Alert archive / Michigan / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 96, NWS Detroit, MI

July 21, 2026Saint Clair County, Sanilac County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Jul 21, 2026, 12:29 PM EDT for Saint Clair County, Sanilac County, Michigan. It was in force for 61 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 21, 2026, 12:29 PM EDT (16:29 UTC)
Expired: Jul 21, 2026, 1:30 PM EDT
In force: 61 min
Issued by: NWS Detroit, MI
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Saint Clair County, MI, Sanilac County, MI

The radar

The Detroit radar (KDTX), 86 km from the middle of the area, began a volume at 16:31 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

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 4.5 hours before the alert went out and 323 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: 300 J/kg
Mixed-layer CIN: -122 J/kg
Mixed-layer LCL: 1133 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 162 m²/s²
0-3 km storm-relative helicity: 153 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.7

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Detroit, MI wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 21, 10:46 AM EDT, 1 hour 43 minutes earlier.

Area forecast discussion, Jul 21, 10:46 AM EDT, 1 hour 43 minutes before

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Hazardous weather outlook, Jul 21, 9:35 AM EDT, 2 hours 54 minutes before

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In the hours before

Special weather statement, Jul 21, 11:16 AM EDT, 1 hour 13 minutes before

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Special weather statement, Jul 21, 11:29 AM EDT, 1 hour before

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The office that day

Everything else NWS Detroit, MI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 21, 3:22 AM EDT	Beach Hazards Statement	DTX	Huron	43 hr
Jul 21, 6:27 AM EDT	Special Weather Statement	DTX	Lenawee	33 min
Jul 21, 11:16 AM EDT	Special Weather Statement	DTX	Tuscola	29 min
Jul 21, 11:29 AM EDT	Special Weather Statement	DTX	Tuscola	31 min
Jul 21, 11:39 AM EDT	Severe Thunderstorm Warning	DTX	Lapeer, Sanilac, Tuscola	66 min
Jul 21, 12:03 PM EDT	Special Marine Warning	DTX		39 min
Jul 21, 12:05 PM EDT	Special Marine Warning	DTX		85 min
Jul 21, 12:34 PM EDT	Special Weather Statement	DTX	Midland	26 min
Jul 21, 12:57 PM EDT	Special Weather Statement	DTX	Saginaw	33 min
Jul 21, 12:58 PM EDT	Special Weather Statement	DTX	Tuscola	32 min
Jul 21, 12:59 PM EDT	Special Marine Warning	DTX		40 min
Jul 21, 1:03 PM EDT	Severe Thunderstorm Warning	DTX	Bay, Midland, Saginaw	57 min
Jul 21, 1:11 PM EDT	Special Marine Warning	DTX		79 min
Jul 21, 1:22 PM EDT	Severe Thunderstorm Warning	DTX	Saint Clair	11 min
Jul 21, 2:40 PM EDT	Special Marine Warning	DTX		22 min
Jul 21, 2:40 PM EDT	Special Weather Statement	DTX	Lapeer	35 min
Jul 21, 2:42 PM EDT	Special Weather Statement	DTX	Saint Clair	33 min

Nearby

Severe Thunderstorm Warnings in Michigan, 2026 Every severe thunderstorm warning in 2026

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.