Frost dates · Idaho
When is the first frost in Boise?
Boise right now
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- Tomorrow62°F / 43°FClouds
- Monday47°F / 41°FRain
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Live from OpenWeatherMap. Alerts from the National Weather Service.
In a typical year, Boise’s first frost comes around October 21 and its last around April 24.
One year in ten the first frost comes as early as October 5, and nine years in ten it has arrived by November 5. One year in ten the last frost is over as early as April 4, and nine years in ten it is over by May 9. Boise averages about 108 nights a year at 32°F or colder, with about 179 frost-free days in between in a typical year. It’s frost season here, and the last frost usually comes around April 24. That makes it the 43rd earliest first frost of the 117 cities we track where it freezes most years.
Last updated
No freeze in the forecast for the next 48 hours.
Boise’s last frost comes in late April, which is when the foothills finally commit to being green.
Live 48-hour check from OpenWeatherMap, refreshed about every half hour. Alerts from the National Weather Service.
Frost dates, early, typical and late years
| Early year (1 in 10) | Typical | Late year (1 in 10) | |
|---|---|---|---|
| First frost | October 5 | October 21 | November 5 |
| Last frost | April 4 | April 24 | May 9 |
A frost date here is a night when the official thermometer reads 32°F or colder. Frost on the ground can show up on clear, calm nights a few degrees milder.
Cities with about the same first frost
- Fort Wayne, Indiana: first frost around October 21
- Omaha, Nebraska: first frost around October 21
- Des Moines, Iowa: first frost around October 20
Source: NOAA U.S. Climate Normals, 1991 to 2020, station USW00024131.