Several rounds of thunderstorm squalls brought strong winds to much of the open lake and nearshore waters. A squall moved across southern Lake Michigan during the early morning hours producing wind gusts up to 52 kts and very intense lightning from St Joseph to Holland. Other thunderstorm squalls also crossed the lake during the mid afternoon and evening hours.  They brought wind gusts of 35 to 40 kts from St Joseph to Holland and adjacent open lake waters.

Marine Thunderstorm Wind in SOUTH HAVEN TO HOLLAND MI, LAKE MICHIGAN
From 19-JUN-09 20:25:00 to 19-JUN-09 20:35:00 (EST-5)
Location: SOUTH HAVEN HARBOR
Magnitude: 45.00 MG
Reported by: C-MAN Station

Wind gusts up to 45 kts occurred at the South Haven GLERL site (SVNM4) in association with a cluster of thunderstorms that moved onshore.

Marine Thunderstorm Wind in GRAND HAVEN TO WHITEHALL MI, LAKE MICHIGAN
From 19-JUN-09 03:00:00 to 19-JUN-09 03:35:00 (EST-5)
Location: MUSKEGON HARBOR
Magnitude: 35.00 MG
Reported by: C-MAN Station

Wind gusted to 35 kts for thirty-five minutes at the GLERL observing station in Muskegon (MKGM4).  The winds were associated with a wake low and a convective complex that moved across Lake Michigan an onshore near South Haven.

Marine Thunderstorm Wind in SOUTH HAVEN TO HOLLAND MI, LAKE MICHIGAN
From 19-JUN-09 12:55:00 to 19-JUN-09 13:00:00 (EST-5)
Location: SOUTH HAVEN HARBOR
Magnitude: 45.00 MG
Reported by: C-MAN Station

A 45 kt gust was measured at South Haven GLERL sight (SVNM4) as a squall line moved onshore.  There was no evidence of strong wind gusts associated with the line in the open waters of Lake Michigan.

Marine Thunderstorm Wind in SOUTH HAVEN TO HOLLAND MI, LAKE MICHIGAN
From 19-JUN-09 19:15:00 to 19-JUN-09 19:45:00 (EST-5)
Location: HOLLAND HARBOR
Magnitude: 55.00 EG
Reported by: NWS Storm Survey

Estimated wind gusts of 55 kts occurred as a severe thunderstorm moved onshore.  Gusts were estimated from a NWS survey of tree damage along the coast in the coast in around the harbor, and analysis of amateur video taken at Holland State Park during the storm.

Marine Thunderstorm Wind in ST JOSEPH TO SOUTH HAVEN MI, LAKE MICHIGAN
From 19-JUN-09 20:15:00 to 19-JUN-09 20:30:00 (EST-5)
Location: ST. JOSEPH HARBOR
Magnitude: 45.00 MG
Reported by: C-MAN Station

Wind gusts up to 45 kts occurred at the St. Joseph GLERL site (SJOM4) in association with a cluster of thunderstorms that moved onshore.

Marine Thunderstorm Wind in ST JOSEPH TO SOUTH HAVEN MI, LAKE MICHIGAN
From 19-JUN-09 02:00:00 to 19-JUN-09 03:15:00 (EST-5)
Location: SOUTH HAVEN HARBOR
Magnitude: 52.00 MG
Reported by: Official NWS Observations

A 60 mph measured wind gust was recorded at the South Haven coastal observation site. Severe thunderstorms with wind gusts between 50 and 60 mph and continuous lightning impacted Lake Michigan waters from St. Joseph north to South Haven and Holland.

Marine Thunderstorm Wind in SOUTH HAVEN TO HOLLAND MI, LAKE MICHIGAN
From 19-JUN-09 02:00:00 to 19-JUN-09 03:15:00 (EST-5)
Location: SOUTH HAVEN HARBOR
Magnitude: 52.00 MG
Reported by: Official NWS Observations

A 60 mph measured wind gust was recorded at the South Haven coastal observation site.  Severe thunderstorms with wind gusts to 60 mph and continuous lightning impacted Lake Michigan waters from South Haven to Holland.

Marine Thunderstorm Wind in HOLLAND TO GRAND HAVEN MI, LAKE MICHIGAN
From 19-JUN-09 19:15:00 to 19-JUN-09 19:45:00 (EST-5)
Location: HOLLAND HARBOR
Magnitude: 55.00 EG
Reported by: NWS Storm Survey

Estimated wind gusts of 55 kts occurred as a severe thunderstorm moved onshore.  Gusts were estimated from a NWS survey of tree damage along the coast in the coast in around the harbor, and analysis of amateur video taken at Holland State Park during the storm.