Name: Waterspout in Lake Michigan, August 21, 2018
Start: 2018-08-21T04:02
End: 2018-08-21T05:45
Location: Lake Michigan

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 MKX wrote it up.

A supercell thunderstorm likely produced a series of waterspouts over Lake Michigan, about 10 miles east of Milwaukee Harbor during the early morning. The waterspouts were strongly indicated by Doppler Radar and several of the waterspouts were photographed.

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 Milwaukee, WI wrote its last area forecast discussion before the first event at Aug 21, 12:53 AM CST, 3 hours 9 minutes earlier.

Area forecast discussion, Aug 21, 12:53 AM CST, 3 hours 9 minutes before

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Hazardous weather outlook, Aug 21, 3:36 AM CST, 26 minutes before

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In the hours before

Local storm report, Aug 20, 10:11 PM CST, 5 hours 51 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1111 PM CDT MON AUG 20 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1015 PM     FLASH FLOOD      2 SSW MIDDLETON         43.08N 89.53W
08/20/2018                   DANE               WI   BROADCAST MEDIA

            RELAYED REPORT OF 30 PEOPLE FROM A HEALTH
            CLINIC BEING EVACUATED, REQUESTING A WATER
            RESCUE AND BUS.

&&

DDV

Local storm report, Aug 20, 10:22 PM CST, 5 hours 40 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1122 PM CDT MON AUG 20 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1100 PM     HEAVY RAIN       2 S MIDDLETON           43.07N 89.51W
08/20/2018  M10.23 INCH      DANE               WI   COCORAHS

&&

DDV

Local storm report, Aug 20, 11:04 PM CST, 4 hours 58 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
1204 AM CDT TUE AUG 21 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1034 PM     HEAVY RAIN       3 W MIDDLETON           43.10N 89.56W
08/20/2018  M11.05 INCH      DANE               WI   PUBLIC

&&

DDV

The radar

The Milwaukee radar (KMKX), 66 km away, was scanning. The volume nearest the first event began at 09:59 UTC.

Open the radar archive at this moment

Event by event

1 waterspout. Local standard time, as filed.

Waterspout, Port Washington to North Point Light Wi 5nm Offshore to Mid Lake

When: August 21, 4:02 AM CST to 5:45 AM CST
Where: Port Washington to North Point Light Wi 5nm Offshore to Mid Lake forecast zone, 10 mi NE of North Point Lthouse to 16 mi SE of North Point Lthouse
Reported by: Public
Coordinates: 43.182, -87.790

A member of the International Centre for Waterspout Research took several photographs of waterspouts southeast of Milwaukee Harbor. Doppler radar indicates a likely series of waterspouts occurred over the open waters of Lake Michigan between roughly 5 am CDT to 645 am CDT Tuesday, August 21st.

What these are

Waterspout: A tornado over water. One that moves ashore is filed as a tornado from the coastline on.

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

The same day elsewhere

More

Every storm in Lake Michigan in 2018 Every state in 2018 This 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 2026-09-30. Each event’s entry at NCEI: 767512.