2:17 PM CST (20:17 UTC)
In effect from: Feb 22, 2023, 6:00 AM CST
Expired: Feb 23, 2023, 2:55 AM CST
In force: 21 hr
Issued by: NWS Des Moines, IA

Counties Black Hawk County, IA, Bremer County, IA, Butler County, IA, Franklin County, IA, Grundy County, IA, Hardin County, IA, Marshall County, IA, Story County, IA, Tama County, IA

The radar

The Des Moines radar (KDMX), 104 km from the middle of the area, began a volume at 20:23 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, 8.3 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: 1095 m above ground
0-6 km bulk shear: 86 kt
0-1 km storm-relative helicity: 84 m²/s²
0-3 km storm-relative helicity: 217 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 ice storm 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 ice storm warning went out at Feb 21, 5:39 AM CST, 8 hours 38 minutes earlier.

Area forecast discussion, Feb 21, 5:39 AM CST, 8 hours 38 minutes before

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Hazardous weather outlook, Feb 21, 2:55 AM CST, 11 hours 22 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
Feb 21, 2:47 AM CST	Winter Storm Warning	DMX	Cerro Gordo, Emmet, Hancock, Humboldt, Kossuth, Palo Alto and 4 more	57 hr
Feb 21, 2:47 AM CST	Winter Weather Advisory	DMX	Adair, Audubon, Black Hawk, Boone, Bremer, Butler and 23 more	57 hr

Nearby

Ice Storm Warnings in Iowa, 2023 Every ice storm 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.