Alert archive / Iowa / Freeze Warnings in 2024

Freeze Warning 1, NWS Sioux Falls, SD

April 18, 20247 counties in South Dakota; 11 counties in Iowa; 8 counties in Minnesota

NWS Sioux Falls, SD issued this freeze warning at Apr 18, 2024, 2:30 PM CDT for 7 counties in South Dakota; 11 counties in Iowa; 8 counties in Minnesota. It took effect at Apr 19, 2024, 1:00 AM CDT. It was in force for 7 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: Apr 18, 2024, 2:30 PM CDT (19:30 UTC)
In effect from: Apr 19, 2024, 1:00 AM CDT
Expired: Apr 19, 2024, 8:00 AM CDT
In force: 7 hr
Issued by: NWS Sioux Falls, SD

All 26 counties

Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Ida County, IA, Lyon County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Cottonwood County, MN, Jackson County, MN, Lincoln County, MN, Lyon County, MN, Murray County, MN, Nobles County, MN, Pipestone County, MN, Rock County, MN, Clay County, SD, Lincoln County, SD, Minnehaha County, SD, Moody County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 60 km from the middle of the area, began a volume at 19:29 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

Minneapolis, MN (KMPX), launched 12:00Z, 7.5 hours before the alert went out and 256 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: 1365 m above ground
0-6 km bulk shear: 75 kt
0-1 km storm-relative helicity: -14 m²/s²
0-3 km storm-relative helicity: 61 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 freeze warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Sioux Falls, SD wrote its last area forecast discussion before this freeze warning went out at Apr 18, 12:24 PM CDT, 2 hours 6 minutes earlier.

Area forecast discussion, Apr 18, 12:24 PM CDT, 2 hours 6 minutes before

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Hazardous weather outlook, Apr 18, 4:02 AM CDT, 10 hours 28 minutes before

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In the hours before

Local storm report, Apr 18, 11:01 AM CDT, 3 hours 29 minutes before

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Nearby

Freeze Warnings in Iowa, 2024 Freeze Warnings in Minnesota, 2024 Freeze Warnings in South Dakota, 2024 Every freeze warning in 2024

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.