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Frost Dates in Oklahoma
First and last frost dates across Oklahoma, computed from 47 NOAA weather stations (1991–2020 climate normals). Your exact date depends on your city and microclimate — use the ZIP lookup on the main tool for a station-specific answer.
Last spring frost
Apr 6
statewide median · range Mar 27–Apr 26
First fall frost
Oct 31
statewide median · range Oct 17–Nov 8
Growing season
208 days
median · range 173–227
Stations used
47
NOAA 1991–2020 normals
Frost dates by city
Median dates from the nearest NOAA station to each city. The "cautious" date is the 10% spring value — planting after it means only a ~10% chance of a later frost.
| City | Nearest station | Last spring frost | First fall frost | Growing season | Safe transplant |
|---|---|---|---|---|---|
| Oklahoma City | Oklahoma Cy Will Rogers World · 7 mi | Apr 4 (cautious: Apr 20) | Nov 2 | 213 days | Apr 18 |
| Tulsa | Tulsa Intl Ap · 7 mi | Mar 31 (cautious: Apr 15) | Nov 4 | 220 days | Apr 14 |
| Norman | Norman 3Sse · 3 mi | Apr 3 (cautious: Apr 18) | Nov 3 | 212 days | Apr 17 |
How frost varies across Oklahoma
Spring frost timing spans about 30 days across the state. Madill in southeastern Oklahoma typically sees its last spring frost around March 27, while Boise City in northwestern Oklahoma doesn't clear frost until about April 26. Within any city, low spots and valleys run colder than the station average; areas near buildings and pavement run warmer.
When to plant in Oklahoma
As a rule of thumb, cool-season crops (lettuce, peas, spinach) can go in 2–4 weeks before your last spring frost; warm-season transplants (tomatoes, peppers) should wait about 2 weeks after it — around April 20 for the statewide median. Check your city's row above rather than the statewide median: a 30-day statewide spread makes the city-level date the one that matters.
These are climate normals (what's typical), not forecasts. For the current year, watch the 10-day forecast around your planting date.
How this is computed
Statewide medians are the median of the 47 NOAA stations' median frost dates — half the stations run earlier, half later. City rows use the nearest station with 30-year freeze records. Dates are 32°F freeze probabilities from NOAA NCEI 1991–2020 U.S. Climate Normals; nothing is estimated or interpolated.
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Frequently asked questions
When is the last frost date in Oklahoma?
The statewide median last spring frost is April 6, but it ranges from March 27 to April 26 depending on where in the state you are. Use your city's row in the table above, or the ZIP lookup on the main tool, for a station-specific date.
When can I plant tomatoes outside in Oklahoma?
Warm-season transplants like tomatoes should wait about two weeks after your last spring frost — around April 20 for the statewide median. Your city may differ by weeks; check the "safe transplant" column in the city table.
How long is the growing season in Oklahoma?
The median growing season across 47 NOAA stations is 208 days, ranging from 173 to 227 days by location.
Why do frost dates vary so much within Oklahoma?
Frost timing follows latitude, elevation, and local terrain. Across Oklahoma, last spring frost dates span about 30 days — from around March 27 near Madill to April 26 near Boise City. Microclimates (low spots, valleys, urban heat) shift dates further at the garden level.
Where does this data come from?
All frost dates are computed from the NOAA National Centers for Environmental Information 1991–2020 U.S. Climate Normals freeze data (public domain), using each station's 32°F freeze probability statistics. No dates are estimated or interpolated.