Lake Michigan, 2020

Marine Thunderstorm Wind in Lake Michigan, August 2, 2020

August 2, 2020 · NWS LOT · 1 event in 1 county or zone

Scattered thunderstorms moved across portions of southern Lake Michigan during the afternoon of August 2nd.

Where it happened

Every event with a place to put it. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
1

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.

What happened

The episode as NWS LOT wrote it up.

Scattered thunderstorms moved across portions of southern Lake Michigan during the afternoon of August 2nd.

What forecasters said that day

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 Chicago, IL wrote its last area forecast discussion before the first event at Aug 2, 2:31 PM CST, 2 hours 41 minutes earlier.

Area forecast discussion, Aug 2, 2:31 PM CST, 2 hours 41 minutes before
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Hazardous weather outlook, Aug 2, 2:51 PM CST, 2 hours 21 minutes before
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In the hours before

Special weather statement, Aug 2, 1:13 PM CST, 3 hours 59 minutes before
Special Weather Statement
National Weather Service Chicago/Romeoville
213 PM CDT Sun Aug 2 2020

ILZ008-010-022000-
Ogle IL-Lee IL-
213 PM CDT Sun Aug 2 2020

...SIGNIFICANT WEATHER ADVISORY FOR LEE AND SOUTHWESTERN OGLE
COUNTIES UNTIL 300 PM CDT...

At 211 PM CDT, Doppler radar was tracking a strong thunderstorm 4
miles southwest of Polo, or 5 miles west of Dixon, moving east at 25
mph. Other storms were developing across western Lee and Ogle
Counties as well.

Penny size hail and wind gusts up to 50 mph will be possible with
the storm near Dixon, and may be realized with other storms in this
area through 300 PM as well.

Locations impacted include...
Dixon, Amboy, Polo, Franklin Grove, Ashton, Lost Nation, Sublette,
Woodhaven Lakes, Grand Detour, Nelson, Harmon, Woodland Shores,
Eldena, Woosung, Lee Center, Chana and Nachusa.

This includes...  Castle Rock State Park, Lee County Fairgrounds,
Sauk Valley College, and White Pines State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4201 8969 4199 8917 4158 8917 4158 8963
      4193 8963 4193 8969
TIME...MOT...LOC 1911Z 283DEG 20KT 4190 8962

FRIEDLEIN
Special weather statement, Aug 2, 3:38 PM CST, 1 hour 34 minutes before
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Special weather statement, Aug 2, 4:14 PM CST, 58 minutes before
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Local storm report, Aug 2, 5:12 PM CST, 0 minutes before
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The radar

The Chicago radar (KLOT), 99 km away, was scanning. The volume nearest the first event began at 23:11 UTC.

Open the radar archive at this moment

Event by event

1 marine thunderstorm wind. Local standard time, as filed.

Marine Thunderstorm Wind, Burns Harbor to Michigan City in

When
August 2, 5:12 PM CST to 5:14 PM CST
Where
Burns Harbor to Michigan City in forecast zone, Michigan City
Measured
35 kt (40 mph) measured gust
Reported by
C-MAN Station
Coordinates
41.730, -86.910

What these are

Marine Thunderstorm Wind
Thunderstorm winds of 34 knots or more over coastal or lake waters.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Lake Michigan in 2020Every state in 2020This day in weather history

Sources

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: 908908.