Frost Dates for Ahtanum, WA

Based on data from Yakima #2 weather station, 3 miles away

Elevation: 1247 ft

Frost Dates

Last Spring Frost (50%) A 50% chance that the last spring frost has already passed by this date. Most gardeners use this as their primary planting guide. April 8
First Fall Frost (50%) A 50% chance that the first fall frost has occurred by this date. Plan to harvest or protect tender plants before this date. October 23

30% Probability

Only 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 April 18
First Fall Frost October 17

Hard Freeze (28°F)

Last Spring Hard Freeze March 16
First Fall Hard Freeze November 3
46.56°N, 120.62°W © OpenStreetMap

Growing Season

198 Days April 8 to October 23

USDA Hardiness Zone

Hardiness 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 7a

Avg. annual minimum: 0 to 5°F

Learn more

Köppen Climate

The 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

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
January40°33°27°
February48°39°30°
March57°46°34°
April65°53°40°
May74°61°48°
June80°67°54°
July88°74°60°
August88°73°59°
September79°65°51°
October64°52°40°
November49°40°32°
December38°32°26°

Precipitation

Precipitation table
Average monthly precipitation (inches)
MonthPrecipitation
January2.2
February1.8
March1.9
April1.4
May1.4
June1.3
July0.0
August0.0
September0.6
October1.4
November1.6
December2.2

Sunrise / Sunset

Daylight Pacific Time (PT) Longest: 15h 38m · Shortest: 8h 22m
Sunrise and sunset table
Sunrise, sunset, and daylight on the 15th of each month (Pacific Time (PT))
Month Sunrise Sunset Daylight
January7:49 AM4:34 PM8h 46m
February7:15 AM5:19 PM10h 04m
March7:24 AM6:60 PM11h 36m
April6:22 AM7:43 PM13h 21m
May5:34 AM8:23 PM14h 49m
June5:14 AM8:51 PM15h 37m
July5:29 AM8:46 PM15h 17m
August6:06 AM8:07 PM14h 00m
September6:47 AM7:06 PM12h 19m
October7:29 AM6:06 PM10h 38m
November7:14 AM4:21 PM9h 08m
December7:47 AM4:10 PM8h 23m

Nearby Stations

Yakima Air Terminal, WA May 8 - October 4 Selah 2 Ne, WAMay 5 - October 4 Wapato, WAApril 21 - October 15 Moxee City 10 E, WA May 4 - October 10 Ellensburg, WAMay 8 - October 2 Sunnyside #2, WA April 30 - October 8

Plan Your Garden with Planter

Now that you know your frost dates, use Planter to plan your veggie garden! Planter is an easy drag-and-drop garden planner with personalized planting schedules.

Try Planter For Free

Available everywhere: iOS, Android, web, and more!

Planter app garden planner preview