Spokane, WA Frost Dates: Last Spring and First Fall Frost

Spokane gardeners can count on April 26 as the even-odds date for the last spring frost and October 15 as the even-odds date for the first fall frost, which adds up to 170 days without a freeze in a typical year.

Put May 10 and September 30 on the calendar as well. A spring freeze after the first of them, or a fall freeze before the second, happens in only one year out of ten, so those dates cover nine years in ten. Against the 100-city median of 229 days, Spokane has 59 days less room before frost returns.

The numbers belong to Spokane Felts Field, NOAA station USW00094176, which sits 5.3 miles east of the Census Bureau's internal point for Spokane at an elevation of about 1,950 feet.

Spokane's last spring frost, by chance

Frost is still possible on April 10 in nine springs out of ten and on April 26 in five; only one spring in ten sees a freeze as late as May 10.

Only 30 days separate the earliest and latest of these dates, a tighter run than most of the 100 cities here, so the typical date is a fairly dependable guide in Spokane.

When is the first frost in Spokane?

In Spokane the first freeze has arrived by September 30 in one fall out of ten, by October 15 in five, and by October 31 in nine.

From the earliest first freeze to the latest is 31 days, close to the middle of the pack.

How long is the frost-free season in Spokane?

The season is somewhat shorter than the middle of these pages, so a seed packet's days to maturity deserve a second look. Seasons here barely vary: the typical year gives 170 days and a short one still gives 149 days, only 21 days less, a steadier record than most cities on these pages.

The season lengths come from NOAA's simulated years, not from subtracting one typical date from the other, so the two will not match to the day. At Spokane Felts Field a night at or below 32°F turns up in 100% of years, which means these dates apply every winter.

When a hard freeze reaches Spokane

Hard freezes are late to arrive in Spokane and early to leave: October 27 in fall, 12 days behind the first frost, and April 4 in spring, 22 days ahead of the last. One spring in ten still has a 28°F night on or after April 26, and one fall in ten sees the first by October 11.

Using Spokane's frost dates in the garden

University of New Hampshire Extension sorts vegetables by how they cope with cold. Cool-season crops go out before the last frost: counting from April 26, cabbage transplants go in on March 29 and lettuce from March 29 to April 5. Tender crops wait until it has passed, with peppers going out on May 10 and beans sown on or after April 26. Peas are the exception to the count: University of New Hampshire Extension says to plant them as soon as the soil thaws, whatever the frost date.

Counting from the late date, May 10, instead of the typical one delays every after-frost crop by 14 days. That is the price of a one-in-ten spring that most years will not need.

Of the 34 crops in the fall planner, 23 still have a July-or-later last planting day in Spokane once NC State Extension's days to harvest and University of Georgia Extension's harvest allowance of 18 days are counted back from frost. The other 11 do not. The slowest crop that still fits is collard greens, which needs 90 days before the early first frost and so must be in by July 2.

Worked example: tomatoes in Spokane

Suppose you want tomatoes in Spokane. University of New Hampshire Extension says to set transplants out one to two weeks after the last frost. Counting from the typical date, April 26, the window runs from May 3 to May 10. Counting from the late date, May 10, it moves to May 17 through May 24, which is 14 days later.

Indoors, tomato seeds go in six to eight weeks ahead of set-out; from the first day of the late window that is March 22 to April 5.

Between the last set-out day and the early first frost on September 30 lie 129 days. Tomatoes need 75 to 85 days by NC State Extension's count, so the schedule has 44 days of slack even in an early-frost year.

About the Spokane Felts Field station

5.3 miles east of the city's internal point, the station is close but not on top of Spokane.

Its elevation is about 1,950 feet. Of the 100 stations behind these pages, 14 sit higher and 85 lower. NOAA flags this station's record as representative, the code R, for the data behind its 50% last-frost value.

Because the Census file has no elevation for Spokane, we cannot say how far your yard is above or below this station. When yours is clearly higher or lower, open the nearby stations in the frost dates tool and favor the colder one.

Nearby cities and their frost dates

The closest city to Spokane on these pages, Seattle, WA, is 229 miles away, a long way, so the three below are a look at other climates more than at neighbors. Note that the Seattle station stands 1,890 feet lower than Spokane's.

• Seattle, WA, 229 miles to the west: last frost March 8, first frost November 23, 259 days frost-free; its last frost comes 49 days before Spokane's, and it has 89 days more without frost.
• Tacoma, WA lies 237 miles west of Spokane. Typical last frost March 8, first frost November 14, 250 days between; the last frost is 49 days earlier than in Spokane, and the season runs 80 days longer.
• Boise, ID, 287 miles to the south: last frost April 24, first frost October 21, 179 days frost-free; its last frost is nearly the same as Spokane's, and the frost-free season is 9 days longer than Spokane's.

Take these dates further

Open the frost dates tool with this station already chosen to see the whole ladder of probability dates, or try the nearby stations in the same list. The spring planting planner and the fall planting planner turn the same dates into a full crop list, and the hardiness zone lookup tells you which perennials will survive the winter.

Every city covered is on the city frost dates index, sorted by state.

Where these numbers come from

The frost and freeze dates are NOAA's U.S. Climate Normals for 1991–2020 (doi:10.25921/4ek7-fk11), copied from the station's own record without adjustment; NOAA's documentation defines each probability. The Census Bureau's 2024 Gazetteer places Spokane on the map, and its Vintage 2024 estimates, 230,609 people here, decide which cities get a page.

Planting dates here are those rules from University of New Hampshire Extension, NC State Extension and University of Georgia Extension, applied to this station's frost dates and nothing else. The methodology page explains how each figure is checked.

These dates describe odds over many years, not next week's weather. Look at the forecast before you plant, and keep a sheet or row cover ready for a night that does not follow the odds.