What to do in Fort Smith now
Fort Smith is in the transition zone, where both cool- and warm-season lawns grow. Dates are typical for this spot, worked out from 23 years of weather at Fort Smith Regional Ap; each status uses this year's soil estimates.
Cool-season: tall fescue, Kentucky bluegrass, perennial ryegrass, fine fescue
- Crabgrass pre-emergent Closed Feb 19 Typical: Feb 22 – Mar 132-inch soil held 55°F for a week from Feb 19, so crabgrass was sprouting. Next window: about Feb 22 – Mar 13, 2027.
- Seed or overseed Seed now · about 14 days left Typical: Oct 15 – Nov 174-inch soil is 69°, inside the 55–70°F range where tall fescue and bluegrass sprout fastest. The window typically closes around Nov 17.
- Late-fall feeding Final feeding from about Dec 2 Typical: Dec 2 – Dec 19Not too late. Feed on your normal fall schedule; the last feeding of the year goes down when 4-inch soil falls to about 50°F (typically Dec 2) and before it reaches 40°F (typically Dec 19).
Warm-season: bermudagrass, zoysia, St. Augustine, centipede, bahia
- Crabgrass pre-emergent Closed Feb 19 Typical: Feb 22 – Mar 132-inch soil held 55°F for a week from Feb 19, so crabgrass was sprouting. Next window: about Feb 22 – Mar 13, 2027.
- Seed or sod Wait for late spring Typical: Apr 17 – Oct 15Warm-season seed needs 4-inch soil at 65°F or more, and seedlings need the rest of summer to establish. Next window opens about Apr 17.
- Fall pre-emergent (Poa annua) Germinating since Oct 20 Typical: By Oct 124-inch soil fell below 70°F on Oct 20, when annual bluegrass begins to sprout. A pre-emergent now only stops later flushes; plan to apply by about Oct 12 next year.
- Dormancy and last feeding Expected about Nov 17 Typical: Around Nov 17Warm-season grass slows and browns once 4-inch soil stays under 55°F, typically Nov 17. Make the last nitrogen feeding at least a month before that.
The last 60 days and the week ahead
Fort Smith soil is 10° warmer than normal for Nov 3, warmer than on 91% of those dates since 2005, and 13° warmer than a year ago.
The green line is our estimate of the daily average soil temperature 2 inches down, driven by temperatures at Fort Smith Regional Ap, 1.8 km from the city center. The dashed part runs the National Weather Service forecast through the same model. Hover or tap for any day.
2-inch soil, estimated From the NWS forecast Normal Normal range (8 years in 10)
Show the numbers
| Date | 2-inch soil | 4-inch soil | Air high / low | Normal (2 in) |
|---|---|---|---|---|
| Oct 21 | 64° | 67° | 80° / 48° | 63° |
| Oct 22 | 65° | 67° | 83° / 50° | 63° |
| Oct 23 | 65° | 67° | 83° / 51° | 63° |
| Oct 24 | 66° | 68° | 84° / 52° | 62° |
| Oct 25 | 67° | 68° | 82° / 53° | 62° |
| Oct 26 | 66° | 67° | 79° / 50° | 61° |
| Oct 27 | 67° | 68° | 80° / 56° | 61° |
| Oct 28 | 67° | 68° | 83° / 55° | 60° |
| Oct 29 | 68° | 69° | 82° / 58° | 59° |
| Oct 30 | 69° | 70° | 78° / 64° | 58° |
| Oct 31 | 67° | 69° | 67° / 61° | 58° |
| Nov 1 | 67° | 68° | 70° / 62° | 58° |
| Nov 2 | 68° | 69° | 82° / 61° | 58° |
| Nov 3 | 68° | 69° | 75° / 59° | 58° |
| Nov 4 (forecast) | 65° | 67° | 68° / 49° | 58° |
| Nov 5 (forecast) | 64° | 66° | 71° / 51° | 58° |
| Nov 6 (forecast) | 61° | 64° | 64° / 47° | 58° |
| Nov 7 (forecast) | 58° | 61° | 61° / 43° | 58° |
| Nov 8 (forecast) | 57° | 60° | 64° / 42° | 58° |
| Nov 9 (forecast) | 56° | 59° | 67° / 44° | 57° |
| Nov 10 (forecast) | 57° | 59° | 69° / 48° | 57° |
Which grass grows in Fort Smith
With January averaging 41°F, Fort Smith sits in the transition zone. Tall fescue is the common cool-season choice; bermudagrass and zoysia are the common warm-season ones. Use the switch above to see the calendar for yours.
Fort Smith soil through the year
Weekly 2-inch estimates for 2026 so far against 2025 and the normal for each week. The red lines mark 50°F, when crabgrass pre-emergent should be down, and 65°F, when warm-season seed sprouts well.
2026 2025 Normal (2005–2025) 8 years in 10
Normal by month
| Month | 2 in | 4 in | Air |
|---|---|---|---|
| Jan | 41° | 42° | 41° |
| Feb | 44° | 45° | 45° |
| Mar | 54° | 55° | 54° |
| Apr | 62° | 64° | 62° |
| May | 71° | 72° | 70° |
| Jun | 81° | 82° | 79° |
| Jul | 85° | 87° | 83° |
| Aug | 85° | 86° | 82° |
| Sep | 78° | 80° | 75° |
| Oct | 66° | 68° | 64° |
| Nov | 53° | 55° | 52° |
| Dec | 44° | 46° | 43° |
Soil: average of our daily estimates, 2005–2025. Air: NOAA 1991–2020 normals for the station.
Typical lawn dates in Fort Smith
Each date is when the soil estimate (or the air, for freezes) crossed the threshold, year by year since 2005. “Early” and “late” are the 10th and 90th percentile years, so 8 years in 10 fall between them.
| Event | Typical | 2026 |
|---|---|---|
| Last spring freeze (32°F) | Mar 23 | Mar 17 |
| Crabgrass model: 250 growing degree days | Jan 29 | Jan 14 |
| Pre-emergent window opens (2-inch soil 50°F) | Feb 22 | Feb 12 |
| Crabgrass begins to sprout (2-inch soil 55°F) | Mar 13 | Feb 19 |
| Cool-season lawns start growing (4-inch soil 55°F) | Mar 13 | Feb 18 |
| Warm-season seeding opens (4-inch soil 65°F) | Apr 17 | Mar 10 |
| Cool-season seeding opens (4-inch soil under 70°F) | Oct 15 | Oct 22 |
| Cool-season seeding ends (4-inch soil under 55°F) | Nov 17 | not yet |
| Warm-season grass goes dormant (4-inch under 55°F) | Nov 17 | not yet |
| First fall freeze (32°F) | Nov 9 | not yet |
| Roots stop feeding (4-inch soil under 40°F) (in 11 of 21 years) | Dec 19 | not yet |
Where these numbers come from
There is no soil sensor in most cities, so we estimate it. Shallow soil follows air temperature with a lag of a few days, and runs a little warmer than the air in fall. We fitted that relationship to 190 USDA soil-sensor stations; on years held out of the fit, the estimate was off by 3.3°F on an average day, and it put the spring 55°F date within a median of 3 days. Read the methodology.
Weather: RCC ACIS station KFSM (FORT SMITH REGIONAL AP), daily data since 1945. Forecast: National Weather Service, TSA office, issued Nov 4, 2026, 6:50 AM EST. Last observed day: Nov 3, 2026.
Fort Smith questions
What is the soil temperature in Fort Smith today? Our estimate for Nov 3 is 68°F at 2 inches and 69°F at 4 inches, as a daily average. Early-morning soil runs a few degrees cooler than that, and afternoon soil warmer.
When should I put down crabgrass pre-emergent in Fort Smith? Apply when 2-inch soil holds about 50°F and before it holds 55°F. That has typically been Feb 22 to Mar 13 in Fort Smith. For 2026 the window closed on Feb 19.
When can I seed bermudagrass in Fort Smith? Wait for late spring. Warm-season seed needs 4-inch soil at 65°F or more, and seedlings need the rest of summer to establish. Next window opens about Apr 17.
Is it too late to fertilize in Fort Smith? Expected about Nov 17. Warm-season grass slows and browns once 4-inch soil stays under 55°F, typically Nov 17. Make the last nitrogen feeding at least a month before that.
When is the last frost in Fort Smith? The last 32°F night of spring has typically come around Mar 23, and as late as Apr 15 in 1 year in 10. The first fall freeze typically arrives around Nov 9.
Why 2 inches and 4 inches? Crabgrass and most weed seeds sprout in the top inch or two, so pre-emergent timing follows 2-inch soil. Grass seed and roots respond to the slightly steadier soil at about 4 inches.
How accurate is this? It is a model, not a probe in your yard. Expect about 3–4°F of difference on a given day; shade, slope, mulch and irrigation all move real soil. The dates and trends are more reliable than any single day.