New Haven, Connecticut · Nov 11, 2026
Soil temperature today in New Haven
low 50°F · high 58°F
Modelled by NOAA GFS · run Nov 11, 12:00 UTC (7 am Eastern) · grid cell 8.8 km from New Haven
What the soil says today
- Pre-emergentSeason over
- Cool-season seedToo late in the season
- Warm-season seedToo cold
- TomatoesToo cold
- Peas and lettuceWarm enough
From the 5-day mean of the modelled 0–4 in layer.
Soil temperature, 0–4 in: last 7 days and next 7
°F. Dots and line: daily average (dashed = forecast); bars: the day's low to high; green band: the 50–55°F pre-emergent window.
- Daily average
- Low to high
- 50–55°F window
View as table
| Day | Average | Low | High | |
|---|---|---|---|---|
| Nov 4 | 61.4°F | 56.2°F | 66.0°F | analysis |
| Nov 5 | 62.9°F | 58.9°F | 66.3°F | analysis |
| Nov 6 | 63.4°F | 62.8°F | 64.0°F | analysis |
| Nov 7 | 60.4°F | 57.3°F | 64.0°F | analysis |
| Nov 8 | 54.7°F | 51.5°F | 57.9°F | analysis |
| Nov 9 | 53.4°F | 51.2°F | 55.3°F | analysis |
| Nov 10 | 52.5°F | 47.6°F | 56.8°F | analysis |
| Today | 54.7°F | 50.3°F | 58.5°F | forecast |
| Nov 12 | 53.2°F | 51.7°F | 55.5°F | forecast |
| Nov 13 | 45.2°F | 43.2°F | 48.9°F | forecast |
| Nov 14 | 42.7°F | 40.6°F | 44.9°F | forecast |
| Nov 15 | 42.3°F | 38.0°F | 46.8°F | forecast |
| Nov 16 | 43.5°F | 38.8°F | 48.2°F | forecast |
| Nov 17 | 43.6°F | 38.2°F | 48.4°F | forecast |
What the soil says for each job
Today's verdicts use the 5-day mean of the modelled 0–4 in layer.
| Job | Soil rule | Today |
|---|---|---|
| Crabgrass pre-emergent | Apply while the soil holds 50 to 55°F, before crabgrass germinates at about 55°F | Season over The spring window is closed. It opens again when the soil holds 50°F. Last spring the soil held 50°F from Apr 27 and 55°F from May 13. |
| Seed or overseed cool-season grass | Fescue, bluegrass and ryegrass germinate best in soil of 50 to 65°F | Too late in the season Past the usual Aug 15 to Oct 15 seeding window (55°F soil today). |
| Seed warm-season grass | Bermuda, zoysia and centipede need soil of 65°F or more | Too cold 55°F: under 65°F. |
| Plant out tomatoes | Tomato roots want soil of 60°F or more (check your frost date as well) | Too cold 55°F: under 60°F. |
| Sow peas, lettuce and spinach | Cool-weather crops germinate once soil reaches about 40°F | Warm enough 55°F: at or over 40°F. |
The 2026 season so far
°F, daily average of the 0–4 in layer since 1 January (dashed = forecast). Dots: the days the soil began to hold 50°F and 55°F.
- Daily average
- 50–55°F window
When the soil crossed each threshold
2026, from the 5-day mean held for 10 days or more.
| Soil | What it means | Held from (spring 2026) | Fell below (autumn 2026) |
|---|---|---|---|
| 40°F | Peas and lettuce can be sown | Mar 11 | not yet |
| 50°F | Pre-emergent window opens | Apr 27 | not yet |
| 55°F | Crabgrass can germinate | May 13 | not yet |
| 60°F | Warm enough for tomatoes | Jun 4 | Oct 18 |
| 65°F | Warm-season grass seed | Jun 5 | Sep 22 |
Growing degree days in New Haven
Base 50°F, from 1 January to Nov 8, at the Guilford station (21.6 km).
A growing degree day is each degree that the day's average temperature runs above 50°F. Insects, weeds and crops develop by accumulated GDD, so the number says how far the season has run. Every city.
Soil temperature nearby
Each from a different model grid cell.
| City | Distance | Soil today | vs a week ago | Grass seed |
|---|---|---|---|---|
| Bridgeport, CT | 26 km | 52°F | −7°F | Too late in the season |
| Madison, CT | 28 km | 52°F | −7°F | Too late in the season |
| Waterbury, CT | 30 km | 48°F | −8°F | Too late in the season |
| Danbury, CT | 45 km | 49°F | −7°F | Too late in the season |
| Hartford, CT | 55 km | 52°F | −9°F | Too late in the season |
| Stamford, CT | 58 km | 56°F | −6°F | Too late in the season |
This page also covers Hamden (10.1 km), West Haven (4.4 km), Shelton (13.8 km), Branford (10 km), East Haven (6.1 km), North Haven (10.8 km), Guilford (20.7 km), Ansonia (13.3 km), Wallingford Center (18.2 km), Wallingford (18.7 km) and 1 more: they share the same model grid cell area, within 25 km.
Questions
- What is the soil temperature in New Haven today?
- About 55°F on average in the top 4 inches (0–10 cm), with a low of 50°F and a high of 58°F, from NOAA's GFS model run of Nov 11, 12:00 UTC (7 am Eastern).
- Is it time to put down crabgrass preventer in New Haven?
- The spring window is closed. It opens again when the soil holds 50°F. Last spring the soil held 50°F from Apr 27 and 55°F from May 13.
- When did the soil in New Haven reach 55°F this year?
- The 5-day average held 55°F from May 13, 2026.
- How accurate is a modelled soil temperature?
- Against NOAA's 108 reference stations the model's daily average was off by 4.2°F on average, and within 5°F on 68% of days. A shaded, mulched or watered yard can differ more.
Data: Global Forecast System (GFS) 0.25°, soil temperature 0–10 cm (TSOIL) (NOAA National Centers for Environmental Prediction (NCEP)); U.S. Climate Reference Network (USCRN) hourly data, version 2 (soil temperature at 5 cm and 10 cm, air temperature) (NOAA National Centers for Environmental Information (NCEI)); Global Historical Climatology Network - Daily (GHCN-Daily), daily maximum and minimum temperature (NOAA National Centers for Environmental Information (NCEI)); GeoNames gazetteer (cities15000) (GeoNames).