What USDA zone is Fort Smith, AR?

The zone on this page is 8a, from ZIP 72903 in the 2023 PRISM table of the USDA Plant Hardiness Zone Map. That ZIP is 0.7 miles from the city point. USDA defines the zone as the average annual extreme minimum, shown here as 10°F to 15°F. It is a winter-cold band, not a frost date and not a forecast.

How far away is the weather station?

The station named on this page is 1.2 miles from the city point in a straight line. Frost dates are 1991–2020 NOAA climate normals for that instrument. They are not a National Weather Service forecast for one night, and they are not the temperature in every yard. The page names the station so the miles stay attached to the dates.

Frost dates in Fort Smith, AR

Direct answer. In Fort Smith, AR, the nearest qualified NOAA station is FT SMITH RGNL AP, AR US (USW00013964), 1.2 miles from the city point. The median last 32°F date is March 25, and the median first 32°F date is November 6, from the 1991–2020 U.S. Climate Normals. The 2023 USDA zone is 8a (10°F to 15°F), from ZIP 72903 in the PRISM table, 0.7 miles from the same city point.

Population in the Census 2024 estimate is 90,507. The station is FT SMITH RGNL AP, AR US (USW00013964).

Zone 8aUSDA average annual extreme minimum 10°F to 15°F, from ZIP 72903 (0.7 miles from the city point used on this page).

Median last 32°F is March 25. Median first 32°F is November 6. The 50% growing-season length is 224 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 4	Earlier date. A last 32°F on or after this day is common.
50%	March 25	Median.
10%	April 11	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 23	Earlier date. A first 32°F on or before this day is uncommon.
50%	November 6	Median.
90%	November 21	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%	248
50%	224
90%	202

28°F threshold

	10%	50%	90%
Last, on or after	April 2	March 11	February 21
First, on or before	November 1	November 17	December 4
Season at least	276 days	250 days	223 days

36°F threshold

	10%	50%	90%
Last, on or after	April 25	April 8	March 21
First, on or before	October 16	October 28	November 11
Season at least	223 days	203 days	183 days

Station FT SMITH RGNL AP, AR US (USW00013964). Completeness flag S, 27 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 136.9 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.

Questions

When is the last spring frost in Fort Smith, AR?: The median last 32°F date at the station on this page is March 25. NOAA’s 1991–2020 normals give a 50% chance the last spring minimum of 32°F or lower occurs on or after that date. The 90% date is March 4. The 10% date, the later one, is April 11. These are normals, not a forecast for this spring.
What USDA zone is Fort Smith, AR?: The zone on this page is 8a, from ZIP 72903 in the 2023 PRISM table of the USDA Plant Hardiness Zone Map. That ZIP is 0.7 miles from the city point. USDA defines the zone as the average annual extreme minimum, shown here as 10°F to 15°F. It is a winter-cold band, not a frost date and not a forecast.
How far away is the weather station?: The station named on this page is 1.2 miles from the city point in a straight line. Frost dates are 1991–2020 NOAA climate normals for that instrument. They are not a National Weather Service forecast for one night, and they are not the temperature in every yard. The page names the station so the miles stay attached to the dates.

Check a crop against this station

Fort Smith, AR

Zone 8aAverage annual extreme minimum 10°F to 15°F

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

Arkansas. Nearest qualified station: FT SMITH RGNL AP, AR US (USW00013964), 1.2 miles. Median last 32°F March 25. Median first 32°F November 6. The 50% growing-season length is 224 days.

Open the ZIP page

32°F probabilities at this station

	10%	50%	90%
Last 32°F on or after	April 11	March 25	March 4
First 32°F on or before	October 23	November 6	November 21

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 Arkansas 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.