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When does it first snow in Chicago (O'Hare Airport), IL?

At Chicago (O'Hare Airport), the typical date of the first measurable snowfall (0.1 inch or more in a day) is Nov 20. That is the median over the last 30 snow seasons: half of seasons saw it earlier, half later. In about 1 season in 10 it came by Oct 31, and in 1 in 10 not until Dec 12 or later. The earliest was Oct 12 (2006-07) and the latest Dec 28 (2021-22). A first snowfall of at least 1 inch in a single day typically arrives around Dec 4, and 100% of seasons had one. The first freeze of fall (a low of 32°F or colder) typically comes around Oct 26, and the last freeze of spring around Apr 21.

This season so far (2026-27, data through Oct 16, 2026): no measurable snow recorded yet; no 32°F freeze recorded yet at this station. Compare with the typical dates above. This is observed data and can lag by a day or two, and it is not a forecast.

Nov 20Median first measurable snow (0.1"+)

Dec 4Median first 1"+ snowfall

38.3"Average snowfall per season

39%Chance of white Christmas (1"+ on ground Dec 25)

Oct 26Median first fall freeze (≤32°F)

Apr 21Median last spring freeze (≤32°F)

184Median freeze-free days between

First snowfall dates at Chicago (O'Hare Airport)

First day with…	Median date	Typical range (10th–90th pct)	Earliest in 30 seasons	Latest in 30 seasons	Seasons with one
0.1" of snow or more (measurable)	Nov 20	Oct 31 – Dec 12	Oct 12 (2006-07)	Dec 28 (2021-22)	100%
1" of snow or more	Dec 4	Nov 15 – Jan 2	Oct 30 (2019-20)	Jan 25 (2012-13)	100%
3" of snow or more	Dec 21	Nov 24 – Jan 25	Oct 31 (2019-20)	Feb 26 (2012-13)	96%

Based on 27 seasons (July–June, 1995-96 to 2024-25) with at least 85% complete daily snowfall records at the station. Dates are for a single day’s snowfall, so "1 inch" means one calendar day with 1" or more, not total accumulation.

Chance the first snow has already happened by a given date

Snowfall	By Nov 1	By Dec 1	By Jan 1
0.1"+ (measurable)	15%	67%	100%
1"+	4%	37%	85%

In spring, the last measurable snowfall of the season typically falls around Apr 5 (median).

White Christmas odds in Chicago (O'Hare Airport)

NOAA defines a white Christmas as at least 1 inch of snow on the ground on the morning of December 25. Using the last 30 years of daily snow-depth records (1995–2024) at this station, Chicago (O'Hare Airport) had that in 39% of years, at least 3 inches in 11%, and at least 6 inches in 7%. The average depth on Dec 25 was 1.2 inches and the deepest was 12 inches. New snow was falling (0.1" or more) on Christmas Day itself in 30% of years. Based on 28 years with a recorded depth on Dec 25.

Chance of at least 1 inch of snow on the ground, by date

Share of the last 30 years with 1"+ snow depth within 3 days of each date. Snow cover is most likely around Jan 28 (59%). Red line: Dec 25.

First and last freeze dates in Chicago (O'Hare Airport)

Threshold	Event	Median date	Typical range (10th–90th pct)	Earliest / latest	Years with one
32°F or colder (freeze)	First in fall	Oct 26	Oct 6 – Nov 10	Sep 22 (1995) / Nov 20 (2024)	100%
32°F or colder (freeze)	Last in spring	Apr 21	Apr 9 – May 1	–	100%
28°F or colder (hard freeze)	First in fall	Nov 9	Oct 27 – Nov 20	Oct 11 (1996) / Dec 1 (2020)	100%
28°F or colder (hard freeze)	Last in spring	Apr 5	Mar 24 – Apr 18	–	100%

Based on the station’s daily minimum temperature, 1995–2024. “Freeze” here means a daily low at or below the threshold, which is not the same as visible frost. Your yard can differ by several degrees and days from an airport weather station, so use these as planning odds, not guarantees.

The median stretch between the last spring freeze and the first fall freeze (the freeze-free season) was about 184 days.

Nearby weather stations

Source station: Chicago Ohare Intl Ap (USW00094846), elevation 672 ft. Data: NOAA NCEI GHCN-Daily. Computed by First Snow Dates; how we calculate this. Historical averages only; for a forecast see weather.gov.

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