What to do in San Francisco now
San Francisco is in warm-season grass country. Dates are typical for this spot, worked out from 23 years of weather at Oakland International Airport; each status uses this year's soil estimates.
Cool-season: tall fescue, Kentucky bluegrass, perennial ryegrass, fine fescue
- Crabgrass pre-emergent Closed Feb 28 Typical: early Feb – Mar 172-inch soil held 55°F for a week from Feb 28, so crabgrass was sprouting. Next window: about Feb 1 – Mar 17, 2027.
- Seed or overseed Seed now · about 26 days left Typical: Aug 10 – Nov 294-inch soil is 58°, inside the 55–70°F range where tall fescue and bluegrass sprout fastest. The window typically closes around Nov 29.
- Late-fall feeding Soil rarely cools to 40°F Typical: Through winterRoots stay active through most winters here. Feed on the fall schedule your extension office gives for your grass, and avoid feeding a lawn that is dormant from drought.
Warm-season: bermudagrass, zoysia, St. Augustine, centipede, bahia
- Crabgrass pre-emergent Closed Feb 28 Typical: early Feb – Mar 172-inch soil held 55°F for a week from Feb 28, so crabgrass was sprouting. Next window: about Feb 1 – Mar 17, 2027.
- Seed or sod Wait for late spring Typical: Jun 7 – Aug 10Warm-season seed needs 4-inch soil at 65°F or more, and seedlings need the rest of summer to establish. Next window opens about Jun 7.
- Fall pre-emergent (Poa annua) Germinating since Aug 10 Typical: By Aug 104-inch soil fell below 70°F on Aug 10, when annual bluegrass begins to sprout. A pre-emergent now only stops later flushes; plan to apply by about Aug 10 next year.
- Dormancy and last feeding Expected about Nov 29 Typical: Around Nov 29Warm-season grass slows and browns once 4-inch soil stays under 55°F, typically Nov 29. Make the last nitrogen feeding at least a month before that.
The last 60 days and the week ahead
San Francisco soil is 2° cooler than normal for Nov 3, cooler than on 81% of those dates since 2005, and 2° cooler than a year ago.
The green line is our estimate of the daily average soil temperature 2 inches down, driven by temperatures at Oakland International Airport, 17.6 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 20 | 62° | 64° | 69° / 52° | 63° |
| Oct 21 | 62° | 64° | 69° / 53° | 63° |
| Oct 22 | 61° | 63° | 63° / 57° | 62° |
| Oct 23 | 61° | 63° | 69° / 52° | 62° |
| Oct 24 | 60° | 62° | 72° / 46° | 62° |
| Oct 25 | 60° | 62° | 72° / 47° | 62° |
| Oct 26 | 61° | 62° | 68° / 57° | 62° |
| Oct 27 | 60° | 61° | 65° / 48° | 61° |
| Oct 28 | 59° | 61° | 70° / 45° | 61° |
| Oct 29 | 58° | 60° | 68° / 47° | 61° |
| Oct 30 | 59° | 60° | 66° / 52° | 60° |
| Oct 31 | 58° | 60° | 65° / 48° | 60° |
| Nov 1 | 57° | 59° | 65° / 47° | 60° |
| Nov 2 | 57° | 59° | 65° / 47° | 59° |
| Nov 3 | 57° | 58° | 65° / 48° | 59° |
| Nov 4 (forecast) | 57° | 59° | 66° / 53° | 59° |
| Nov 5 (forecast) | 58° | 60° | 69° / 53° | 59° |
| Nov 6 (forecast) | 59° | 60° | 70° / 53° | 58° |
| Nov 7 (forecast) | 61° | 61° | 73° / 55° | 58° |
| Nov 8 (forecast) | 61° | 62° | 69° / 56° | 58° |
| Nov 9 (forecast) | 61° | 62° | 68° / 55° | 57° |
Which grass grows in San Francisco
With mild winters (January averages 50°F), most San Francisco lawns are warm-season grasses such as bermudagrass, St. Augustine, zoysia and centipede. They grow through summer and slow or go dormant in winter.
San Francisco 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 | 49° | 51° | 50° |
| Feb | 52° | 53° | 53° |
| Mar | 54° | 56° | 55° |
| Apr | 58° | 59° | 57° |
| May | 61° | 62° | 60° |
| Jun | 64° | 66° | 63° |
| Jul | 66° | 67° | 64° |
| Aug | 66° | 68° | 65° |
| Sep | 67° | 68° | 65° |
| Oct | 63° | 65° | 61° |
| Nov | 56° | 57° | 55° |
| Dec | 50° | 51° | 50° |
Soil: average of our daily estimates, 2005–2025. Air: NOAA 1991–2020 normals for the station.
Typical lawn dates in San Francisco
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 |
|---|---|---|
| Crabgrass model: 250 growing degree days | Jan 15 | Jan 13 |
| Pre-emergent window opens (2-inch soil 50°F) | early Feb | Feb 1 |
| Crabgrass begins to sprout (2-inch soil 55°F) | Mar 17 | Feb 28 |
| Cool-season lawns start growing (4-inch soil 55°F) | Feb 21 | Feb 11 |
| Warm-season seeding opens (4-inch soil 65°F) | Jun 7 | Mar 22 |
| Cool-season seeding opens (4-inch soil under 70°F) | Aug 10 | Aug 10 |
| Cool-season seeding ends (4-inch soil under 55°F) | Nov 29 | not yet |
| Warm-season grass goes dormant (4-inch under 55°F) | Nov 29 | 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 KOAK (OAKLAND INTERNATIONAL AIRPORT), daily data since 1948. Forecast: National Weather Service, MTR office, issued Nov 4, 2026, 4:21 AM EST. Last observed day: Nov 3, 2026.
San Francisco questions
What is the soil temperature in San Francisco today? Our estimate for Nov 3 is 57°F at 2 inches and 58°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 San Francisco? Apply when 2-inch soil holds about 50°F and before it holds 55°F. That has typically been early Feb to Mar 17 in San Francisco. For 2026 the window closed on Feb 28.
When can I seed bermudagrass in San Francisco? 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 Jun 7.
Is it too late to fertilize in San Francisco? Expected about Nov 29. Warm-season grass slows and browns once 4-inch soil stays under 55°F, typically Nov 29. Make the last nitrogen feeding at least a month before that.
When is the last frost in San Francisco? The last 32°F night of spring has typically come around Jan 18, and as late as Feb 21 in 1 year in 10. The first fall freeze typically arrives around Dec 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.