No active National Weather Service alerts for Ontonagon County right now. This page is the live destination for Ontonagon County (county seat: Ontonagon) — bookmark it to check active watches, warnings, and advisories from NWS Marquette, plus regional context, common weather hazards, and the most recent alerts.
Michigan's Upper Peninsula sits between Lake Superior to the north and Lakes Michigan and Huron to the south. Counties in this region see some of the most extreme winter weather in the continental U.S., with annual lake-effect snowfall regularly exceeding 200 inches in the Keweenaw Peninsula and prolonged sub-zero cold snaps in January and February. The growing season is short and the population is sparse — most counties have fewer than 25,000 residents. Severe summer thunderstorms occur but tornadoes are rare.
Ontonagon County is served by NWS Marquette, headquartered in Negaunee Township, MI, which issues all official severe-weather watches, warnings, and advisories for the county under the SAME geographic code MIC131. Alerts shown above come directly from the National Weather Service public-alerts feed and update within seconds of issuance.
Live data covering Ontonagon County right now — refreshes every few minutes.
Ontonagon County's gross domestic product reached $169M in 2024 (current dollars), per the U.S. Bureau of Economic Analysis. That places the county #82 among Michigan's 83 counties for total economic output. Output grew2.2% year-over-year vs. 2023.
Source: U.S. Bureau of Economic Analysis — Regional Economic Accounts (CAGDP1). Current-dollar GDP, all industries.
Live EPA water-quality data for Ontonagon County is temporarily unavailable. For current public water-system reports, visit the EPA ECHO Drinking Water Search and the Michigan EGLE Drinking Water program.
Based on Ontonagon County's upper peninsula geography, residents and visitors should be prepared for these recurring weather threats:
A Tornado Warning means a tornado has been sighted or indicated by radar in Ontonagon County or an adjacent area — take shelter immediately. Move to the lowest floor of a sturdy building, away from windows, and into an interior room (basement, bathroom, or closet). Mobile homes and vehicles are not safe; if you're in either, leave for a sturdy structure if you can do so safely. Tornado Warnings are typically issued for 30–60 minutes; stay sheltered until the warning expires or NWS Marquette confirms the threat has passed. Ontonagon County residents should monitor a NOAA Weather Radio (programmed for SAME code MIC131), local TV, or this page.
A Flood Warning means flooding is occurring or imminent in Ontonagon County. Do not drive through flooded roads — most flood-related deaths in Michigan occur in vehicles attempting to cross water. If you live in a low-lying area near Ontonagon or along major waterways in the county, monitor official water-level reports from the U.S. Geological Survey and prepare to move to higher ground. Flash Flood Warnings carry the same urgency on a shorter time horizon — typically less than an hour to act.
Winter Storm Warnings in Ontonagon County indicate hazardous winter weather (heavy snow, freezing rain, sleet, or blizzard conditions) is occurring or imminent. Avoid travel; if you must drive, carry an emergency kit (blankets, food, water, flashlight, charged phone). Lake-effect snow can produce 1–3 inches per hour in narrow bands — conditions can change drastically over short distances. Heating-source safety is critical: never run generators or grills indoors, and check carbon-monoxide detectors before relying on alternative heat sources.
Weather rarely respects county lines — check active alerts in Ontonagon County's neighbors:
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