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When does it first snow in Williamsport, PA?

At Williamsport, the typical date of the first measurable snowfall (0.1 inch or more in a day) is Nov 22. 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 Nov 7, and in 1 in 10 not until Dec 16 or later. The earliest was Oct 15 (2009-10) and the latest Jan 12 (2015-16). 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 22, and the last freeze of spring around Apr 28.

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 22Median first measurable snow (0.1"+)

Dec 4Median first 1"+ snowfall

33.6"Average snowfall per season

28%Chance of white Christmas (1"+ on ground Dec 25)

Oct 22Median first fall freeze (≤32°F)

Apr 28Median last spring freeze (≤32°F)

177Median freeze-free days between

First snowfall dates at Williamsport

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 22	Nov 7 – Dec 16	Oct 15 (2009-10)	Jan 12 (2015-16)	100%
1" of snow or more	Dec 4	Nov 14 – Jan 7	Oct 29 (2011-12)	Feb 9 (2015-16)	100%
3" of snow or more	Dec 22	Nov 23 – Jan 18	Nov 14 (1995-96)	Feb 13 (2006-07)	90%

Based on 30 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)	10%	70%	93%
1"+	7%	43%	80%

In spring, the last measurable snowfall of the season typically falls around Mar 24 (median).

White Christmas odds in Williamsport

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, Williamsport had that in 28% of years, at least 3 inches in 16%, and at least 6 inches in 4%. The average depth on Dec 25 was 0.9 inches and the deepest was 8 inches. New snow was falling (0.1" or more) on Christmas Day itself in 17% of years. Based on 25 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 21 (59%). Red line: Dec 25.

First and last freeze dates in Williamsport

Threshold	Event	Median date	Typical range (10th–90th pct)	Earliest / latest	Years with one
32°F or colder (freeze)	First in fall	Oct 22	Oct 8 – Nov 3	Oct 3 (2003) / Nov 7 (2014)	100%
32°F or colder (freeze)	Last in spring	Apr 28	Apr 14 – May 14	–	100%
28°F or colder (hard freeze)	First in fall	Nov 7	Oct 20 – Nov 14	Oct 9 (2001) / Nov 23 (2015)	100%
28°F or colder (hard freeze)	Last in spring	Apr 7	Mar 27 – Apr 19	–	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 177 days.

Nearby weather stations

Source station: Williamsport Rgnl Ap (USW00014778), elevation 524 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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