Lore Check: It Always Snows in Denver Before Halloween

"Bring a real coat Saturday, it always snows in Denver before Halloween." You hear it every October, usually right when somebody's planning a costume that involves very little fabric.

We pulled daily snowfall for Denver's official weather site from NOAA's ACIS database and checked each of the last 30 seasons, 1996-2025, for at least 0.1 inch (measurable, the National Weather Service standard) on any day from Jul 1 through Oct 30 (NOAA ACIS, checked Oct 21). Then we lined that up against the full record back to 1882 and NWS Boulder's own first-snow tables.

The ruling: Overblown

Overblown. 18 of the last 30 seasons (1996-2025, 60%) had measurable snow before Oct 31 (NOAA ACIS, checked Oct 21). Better than a coin flip, and a long way from always.

The misses have piled up lately. 2021, 2022 and 2024 had no measurable snow before Halloween. Neither did 2025. Earlier misses were 1998, 2003 and 2004, then 2008 and 2010, then 2014 through 2016. The first measurable snow didn't show until Dec 10 in 2021 and Nov 29 in 2025, the two latest first snows since 1882 (NWS Boulder, checked Oct 21).

The saying had a stronger case over the long haul: 99 of 133 seasons (74%) from 1882 to 2025 cleared the bar (NOAA ACIS, checked Oct 21). NWS Boulder posts Oct 19 as the average first measurable snow since 1882, and the 1996-2025 median is Oct 23. Through Oct 20, 2026, there was no measurable snow this season. Anything after Oct 20 wasn't in our data yet.

The receipts

• NWS NOWData: the ACIS daily snowfall record for the official Denver site, where 18 of 30 seasons (1996-2025) had measurable snow before Oct 31, checked Oct 21.
• NWS Boulder: Denver Fall/Winter Statistics: average first measurable snow of Oct 19 since 1882, with 12-10 (2021) and 11-29 (2025) topping the latest-first-snow table, checked Oct 21.
• Unofficial Networks (news): as of Oct 20, 2026, Denver had no snow yet, and meteorologist Chris Bianchi put the odds of measurable snow in the next 7-10 days at 10% or lower, checked Oct 21.

What to actually do

Build Saturday's costume around the Oct 31 normal at the official site, a high of 59F and a low of 31F (NOAA ACIS, 1991-2020 normals, checked Oct 21), so bring a jacket for the walk home after dark and leave the snow boots in the closet. Only 1 of the last 30 Halloweens (2002) had measurable snow on the day itself, so check the NWS Boulder forecast Friday before you commit.

How we checked

We pulled daily snowfall from NOAA ACIS for the official Denver site, filling ACIS's mid-1995 to mid-2007 gap with the Central Park station, the official site then. We counted seasons from 1996 through 2025 with 0.1 inch or more on any day from Jul 1 to Oct 30. Our rule: 90% or more is Legit, 70-89% Mostly Legit, 40-69% Overblown, under 40% Pure Lore, so 60% is Overblown. One official site stands in for the whole city, and the foothills and west side often see snow first.