First Snow: When Winter's Opening Flake Lands, State by State

The snow line takes about four months to cross the country. The Rockies and interior Alaska typically record measurable snow in late September and early October, the northern Plains and Upper Midwest in late October, the Northeast and Great Lakes through November, the mid South in December and January, and the Gulf South barely at all. Every state page tracks its own window against today.

The first MEASURABLE snowfall: at least 0.1 inch accumulating in a day at the reference station, which is the National Weather Service convention. The first flakes in the air (a trace) usually fly one to three weeks earlier but never enter the record books, which is why your memory of first snow and the official date rarely agree.

Interior and northern Alaska, where Fairbanks has a median first measurable snow in the first days of October. In the lower 48 it is the high Rockies and adjacent High Plains: Casper and Cheyenne in Wyoming both carry early-October medians, and Denver is close behind mid-October.

Yes, and those three states get a different kind of page here. No station in them records measurable snow even half of all winters, so instead of publishing a fake median, their pages document the real events: Miami's 1977 flurries, the historic January 2025 Gulf Coast snowstorm, and Hawaii's summit snows above 13,000 feet.

It is a planning anchor, not a forecast: by the median date, half of past winters had already seen measurable snow and half had not. Any single winter commonly runs two to three weeks either side of it. Once you are inside your state's window, the 10 day forecast beats climatology every time.

NOAA daily station records. NOAA's official 1991-2020 climate normals include seasonal snowfall totals but no first-snow date statistics, so we derive the dates ourselves from GHCN-Daily observations: the first 0.1 inch day of each July-June season, taken across the 30 normals-period seasons, reported as 10th, 50th, and 90th percentile dates, with gappy seasons excluded and NOAA-flagged values skipped. The full method is on every state page.