Frost dates / Washington / Richland

Frost dates in Richland, WA

The station on this page is RICHLAND, WA US (USC00457015), 2.3 miles from the city point. Population in the Census 2024 estimate is 64,372.

Zone 7bUSDA average annual extreme minimum 5°F to 10°F, from ZIP 99352 (2.9 miles from the city point used on this page).

Median last 32°F is April 6. Median first 32°F is October 24. The 50% growing-season length is 200 days. The green band runs from the median last frost to the median first frost. Thin ticks mark the 10%, 50%, and 90% dates.

Outside the median season Growing seasonTicks: 10%, 50%, and 90%

Last 32°F in spring

NCEI’s probability is the chance the last spring minimum of 32°F or lower occurs on or after the date.

Probability	Date	How to read it
90%	March 22	Earlier date. A last 32°F on or after this day is common.
50%	April 6	Median.
10%	April 24	Later date. A last 32°F on or after this day is uncommon.

First 32°F in fall

NCEI’s probability is the chance the first autumn minimum of 32°F or lower occurs on or before the date.

Probability	Date	How to read it
10%	October 10	Earlier date. A first 32°F on or before this day is uncommon.
50%	October 24	Median.
90%	November 8	Later date. A first 32°F on or before this day is common.

32°F growing-season length

Days between the last spring 32°F and the first autumn 32°F. The figure is a length the season meets or exceeds at that probability, from NCEI, not a subtraction done on this site.

Probability the season is at least this long	Days
10%	221
50%	200
90%	179

28°F threshold

	10%	50%	90%
Last, on or after	April 5	March 18	March 1
First, on or before	October 20	November 4	November 23
Season at least	255 days	229 days	205 days

36°F threshold

	10%	50%	90%
Last, on or after	May 8	April 25	April 11
First, on or before	September 30	October 14	October 27
Season at least	192 days	171 days	153 days

Station RICHLAND, WA US (USC00457015). Completeness flag S, 30 years used for the 32°F dates. NCEI’s annual probability of at least one day at or below 32°F is 100%. Freeze dates are conditional on that threshold occurring. Elevation 113.7 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Check a crop against this station

Richland, WA

Zone 7bAverage annual extreme minimum 5°F to 10°F

Outside the median season Growing seasonTicks: 10%, 50%, and 90%

Washington. Nearest qualified station: RICHLAND, WA US (USC00457015), 2.3 miles. Median last 32°F April 6. Median first 32°F October 24. The 50% growing-season length is 200 days.

Open the ZIP page

32°F probabilities at this station

	10%	50%	90%
Last 32°F on or after	April 24	April 6	March 22
First 32°F on or before	October 10	October 24	November 8

Column order matches the NCEI file: for the last freeze, 10% is the later date and 90% is the earlier date. How to read the probabilities.

A wall calendar surrounded by vegetables, herbs, seed packets, and watering cans.

Planting calendar

Frost dates for Washington are above. Planting windows appear for states with a cited extension guide. The fall and seed tools use the numbers you enter and the station dates.

Date checks use your device’s calendar and appear after the page loads.