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HURON COUNTY, Mich. — Residents across Huron County and Michigan’s Thumb face a heightened risk of severe thunderstorms Wednesday afternoon and evening, with forecasters warning that storms could strengthen quickly and produce damaging winds, large hail, localized flooding, and possibly an isolated tornado.
The National Weather Service office in Detroit/Pontiac placed Huron, Tuscola and Sanilac counties, along with much of southeast Michigan, under a Slight Risk for severe weather Wednesday, Sept. 2. The most recent Hazardous Weather Outlook, issued at 3:56 a.m., says conditions will become favorable for severe storms during the afternoon and evening.
The threat comes as hot, humid weather settles over the region. The Weather Service expects heat-index readings in the mid to upper 90s across Huron County and surrounding areas Wednesday afternoon.
Forecasters said isolated or more widely spaced storms could initially form before developing into clusters or lines. Storms are expected to generally move from northwest to southeast at about 35 mph.
For readers who want a quick look at changing conditions across the Thumb, Thumbwind’s Upper Thumb Webcam page offers live and near-live views from several locations around the region. The cameras can help residents see cloud cover, visibility, wind effects, and changing conditions along the Lake Huron and Saginaw Bay shoreline before heading out. The webcam page is available at https://thumbwind.com/michigan-upper-thumb-webcams/.
The National Weather Service places Huron County under a Slight Risk for severe weather today.
Storms may strengthen rapidly and generally move from northwest to southeast at about 35 mph.
Heat-index readings could reach the mid to upper 90s before storms arrive.
Damaging winds could approach 70 mph
An earlier National Weather Service outlook issued Tuesday afternoon gave a more specific indication of the potential severity Wednesday.
That forecast identified damaging winds approaching 70 mph as the primary threat, while also noting the possibility of large hail, localized flooding and an isolated tornado. The updated Wednesday morning outlook continues to classify the region at a Slight Risk and says all severe thunderstorm hazards remain possible.
The forecast does not mean every community will experience a severe storm.
Forecasters continue to stress uncertainty over exactly where storms will form and how widespread they will become. But the atmosphere is expected to support rapid storm development once thunderstorms begin.
The National Weather Service said any individual cells or clusters that develop could intensify quickly.
That makes the timing of individual storms difficult to pin down several hours in advance. Residents should monitor radar and updated warnings Wednesday rather than relying solely on the morning forecast.
Huron County could see more than one weather hazard
Damaging straight-line winds appear to be one of the main concerns. Winds near 70 mph can bring down large tree limbs, damage weaker structures, and knock out electrical service.
Large hail is another concern.
Heavy rainfall within stronger storms could also cause localized flooding, particularly on roads and in low-lying or poorly drained areas. The Weather Service specifically includes highly localized flooding among Wednesday’s potential hazards.
The tornado threat appears lower than the damaging-wind threat, but forecasters have not ruled it out. Tuesday’s outlook specifically identified an isolated tornado as possible during Wednesday’s severe-weather period.
The combination of heat and humidity will add another concern ahead of storms. Heat-index values could reach the upper 90s during the afternoon across Huron County, even though the Heat Advisory issued farther south in southeast Michigan does not include Huron County in the current outlook.
Lake Huron and Saginaw Bay boaters face added risk
The severe-weather threat extends beyond land.
The National Weather Service included Saginaw Bay, Port Austin-to-Harbor Beach and Harbor Beach-to-Port Sanilac waters in its hazardous-weather outlook Wednesday morning.
Thunderstorms over the lakes could produce wind gusts of 50 knots or greater — roughly 58 mph — along with large hail. Forecasters said storms over the water also could intensify rapidly and generally move from northwest to southeast.
Those conditions could become dangerous quickly for fishing boats, sailboats, kayaks and other small craft along Huron County’s shoreline.
Boaters planning trips on Saginaw Bay or Lake Huron Wednesday should closely monitor radar and marine warnings before leaving shore and while on the water.
Another round of storms possible later this week
Wednesday may not end the unsettled weather.
The National Weather Service says chances for strong thunderstorms will continue Thursday and Friday, with locally heavy rain possible.
For Wednesday, however, the primary concern remains the afternoon and evening period as heat and humidity combine with an approaching weather disturbance.
Residents should have a way to receive weather warnings, secure outdoor objects that could become airborne, and be prepared to move indoors if storms approach.
The Hazardous Weather Outlook is not a severe thunderstorm warning. It signals that conditions may support severe storms over the region. More specific watches and warnings may be issued as forecasters determine where storms are developing.
For Huron County, the key period to watch is Wednesday afternoon through Wednesday evening, when any developing storm could quickly become severe.
