Frost Dates for Williston, ND

Based on data from Williston Sloulin Intl AP weather station, 2 miles away

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 21
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 26
First Fall Frost September 17

Hard Freeze (28°F)

Last Spring Hard Freeze May 11
First Fall Hard Freeze September 28
48.15°N, -103.62°W © OpenStreetMap

Growing Season

123 Days May 21 to September 21

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

Avg. annual minimum: −30 to −25°F (−34 to −32°C)

Learn more

Köppen Climate iThe Köppen climate classification system categorizes climates based on temperature and precipitation patterns.

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°
12°
High: 22°F
Avg: 12°F
Low: 1°F
Jan
16°
High: 27°F
Avg: 16°F
Low: 6°F
Feb
29°
High: 40°F
Avg: 29°F
Low: 18°F
Mar
42°
High: 56°F
Avg: 42°F
Low: 29°F
Apr
54°
High: 67°F
Avg: 54°F
Low: 40°F
May
63°
High: 77°F
Avg: 63°F
Low: 50°F
Jun
70°
High: 85°F
Avg: 70°F
Low: 56°F
Jul
69°
High: 84°F
Avg: 69°F
Low: 54°F
Aug
58°
High: 73°F
Avg: 58°F
Low: 44°F
Sep
43°
High: 56°F
Avg: 43°F
Low: 30°F
Oct
28°
High: 38°F
Avg: 28°F
Low: 17°F
Nov
16°
High: 26°F
Avg: 16°F
Low: 6°F
Dec
32°F
28°F
Avg High Avg Temp Avg Low Light Frost (32°F) Hard Frost (28°F)

Precipitation

0" 1" 2" 3" 3.3"
1.2"
1.18"
Jan
0.9"
0.95"
Feb
1.5"
1.51"
Mar
1.6"
1.56"
Apr
3.0"
3.03"
May
3.2"
3.20"
Jun
3.3"
3.30"
Jul
2.6"
2.64"
Aug
2.2"
2.21"
Sep
1.6"
1.63"
Oct
1.2"
1.20"
Nov
1.2"
1.24"
Dec

Sunrise / Sunset

4a7a10a1p4p7p10pNoonJanFebMarAprMayJunJulAugSepOctNovDec8.5h10h11.5h13.5h15h16h15.5h14h12.5h10.5h9h8h
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

Williston Exp Farm, ND May 13 - September 26 Watford City, ND May 9 - September 27 Tioga 1e, NDMay 11 - September 26 Keene 3s, NDMay 20 - September 20 Sidney, MTMay 11 - September 27 Wildrose 3nw, ND May 18 - September 20

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