The National Weather Service had 131 active alerts posted Saturday tied to wildfire smoke and fire weather, down sharply from Friday’s 234, even as the footprint held nearly steady across 18 states and the District of Columbia, including Colorado, Idaho, Illinois, Indiana, Massachusetts, Maine, Michigan, Minnesota, Montana, New Jersey, New York, Ohio, Oregon, Pennsylvania, Vermont, Washington, Wisconsin and West Virginia.
The drop in raw alert count masks a shift in where the danger is concentrated. Where Friday’s story centered on ground-level air quality warnings in the Mid-Atlantic, Saturday’s alerts are clustering over the Great Lakes, where the Weather Service has paired Dense Smoke Advisories with Small Craft Advisories along dozens of marine zones spanning Lake Michigan and Lake Superior. Forecasters describe dense smoke cutting visibility to 1 nautical mile across zones from Port Washington to North Point Light, Wisconsin, and Sheboygan to Port Washington, Wisconsin, combined with waves of 4 to 6 feet that make small-craft travel hazardous. The Dense Smoke Advisories are set to run from 3 p.m. Saturday afternoon until 7 a.m. CDT Monday in several of those zones, with the Small Craft Advisories following behind starting around 7 p.m. Saturday evening.
That marine emphasis is new: Friday’s alerts were dominated by inland air-quality warnings, including Maryland’s Code Red particulate alert. Saturday’s data shows the smoke has pushed north and west into Great Lakes shipping lanes stretching from Michigan City, Indiana, to the Upper Peninsula, with zones affected around Munising, Marquette, Grand Marais and the Keweenaw Peninsula in Michigan, plus Green Bay and the Wisconsin shoreline.
Meanwhile, the underlying fire-weather threat driving the Red Flag Warnings persists in the West, with Colorado, Idaho, Montana, Oregon and Washington still carrying active warnings for conditions favorable to rapid fire spread. The Weather Service continues to base those warnings on the standard combination of low relative humidity and sustained wind, though specific wind-speed and humidity thresholds for Saturday’s warnings were not detailed in the available advisories.
The narrowing of overall alert volume — nearly 43% fewer than Friday — suggests some easing of the ground-level smoke crisis that prompted health warnings across the Mid-Atlantic earlier in the week. But the shift toward marine advisories on the Great Lakes signals the smoke plume itself hasn’t dissipated so much as moved, now threatening boaters and shipping traffic rather than commuters. Residents in the affected Great Lakes states should expect reduced visibility on the water into Monday morning, while residents in Western fire-weather states should continue to avoid outdoor burning and monitor local Red Flag Warning timing, which the Weather Service updates as conditions change.