Thunderstorms developed across Northern Lower Michigan in unseasonably warm and humid air ahead of a strong cold front that was moving across the Great Lakes Region. Thunderstorms developed during the late afternoon and lasted through the evening. Most of these storms produced very heavy rain and hail. The heavy rainfall also produced some street flooding in the cities of Manistee and Cadillac. A few of these storms produced severe wind gusts.  An isolated tornado was reported across the Gladwin-Arenac County line; however,  the hail and flooding had the greatest impact.

Hail in ALCONA, MICHIGAN
From 12-MAY-00 18:12:00 to 12-MAY-00 18:12:00 (EST)
Location: HARRISVILLE
Magnitude: 1.00 
Reported by: AMATEUR RADIO

Hail in ALCONA, MICHIGAN
From 12-MAY-00 18:13:00 to 12-MAY-00 18:13:00 (EST)
Location: HARRISVILLE
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in LEELANAU, MICHIGAN
From 12-MAY-00 17:15:00 to 12-MAY-00 17:15:00 (EST)
Location: MAPLE CITY
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in CHARLEVOIX, MICHIGAN
From 12-MAY-00 17:27:00 to 12-MAY-00 17:27:00 (EST)
Location: IRONTON
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in ALCONA, MICHIGAN
From 12-MAY-00 18:10:00 to 12-MAY-00 18:10:00 (EST)
Location: HARRISVILLE
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Flash Flood in MANISTEE, MICHIGAN
From 12-MAY-00 15:15:00 to 12-MAY-00 16:00:00 (EST)
Location: MANISTEE
Reported by: LAW ENFORCEMENT

Up to six inches of water covered city streets.

Flash Flood in WEXFORD, MICHIGAN
From 12-MAY-00 14:45:00 to 12-MAY-00 15:45:00 (EST)
Location: CADILLAC
Reported by: LAW ENFORCEMENT

Up to six inches of water covered some city streets.

Thunderstorm Wind in ALCONA, MICHIGAN
From 12-MAY-00 18:10:00 to 12-MAY-00 18:10:00 (EST)
Location: COUNTYWIDE
Magnitude: 50 E
Reported by: LAW ENFORCEMENT

Trees and power lines were blown down over portions of the entire county.

Thunderstorm Wind in ROSCOMMON, MICHIGAN
From 12-MAY-00 16:30:00 to 12-MAY-00 16:30:00 (EST)
Location: HOUGHTON LAKE
Magnitude: 50 E
Reported by: LAW ENFORCEMENT

Several trees were blown down.

Tornado in ARENAC, MICHIGAN
From 12-MAY-00 15:38:00 to 12-MAY-00 15:40:00 (EST)
Location: ALGER
Tornado F-scale: F0
Reported by: TRAINED SPOTTER

A tornado briefly touched down in far northeast Gladwin County and crossed into Arenac County lifting near interstate 75.

Hail in OGEMAW, MICHIGAN
From 12-MAY-00 15:45:00 to 12-MAY-00 15:45:00 (EST)
Location: PRESCOTT
Magnitude: 1.75 
Reported by: FIRE DEPT/RESCUE SQUAD

Hail in IOSCO, MICHIGAN
From 12-MAY-00 15:45:00 to 12-MAY-00 15:45:00 (EST)
Location: WHITTEMORE
Magnitude: 1.75 
Reported by: TRAINED SPOTTER

Hail in OGEMAW, MICHIGAN
From 12-MAY-00 15:48:00 to 12-MAY-00 15:48:00 (EST)
Location: PRESCOTT
Magnitude: 1.75 
Reported by: FIRE DEPT/RESCUE SQUAD

Hail in IOSCO, MICHIGAN
From 12-MAY-00 16:03:00 to 12-MAY-00 16:03:00 (EST)
Location: WHITTEMORE
Magnitude: 0.88 
Reported by: TRAINED SPOTTER

Hail in IOSCO, MICHIGAN
From 12-MAY-00 16:08:00 to 12-MAY-00 16:08:00 (EST)
Location: EAST TAWAS
Magnitude: 0.88 
Reported by: AMATEUR RADIO

Tornado in GLADWIN, MICHIGAN
From 12-MAY-00 15:36:00 to 12-MAY-00 15:38:00 (EST)
Location: GLADWIN
Tornado F-scale: F0
Reported by: TRAINED SPOTTER

A tornado briefly touched down in far northeast Gladwin County and crossed into Arenac County lifting near interstate 75.

Hail in OGEMAW, MICHIGAN
From 12-MAY-00 15:12:00 to 12-MAY-00 15:12:00 (EST)
Location: WEST BRANCH ARPT
Magnitude: 0.88 
Reported by: TRAINED SPOTTER

Hail in MISSAUKEE, MICHIGAN
From 12-MAY-00 16:20:00 to 12-MAY-00 16:20:00 (EST)
Location: LAKE CITY
Magnitude: 0.75 
Reported by: EMERGENCY MANAGER

Hail in LEELANAU, MICHIGAN
From 12-MAY-00 17:02:00 to 12-MAY-00 17:02:00 (EST)
Location: LELAND
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in LEELANAU, MICHIGAN
From 12-MAY-00 17:09:00 to 12-MAY-00 17:09:00 (EST)
Location: SUTTONS BAY
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in OGEMAW, MICHIGAN
From 12-MAY-00 15:50:00 to 12-MAY-00 15:50:00 (EST)
Location: PRESCOTT
Magnitude: 1.00 
Reported by: AMATEUR RADIO

Hail in IOSCO, MICHIGAN
From 12-MAY-00 15:50:00 to 12-MAY-00 15:50:00 (EST)
Location: WHITTEMORE
Magnitude: 1.00 
Reported by: AMATEUR RADIO

Thunderstorm Wind in MANISTEE, MICHIGAN
From 12-MAY-00 13:23:00 to 12-MAY-00 13:23:00 (EST)
Location: MANISTEE
Magnitude: 75 E
Reported by: TRAINED SPOTTER

Hail in WEXFORD, MICHIGAN
From 12-MAY-00 14:05:00 to 12-MAY-00 14:05:00 (EST)
Location: CADILLAC
Magnitude: 0.75 
Reported by: AMATEUR RADIO