⚠️ Severe Thunderstorm Warning – Jasper, IA; Marshall, IA; Poweshiek, IA; Tama, IA – Monday, July 20, 2026

Severe Thunderstorm Warning issued July 20 at 5:48PM CDT until July 20 at 6:45PM CDT by NWS Des Moines IA

Details

SVRDMX

The National Weather Service in Des Moines has issued a

* Severe Thunderstorm Warning for…
Poweshiek County in central Iowa…
Southeastern Marshall County in central Iowa…
Southwestern Tama County in central Iowa…
Northeastern Jasper County in central Iowa…

* Until 645 PM CDT.

* At 547 PM CDT, a severe thunderstorm was located over Gilman, or 10
miles north of Grinnell, moving southeast at 35 mph.

HAZARD…60 mph wind gusts and quarter size hail.

SOURCE…Radar indicated.

IMPACT…Hail damage to vehicles is expected. Expect wind damage
to roofs, siding, and trees.

* Locations impacted include…
Grinnell, Montezuma, Brooklyn, Gilman, Holiday Lake, Malcom,
Montour, Searsboro, Ferguson, Guernsey, and Grinnell Regional
Airport.

This includes Interstate 80 between mile markers 179 and 204.

Instructions

For your protection move to an interior room on the lowest floor of a
building.

A Tornado Watch remains in effect until 1000 PM CDT for central Iowa.

This alert was automatically posted by SkyGuard, MWSC’s severe weather alerting system. Source: National Weather Service.