Frost Dates for Chinook 35se, MT

Frost Dates

Last Spring Frost (50%) iA 50% chance that the last spring frost has already passed by this date. Most gardeners use this as their primary planting guide. May 23
First Fall Frost (50%) iA 50% chance that the first fall frost has occurred by this date. Plan to harvest or protect tender plants before this date. September 23
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

30% Probability iOnly 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 28
First Fall Frost September 18

Hard Freeze (28°F / -2°C)

Last Spring Hard Freeze May 11
First Fall Hard Freeze September 30
48.17°N, -109.01°W © OpenStreetMap

Growing Season

123 Days May 23 to September 23

USDA Hardiness Zone iHardiness 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 4b

Learn more

Temperature

10° 30° 50° 70° 90°
23°
High: 34°
Avg: 23°
Low: 12°
Jan
24°
High: 35°
Avg: 24°
Low: 13°
Feb
32°
High: 44°
Avg: 32°
Low: 20°
Mar
42°
High: 55°
Avg: 42°
Low: 29°
Apr
50°
High: 63°
Avg: 50°
Low: 37°
May
59°
High: 71°
Avg: 59°
Low: 47°
Jun
66°
High: 80°
Avg: 66°
Low: 52°
Jul
65°
High: 80°
Avg: 65°
Low: 50°
Aug
55°
High: 69°
Avg: 55°
Low: 42°
Sep
44°
High: 57°
Avg: 44°
Low: 32°
Oct
33°
High: 43°
Avg: 33°
Low: 22°
Nov
25°
High: 35°
Avg: 25°
Low: 14°
Dec
32°F
28°F
Avg High Avg Temp Avg Low Light Frost (32°F) Hard Frost (28°F)

Precipitation

0" 1" 2" 3" 4.0"
1.6"
1.55"
Jan
1.4"
1.40"
Feb
1.6"
1.64"
Mar
2.9"
2.88"
Apr
4.0"
3.96"
May
3.4"
3.43"
Jun
3.6"
3.65"
Jul
3.0"
2.97"
Aug
2.7"
2.68"
Sep
2.1"
2.07"
Oct
1.7"
1.71"
Nov
1.6"
1.55"
Dec

Sunrise / Sunset

4a7a10a1p4p7p10pNoonJanFebMarAprMayJunJulAugSepOctNovDec9h10h12h13h15h16h15h14h12h11h9h8h
Jan: 7:43 AM – 4:17 PM · 8h 34m
Feb: 7:01 AM – 4:59 PM · 9h 58m
Mar: 6:13 AM – 5:47 PM · 11h 35m
Apr: 5:17 AM – 6:43 PM · 13h 25m
May: 4:31 AM – 7:29 PM · 14h 59m
Jun: 4:05 AM – 7:55 PM · 15h 50m
Jul: 4:15 AM – 7:45 PM · 15h 29m
Aug: 4:56 AM – 7:04 PM · 14h 07m
Sep: 5:50 AM – 6:10 PM · 12h 20m
Oct: 6:44 AM – 5:16 PM · 10h 33m
Nov: 7:31 AM – 4:29 PM · 8h 57m
Dec: 7:55 AM – 4:05 PM · 8h 09m
Daylight Longest: 15h 52m · Shortest: 8h 08m

Nearby Stations

Harlem 20s, MT May 24 - September 22 Ft Belknap 2 Sw, MT May 16 - September 22 Harlem, MTMay 16 - September 21 Zortman, MTMay 18 - September 23 Chinook, MTMay 14 - September 23 Ft Assiniboine, MT May 15 - September 24

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