Frost Dates for Altona, Canada

Based on data from Gretna (Aut) weather station, 5 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 20
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 23
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 25
First Fall Frost September 18

Hard Freeze (−2°C)

Last Spring Hard Freeze May 8
First Fall Hard Freeze October 4
49.10°N, -97.56°W © OpenStreetMap

Growing Season

126 Days May 20 to September 23

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.

Dfb Warm-Summer Continental

Warm summers and cold, snowy winters. A shorter growing season than hot-summer continental. Hardy vegetables, root crops, and cool-season greens do well. Season extension is valuable.

Köppen climate map

Temperature

-20° -5° 10° 25°
-15°
High: -10°C
Avg: -15°C
Low: -20°C
Jan
-13°
High: -8°C
Avg: -13°C
Low: -18°C
Feb
-6°
High: -1°C
Avg: -6°C
Low: -10°C
Mar
4°
High: 10°C
Avg: 4°C
Low: -2°C
Apr
11°
High: 18°C
Avg: 11°C
Low: 5°C
May
17°
High: 23°C
Avg: 17°C
Low: 11°C
Jun
20°
High: 26°C
Avg: 20°C
Low: 13°C
Jul
19°
High: 26°C
Avg: 19°C
Low: 12°C
Aug
14°
High: 20°C
Avg: 14°C
Low: 7°C
Sep
6°
High: 11°C
Avg: 6°C
Low: 0°C
Oct
-3°
High: 1°C
Avg: -3°C
Low: -8°C
Nov
-12°
High: -7°C
Avg: -12°C
Low: -16°C
Dec
0°C
−2°C
Avg High Avg Temp Avg Low Light Frost (0°C) Hard Frost (−2°C)

Precipitation

0 mm 30 mm 60 mm 90 mm
3 mm
2.5 mm
Jan
3 mm
2.5 mm
Feb
8 mm
7.6 mm
Mar
10 mm
10.2 mm
Apr
66 mm
66.0 mm
May
89 mm
88.9 mm
Jun
66 mm
66.0 mm
Jul
58 mm
58.4 mm
Aug
53 mm
53.3 mm
Sep
25 mm
25.4 mm
Oct
13 mm
12.7 mm
Nov
0 mm
0.0 mm
Dec

Sunrise / Sunset

4a7a10a1p4p7p10pNoonJanFebMarAprMayJunJulAugSepOctNovDec8.5h10h11.5h13.5h15h16h15.5h14h12.5h10.5h9h8h
Jan: 7:47 AM – 4:13 PM · 8h 27m
Feb: 7:03 AM – 4:57 PM · 9h 54m
Mar: 6:13 AM – 5:47 PM · 11h 34m
Apr: 5:16 AM – 6:44 PM · 13h 28m
May: 4:28 AM – 7:32 PM · 15h 05m
Jun: 4:01 AM – 7:59 PM · 15h 58m
Jul: 4:12 AM – 7:48 PM · 15h 36m
Aug: 4:54 AM – 7:06 PM · 14h 11m
Sep: 5:50 AM – 6:10 PM · 12h 20m
Oct: 6:45 AM – 5:15 PM · 10h 30m
Nov: 7:34 AM – 4:26 PM · 8h 51m
Dec: 7:59 AM – 4:01 PM · 8h 02m
Daylight Longest: 15h 60m · Shortest: 8h 00m

Nearby Stations

Cavalier 7nw, ND May 12 - September 30 Pembina, NDMay 16 - September 29 Morden Cda Cs, Canada May 15 - September 30 Hallock, MNMay 8 - September 30 Carman, Canada May 18 - September 20 Carman U Of M Cs, Canada May 20 - September 23

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