An upper level disturbance tracked northeast from Nebraska during the early morning hours of the 17th.As this disturbance encountered the deeper moisture plume that was established across the northern Ohio Valley region, thunderstorms initiated prior to midday, then progressed northeastward into southeast Michigan.

Hail in MIDLAND, MICHIGAN
From 17-MAY-04 14:10:00 to 17-MAY-04 14:10:00 (EST)
Location: COLEMAN
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Hail in SHIAWASSEE, MICHIGAN
From 17-MAY-04 14:25:00 to 17-MAY-04 14:25:00 (EST)
Location: OWOSSO
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in SHIAWASSEE, MICHIGAN
From 17-MAY-04 14:30:00 to 17-MAY-04 14:30:00 (EST)
Location: OWOSSO
Magnitude: 0.88 
Reported by: TRAINED SPOTTER

Hail in WAYNE, MICHIGAN
From 17-MAY-04 14:37:00 to 17-MAY-04 14:37:00 (EST)
Location: DETROIT
Magnitude: 1.00 
Reported by: FIRE DEPT/RESCUE SQUAD

Thunderstorm Wind in SAGINAW, MICHIGAN
From 17-MAY-04 15:05:00 to 17-MAY-04 15:05:00 (EST)
Location: FRANKENMUTH
Magnitude: 52 EG
Reported by: LAW ENFORCEMENT

Law enforcement reported trees and power lines down.

Thunderstorm Wind in SAGINAW, MICHIGAN
From 17-MAY-04 15:00:00 to 17-MAY-04 15:00:00 (EST)
Location: FOSTERS
Magnitude: 52 EG
Reported by: LAW ENFORCEMENT

Law enforcement reported several trees and power lines down. A large tree snapped and toppled onto a car driving along M-13.

Thunderstorm Wind in SAGINAW, MICHIGAN
From 17-MAY-04 15:05:00 to 17-MAY-04 15:05:00 (EST)
Location: BRIDGEPORT
Magnitude: 52 EG
Reported by: NEWSPAPER

Two utility poles were blown down.

Hail in LIVINGSTON, MICHIGAN
From 17-MAY-04 14:34:00 to 17-MAY-04 14:34:00 (EST)
Location: HAMBURG
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Hail in WAYNE, MICHIGAN
From 17-MAY-04 14:34:00 to 17-MAY-04 14:34:00 (EST)
Location: DETROIT
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Thunderstorm Wind in BAY, MICHIGAN
From 17-MAY-04 15:35:00 to 17-MAY-04 15:35:00 (EST)
Location: KAWKAWLIN
Magnitude: 55 EG
Reported by: FIRE DEPT/RESCUE SQUAD

Numerous trees and power lines down. Part of the roof of the Fire Department was also blown off.

Thunderstorm Wind in TUSCOLA, MICHIGAN
From 17-MAY-04 15:15:00 to 17-MAY-04 15:15:00 (EST)
Location: RICHVILLE
Magnitude: 52 EG
Reported by: NEWSPAPER

A large tree fell across M-15.

Thunderstorm Wind in TUSCOLA, MICHIGAN
From 17-MAY-04 15:15:00 to 17-MAY-04 15:15:00 (EST)
Location: REESE
Magnitude: 52 EG
Reported by: LAW ENFORCEMENT

Law enforcement reported trees and power lines down.

Thunderstorm Wind in HURON, MICHIGAN
From 17-MAY-04 16:03:00 to 17-MAY-04 16:10:00 (EST)
Location: SEBEWAING
Magnitude: 52 EG
Reported by: TRAINED SPOTTER

A trained weather spotter reported power lines blown down.

Hail in HURON, MICHIGAN
From 17-MAY-04 16:10:00 to 17-MAY-04 16:10:00 (EST)
Location: PIGEON
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Thunderstorm Wind in HURON, MICHIGAN
From 17-MAY-04 16:00:00 to 17-MAY-04 16:00:00 (EST)
Location: SEBEWAING
Magnitude: 52 EG
Reported by: TRAINED SPOTTER

A trained weather spotter reported large tree limbs down.

Hail in MIDLAND, MICHIGAN
From 17-MAY-04 14:00:00 to 17-MAY-04 14:00:00 (EST)
Location: COLEMAN
Magnitude: 1.75 
Reported by: TRAINED SPOTTER