Frost Dates for Ft Assiniboine, MT

Elevation: 815 m

Frost Dates

Last Spring Frost (50%) May 15

First Fall Frost (50%) September 24

30% Probability

Last Spring Frost May 20

First Fall Frost September 18

Hard Freeze (28°F)

Last Spring Hard Freeze May 4

First Fall Hard Freeze October 2

48.50°N, 109.80°W © OpenStreetMap

Growing Season

132 Days May 15 to September 24

USDA Hardiness Zone

Zone 4a

Avg. annual minimum: −30 to −25°F

Learn more

Köppen Climate

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.

Köppen climate map

Temperature

0° 30° 60° 90°

18°

Jan

22°

Feb

32°

Mar

44°

Apr

54°

May

62°

Jun

70°

Jul

68°

Aug

58°

Sep

44°

Oct

31°

Nov

21°

Dec

32°F

28°F

Avg High Avg Temp Avg Low Light Frost (32°F) Hard Frost (28°F)

Temperature table

Average monthly temperatures (°F)
Month	Avg High	Avg Temp	Avg Low
January	28°	18°	7°
February	33°	22°	10°
March	44°	32°	19°
April	57°	44°	31°
May	67°	54°	40°
June	75°	62°	49°
July	85°	70°	54°
August	84°	68°	52°
September	73°	58°	43°
October	58°	44°	31°
November	42°	31°	20°
December	32°	21°	11°

Precipitation

0" 1" 2" 3"

1.2"

Jan

1.3"

Feb

1.9"

Mar

2.1"

Apr

2.9"

May

3.0"

Jun

2.9"

Jul

2.3"

Aug

2.6"

Sep

1.8"

Oct

1.4"

Nov

1.2"

Dec

Precipitation table

Average monthly precipitation (inches)
Month	Precipitation
January	1.2
February	1.3
March	1.9
April	2.1
May	2.9
June	3.0
July	2.9
August	2.3
September	2.6
October	1.8
November	1.4
December	1.2

Sunrise / Sunset

Jan: 7:44 AM – 4:16 PM · 8h 31m

Feb: 7:02 AM – 4:58 PM · 9h 56m

Mar: 6:13 AM – 5:47 PM · 11h 34m

Apr: 5:17 AM – 6:43 PM · 13h 26m

May: 4:30 AM – 7:30 PM · 15h 01m

Jun: 4:03 AM – 7:57 PM · 15h 53m

Jul: 4:14 AM – 7:46 PM · 15h 32m

Aug: 4:56 AM – 7:04 PM · 14h 09m

Sep: 5:50 AM – 6:10 PM · 12h 20m

Oct: 6:44 AM – 5:16 PM · 10h 32m

Nov: 7:32 AM – 4:28 PM · 8h 55m

Dec: 7:57 AM – 4:03 PM · 8h 07m

Daylight Longest: 15h 55m · Shortest: 8h 05m

Sunrise and sunset table

Sunrise, sunset, and daylight on the 15th of each month (local solar time)
Month	Sunrise	Sunset	Daylight
January	7:44 AM	4:16 PM	8h 31m
February	7:02 AM	4:58 PM	9h 56m
March	6:13 AM	5:47 PM	11h 34m
April	5:17 AM	6:43 PM	13h 26m
May	4:30 AM	7:30 PM	15h 01m
June	4:03 AM	7:57 PM	15h 53m
July	4:14 AM	7:46 PM	15h 32m
August	4:56 AM	7:04 PM	14h 09m
September	5:50 AM	6:10 PM	12h 20m
October	6:44 AM	5:16 PM	10h 32m
November	7:32 AM	4:28 PM	8h 55m
December	7:57 AM	4:03 PM	8h 07m

Nearby Stations

Havre City Co AP, MT May 15 - September 23 Gildford, MTMay 24 - September 15 Chinook, MTMay 14 - September 23 Big Sandy, MT May 17 - September 25 Simpson 6 N - Wildhorse, MT May 26 - September 15 Rudyard 19s, MT May 23 - September 19

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