🌷 Last Frost Dates for Hermiston, Oregon 97838

The last 36°F Spring frost date is 30% likely to be on May 9. (See detailed probabilities below.)

The last 32°F light freeze date is 30% likely to be on Apr 27. (See detailed probabilities below.)

(See also 🍂 First Fall Frost Dates.)

Last frost date probabilities for Hermiston, OR are based on historical climate data.

Always check your local forecast for the most up-to-date frost warnings.

What is a Last Frost Date?

The last spring frost signals when your area is safe from freezing temperatures. Tender plants can now grow outdoors without cold damage! This marks the beginning of the growing season. Last spring frost serves as your essential starting point for planting warm-season crops. It's also time to remove winter protection from your perennials. Enjoy the longer days and warmer weather!

How to use the Last Frost Date?

Start seeds indoors several weeks before your last frost date. This gives plants time to reach transplanting size when weather permits. Plan your outdoor planting schedule around your area's average last frost date. Plant some crops before and some after this date to protect against weather changes. Look for spots in your yard where frost stays longer or disappears earlier. Create your own frost map to use all available growing space and extend your season. Keep watching your local weather forecast to catch any surprise late frosts.

Last Frost Date Probabilities

Probability of frost (36°F) on or after…
10% chanceMay 18
20% chanceMay 13
30% chanceMay 9
40% chanceMay 6
50% chanceMay 3
60% chanceMay 1
70% chanceApr 29
80% chanceApr 25
90% chanceApr 20
Probability of light freeze (32°F) on or after…
10% chanceMay 4
20% chanceApr 30
30% chanceApr 27
40% chanceApr 23
50% chanceApr 20
60% chanceApr 16
70% chanceApr 12
80% chanceApr 7
90% chanceApr 1
Probability of moderate freeze (28°F) on or after…
10% chanceApr 21
20% chanceApr 14
30% chanceApr 9
40% chanceApr 5
50% chanceApr 1
60% chanceMar 29
70% chanceMar 26
80% chanceMar 20
90% chanceMar 12
Probability of moderate hard freeze (24°F) on or after…
10% chanceApr 4
20% chanceMar 28
30% chanceMar 22
40% chanceMar 16
50% chanceMar 11
60% chanceMar 7
70% chanceMar 2
80% chanceFeb 25
90% chanceFeb 16
Probability of hard freeze (20°F) on or after…
10% chanceMar 12
20% chanceMar 5
30% chanceMar 1
40% chanceFeb 26
50% chanceFeb 20
60% chanceFeb 15
70% chanceFeb 9
80% chanceFeb 1
90% chanceJan 17
Probability of severe hard freeze (16°F) on or after…
10% chanceMar 2
20% chanceFeb 25
30% chanceFeb 18
40% chanceFeb 11
50% chanceFeb 5
60% chanceJan 31
70% chanceJan 21
80% chanceJan 11
90% chanceDec 31

Agricultural climatic data from weather station: HERMISTON 2 NW (USC00353818)