Frost Dates for Sun Prairie, MT

Based on data from Great Falls Intl AP weather station, 6 miles away

Elevation: 3340 ft

Frost Dates

Last Spring Frost (50%) May 19

First Fall Frost (50%) September 24

30% Probability

Last Spring Frost May 25

First Fall Frost September 19

Hard Freeze (28°F)

Last Spring Hard Freeze May 5

First Fall Hard Freeze October 3

47.54°N, 111.48°W © OpenStreetMap

Growing Season

128 Days May 19 to September 24

USDA Hardiness Zone

Zone 4b

Avg. annual minimum: −25 to −20°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

10° 30° 50° 70° 90°

25°

Jan

26°

Feb

34°

Mar

42°

Apr

52°

May

59°

Jun

68°

Jul

67°

Aug

57°

Sep

45°

Oct

34°

Nov

26°

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	35°	25°	15°
February	37°	26°	15°
March	46°	34°	22°
April	55°	42°	30°
May	65°	52°	38°
June	73°	59°	46°
July	84°	68°	51°
August	83°	67°	50°
September	72°	57°	43°
October	57°	45°	33°
November	44°	34°	24°
December	36°	26°	16°

Precipitation

0" 1" 2" 3" 3.4"

1.4"

Jan

1.2"

Feb

1.6"

Mar

2.3"

Apr

3.4"

May

3.2"

Jun

2.2"

Jul

2.4"

Aug

2.5"

Sep

2.0"

Oct

1.5"

Nov

1.3"

Dec

Precipitation table

Average monthly precipitation (inches)
Month	Precipitation
January	1.4
February	1.2
March	1.6
April	2.3
May	3.4
June	3.2
July	2.2
August	2.4
September	2.5
October	2.0
November	1.5
December	1.3

Sunrise / Sunset

Jan: 8:15 AM – 4:54 PM · 8h 39m

Feb: 7:40 AM – 5:40 PM · 10h 01m

Mar: 7:47 AM – 7:23 PM · 11h 35m

Apr: 6:44 AM – 8:07 PM · 13h 23m

May: 5:55 AM – 8:49 PM · 14h 54m

Jun: 5:34 AM – 9:18 PM · 15h 44m

Jul: 5:49 AM – 9:13 PM · 15h 24m

Aug: 6:28 AM – 8:32 PM · 14h 04m

Sep: 7:10 AM – 7:30 PM · 12h 19m

Oct: 7:53 AM – 6:28 PM · 10h 35m

Nov: 7:40 AM – 4:42 PM · 9h 02m

Dec: 8:14 AM – 4:29 PM · 8h 16m

Daylight Mountain Time (MT) Longest: 15h 46m · Shortest: 8h 14m

Sunrise and sunset table

Sunrise, sunset, and daylight on the 15th of each month (Mountain Time (MT))
Month	Sunrise	Sunset	Daylight
January	8:15 AM	4:54 PM	8h 39m
February	7:40 AM	5:40 PM	10h 01m
March	7:47 AM	7:23 PM	11h 35m
April	6:44 AM	8:07 PM	13h 23m
May	5:55 AM	8:49 PM	14h 54m
June	5:34 AM	9:18 PM	15h 44m
July	5:49 AM	9:13 PM	15h 24m
August	6:28 AM	8:32 PM	14h 04m
September	7:10 AM	7:30 PM	12h 19m
October	7:53 AM	6:28 PM	10h 35m
November	7:40 AM	4:42 PM	9h 02m
December	8:14 AM	4:29 PM	8h 16m

Nearby Stations

Great Falls Wfo, MT May 12 - September 28 Great Falls 16st, MT May 6 - October 1 Sun Rvr 4 S, MT June 2 - September 10 Carter 14 W, MT May 23 - September 23 Cascade 5 S, MT May 21 - September 19 Fairfield, MT May 13 - September 27

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