When does it first snow in Boise, ID?
First snowfall dates at Boise
| 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 4 – Dec 8 | Oct 10 (2008-09) | Jan 1 (2024-25) | 100% |
| 1" of snow or more | Dec 2 | Nov 12 – Jan 8 | Oct 10 (2008-09) | Apr 6 (2002-03) | 97% |
| 3" of snow or more | Dec 22 | Dec 2 – Jan 24 | Nov 13 (2014-15) | Feb 12 (2020-21) | 57% |
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) | 7% | 67% | 97% |
| 1"+ | 3% | 40% | 77% |
In spring, the last measurable snowfall of the season typically falls around Mar 22 (median).
White Christmas odds in Boise
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, Boise had that in 33% of years, at least 3 inches in 20%, and at least 6 inches in 3%. The average depth on Dec 25 was 1.1 inches and the deepest was 9 inches. New snow was falling (0.1" or more) on Christmas Day itself in 23% of years. Based on 30 years with a recorded depth on Dec 25.
Share of the last 30 years with 1"+ snow depth within 3 days of each date. Snow cover is most likely around Dec 25 (30%). Red line: Dec 25.
First and last freeze dates in Boise
| 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 5 – Nov 8 | Sep 28 (1999) / Nov 16 (2016) | 100% |
| 32°F or colder (freeze) | Last in spring | May 1 | Apr 14 – May 13 | – | 100% |
| 28°F or colder (hard freeze) | First in fall | Nov 2 | Oct 17 – Nov 14 | Oct 10 (2019) / Nov 20 (2015) | 100% |
| 28°F or colder (hard freeze) | Last in spring | Apr 6 | Mar 15 – Apr 23 | – | 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 174 days.
Nearby weather stations
Source station: Boise Air Terminal (USW00024131), elevation 2,823 ft. Data: NOAA NCEI GHCN-Daily. Computed by First Snow Dates; how we calculate this. Historical averages only; for a forecast see weather.gov.
Planning for winter? Heat pump vs gas furnace, propane and oil: heating cost in Idaho (on our sister site PlugVsPump, from EIA prices).