The passage of a strong cold front produced severe thunderstorms over nearshore portions of Lake Superior on the afternoon of the 20th.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS MQT wrote it up.
The passage of a strong cold front produced severe thunderstorms over nearshore portions of Lake Superior on the afternoon of the 20th.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Marquette, MI wrote its last area forecast discussion before the first event at May 20, 6:30 AM EST, 5 hours 45 minutes earlier.
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</html>The Marquette radar (KMQT), 116 km away, was scanning. The volume nearest the first event began at 17:13 UTC.
4 marine hail, 3 marine thunderstorm wind. Local standard time, as filed.
There was a report of one inch hail near Redridge.
The spotter near Chassell measured 0.75 inch diameter hail at 15:10 EST.
The spotter near Chassell measured 0.75 inch diameter hail at 15:10 EST.
The observing station at Granite Island Light measured maximum wind gusts of 66 knots during the passage of severe thunderstorms.
The observing station at Granite Island Light measured maximum wind gusts of 66 knots during the passage of severe thunderstorms.
The observing station at the Big Bay Lighthouse measured thunderstorm wind gusts to near 40 knots.
The spotter near Shot Point measured 0.75 inch diameter hail.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Lake Superior in 2012Every state in 2012This day in weather history
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 379591, 379592, 379593, 395903, 395904, 395908, 379594.