Frost Dates for Blackleaf, 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. June 9
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 3
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 June 17
First Fall Frost August 29

Hard Freeze (28°F / -2°C)

Last Spring Hard Freeze May 23
First Fall Hard Freeze September 17
48.01°N, -112.44°W © OpenStreetMap

Growing Season

86 Days June 9 to September 3

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 5a

Learn more

Temperature

0° 20° 40° 60° 80°
23°
High: 37°
Avg: 23°
Low: 9°
Jan
24°
High: 38°
Avg: 24°
Low: 10°
Feb
31°
High: 44°
Avg: 31°
Low: 17°
Mar
40°
High: 53°
Avg: 40°
Low: 27°
Apr
48°
High: 63°
Avg: 48°
Low: 33°
May
55°
High: 69°
Avg: 55°
Low: 41°
Jun
63°
High: 80°
Avg: 63°
Low: 46°
Jul
62°
High: 80°
Avg: 62°
Low: 44°
Aug
54°
High: 70°
Avg: 54°
Low: 37°
Sep
42°
High: 56°
Avg: 42°
Low: 27°
Oct
31°
High: 44°
Avg: 31°
Low: 18°
Nov
24°
High: 37°
Avg: 24°
Low: 11°
Dec
32°F
28°F
Avg High Avg Temp Avg Low Light Frost (32°F) Hard Frost (28°F)

Precipitation

0" 1" 2" 3" 3.6"
1.2"
1.24"
Jan
1.3"
1.26"
Feb
1.8"
1.81"
Mar
2.4"
2.35"
Apr
3.5"
3.49"
May
3.6"
3.56"
Jun
2.7"
2.66"
Jul
2.5"
2.49"
Aug
2.5"
2.51"
Sep
1.8"
1.79"
Oct
1.4"
1.43"
Nov
1.2"
1.24"
Dec

Sunrise / Sunset

4a7a10a1p4p7p10pNoonJanFebMarAprMayJunJulAugSepOctNovDec9h10h12h13h15h16h15h14h12h11h9h8h
Jan: 7:43 AM – 4:17 PM · 8h 35m
Feb: 7:01 AM – 4:59 PM · 9h 58m
Mar: 6:13 AM – 5:47 PM · 11h 35m
Apr: 5:18 AM – 6:42 PM · 13h 25m
May: 4:31 AM – 7:29 PM · 14h 58m
Jun: 4:06 AM – 7:54 PM · 15h 49m
Jul: 4:16 AM – 7:44 PM · 15h 28m
Aug: 4:57 AM – 7:03 PM · 14h 07m
Sep: 5:50 AM – 6:10 PM · 12h 20m
Oct: 6:43 AM – 5:17 PM · 10h 33m
Nov: 7:31 AM – 4:29 PM · 8h 58m
Dec: 7:55 AM – 4:05 PM · 8h 11m
Daylight Longest: 15h 51m · Shortest: 8h 10m

Nearby Stations

Bynum 4 Sse, MT May 16 - September 27 Choteau, MTMay 28 - September 12 Choteau 8ne, MT May 20 - September 22 Valier, MTMay 17 - September 24 Conrad, MTMay 20 - September 19 Gibson Dam, MT June 12 - September 8

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