Frost Dates for Rogers Pass 9 Nne, 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 21
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 15
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 29
First Fall Frost September 8

Hard Freeze (28°F / -2°C)

Last Spring Hard Freeze May 7
First Fall Hard Freeze September 28
47.19°N, -112.29°W © OpenStreetMap

Growing Season

117 Days May 21 to September 15

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 4a

Learn more

Temperature

10° 30° 50° 70° 90°
27°
High: 36°
Avg: 27°
Low: 17°
Jan
27°
High: 37°
Avg: 27°
Low: 16°
Feb
34°
High: 45°
Avg: 34°
Low: 23°
Mar
42°
High: 53°
Avg: 42°
Low: 30°
Apr
50°
High: 62°
Avg: 50°
Low: 38°
May
58°
High: 71°
Avg: 58°
Low: 46°
Jun
66°
High: 82°
Avg: 66°
Low: 51°
Jul
65°
High: 81°
Avg: 65°
Low: 49°
Aug
55°
High: 70°
Avg: 55°
Low: 41°
Sep
44°
High: 55°
Avg: 44°
Low: 32°
Oct
33°
High: 42°
Avg: 33°
Low: 25°
Nov
26°
High: 34°
Avg: 26°
Low: 18°
Dec
32°F
28°F
Avg High Avg Temp Avg Low Light Frost (32°F) Hard Frost (28°F)

Precipitation

0" 2" 4" 5.0"
1.6"
1.55"
Jan
1.6"
1.58"
Feb
1.9"
1.92"
Mar
3.0"
3.04"
Apr
4.8"
4.83"
May
4.7"
4.73"
Jun
3.3"
3.25"
Jul
3.9"
3.85"
Aug
5.0"
4.95"
Sep
4.0"
4.01"
Oct
2.2"
2.21"
Nov
1.7"
1.66"
Dec

Sunrise / Sunset

4a7a10a1p4p7p10pNoonJanFebMarAprMayJunJulAugSepOctNovDec9h10h12h13h15h16h15h14h12h11h9h8h
Jan: 7:39 AM – 4:21 PM · 8h 41m
Feb: 6:59 AM – 5:01 PM · 10h 02m
Mar: 6:12 AM – 5:48 PM · 11h 36m
Apr: 5:19 AM – 6:41 PM · 13h 22m
May: 4:34 AM – 7:26 PM · 14h 52m
Jun: 4:09 AM – 7:51 PM · 15h 42m
Jul: 4:19 AM – 7:41 PM · 15h 22m
Aug: 4:59 AM – 7:01 PM · 14h 03m
Sep: 5:50 AM – 6:10 PM · 12h 19m
Oct: 6:42 AM – 5:18 PM · 10h 36m
Nov: 7:28 AM – 4:32 PM · 9h 04m
Dec: 7:51 AM – 4:09 PM · 8h 18m
Daylight Longest: 15h 43m · Shortest: 8h 17m

Nearby Stations

Holter Dam, MT May 19 - September 24 Augusta, MTMay 19 - September 21 Lincoln Rs, MT Cascade 5 S, MT May 21 - September 19 Adel, MTJune 4 - September 12 Sun Rvr 4 S, MT June 2 - September 10

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