Frost Dates for Challis, ID
Based on data from Challis AP weather station, 1 miles away
Elevation: 5253 ft
Frost Dates
Last Spring Frost (50%) A 50% chance that the last spring frost has already passed by this date. Most gardeners use this as their primary planting guide.
May 14
First Fall Frost (50%) A 50% chance that the first fall frost has occurred by this date. Plan to harvest or protect tender plants before this date.
September 25
30% Probability
Only a 30% chance of frost remaining by this date. Use these dates for a safer planting window, especially for tender plants sensitive to cold.
Last Spring Frost
May 20
First Fall Frost
September 20
Hard Freeze (28°F)
Last Spring Hard Freeze
May 1
First Fall Hard Freeze
October 7
Growing Season
134 Days
May 14 to September 25
USDA Hardiness Zone
Hardiness zones indicate which perennial plants can survive winter in your area. For annual vegetables, frost dates and growing season length matter more than hardiness zone.Zone 5b
Avg. annual minimum: −15 to −10°F
Köppen Climate
The Köppen climate classification system categorizes climates based on temperature and precipitation patterns.
BSk
Cold Semi-Arid (Steppe)
Cool to cold with low rainfall and wide temperature swings. Common in the western Great Plains and central Asia. Short growing seasons benefit from season extension techniques.
Temperature
10°
30°
50°
70°
90°
Avg High
Avg Temp
Avg Low
Light Frost (32°F)
Hard Frost (28°F)
Temperature table
| Month | Avg High | Avg Temp | Avg Low |
|---|---|---|---|
| January | 29° | 20° | 11° |
| February | 37° | 27° | 17° |
| March | 49° | 37° | 26° |
| April | 57° | 44° | 31° |
| May | 67° | 53° | 40° |
| June | 76° | 61° | 46° |
| July | 87° | 69° | 52° |
| August | 85° | 67° | 50° |
| September | 75° | 58° | 42° |
| October | 59° | 45° | 32° |
| November | 41° | 31° | 21° |
| December | 29° | 20° | 11° |
Precipitation
0"
1"
2"
2.0"
Precipitation table
| Month | Precipitation |
|---|---|
| January | 0.9 |
| February | 1.1 |
| March | 1.0 |
| April | 1.2 |
| May | 1.7 |
| June | 1.7 |
| July | 1.6 |
| August | 1.4 |
| September | 2.0 |
| October | 1.7 |
| November | 1.2 |
| December | 1.2 |
Sunrise / Sunset
Daylight
Mountain Time (MT)
Longest: 15h 22m · Shortest: 8h 38m
Sunrise and sunset table
| Month | Sunrise | Sunset | Daylight |
|---|---|---|---|
| January | 8:16 AM | 5:16 PM | 8h 60m |
| February | 7:45 AM | 5:58 PM | 10h 13m |
| March | 7:58 AM | 7:35 PM | 11h 38m |
| April | 6:60 AM | 8:15 PM | 13h 15m |
| May | 6:15 AM | 8:51 PM | 14h 36m |
| June | 5:57 AM | 9:17 PM | 15h 21m |
| July | 6:11 AM | 9:14 PM | 15h 03m |
| August | 6:45 AM | 8:37 PM | 13h 52m |
| September | 7:23 AM | 7:40 PM | 12h 17m |
| October | 8:00 AM | 6:44 PM | 10h 43m |
| November | 7:42 AM | 5:02 PM | 9h 20m |
| December | 8:13 AM | 4:52 PM | 8h 39m |
Nearby Stations
Plan Your Garden with Planter
Now that you know your frost dates, use Planter to plan your veggie garden! Planter is an easy drag-and-drop garden planner with personalized planting schedules.
Try Planter For FreeAvailable everywhere: iOS, Android, web, and more!
