Freeport, Illinois · Nov 11, 2026

Soil temperature today in Freeport

48°Faverage today, 0–4 in deep
low 47°F · high 49°F

Modelled by NOAA GFS · run Nov 11, 12:00 UTC (7 am Eastern) · grid cell 11.2 km from Freeport

On a week ago
11° cooler
59°F on Nov 4
Next 7 days
37–44°F
range of the daily averages forecast
Crabgrass pre-emergent
Season over
next window: when the soil holds 50°F
Held 55°F last spring
May 16
crabgrass germination temperature

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.

30°40°50°60°70°50–55°F windowNov 456789101112131415161759°40°
30°40°50°60°70°50–55°F windowNov 4Nov 6Nov 8Nov 10Nov 12Nov 14Nov 1659°40°
  • Daily average
  • Low to high
  • 50–55°F window
View as table
DayAverageLowHigh
Nov 458.7°F55.6°F61.5°Fanalysis
Nov 551.6°F50.7°F53.4°Fanalysis
Nov 646.4°F44.9°F49.2°Fanalysis
Nov 741.9°F38.8°F45.0°Fanalysis
Nov 844.7°F41.3°F49.2°Fanalysis
Nov 946.8°F43.2°F50.3°Fanalysis
Nov 1049.4°F46.2°F52.8°Fanalysis
Today47.5°F46.7°F48.7°Fforecast
Nov 1243.5°F42.0°F45.8°Fforecast
Nov 1337.7°F37.0°F38.2°Fforecast
Nov 1436.6°F35.2°F38.8°Fforecast
Nov 1538.2°F36.4°F41.0°Fforecast
Nov 1638.7°F36.1°F41.9°Fforecast
Nov 1739.7°F36.4°F42.9°Fforecast
Source: NOAA NCEP GFS 0.25°, 0–10 cm soil temperature, grid cell at 42.25°N 89.50°W. Run Nov 11, 12:00 UTC (7 am Eastern).

What the soil says for each job

Today's verdicts use the 5-day mean of the modelled 0–4 in layer.

JobSoil ruleToday
Crabgrass pre-emergentApply while the soil holds 50 to 55°F, before crabgrass germinates at about 55°FSeason over
The spring window is closed. It opens again when the soil holds 50°F. Last spring the soil held 50°F from Apr 13 and 55°F from May 16.
Seed or overseed cool-season grassFescue, bluegrass and ryegrass germinate best in soil of 50 to 65°FToo late in the season
Past the usual Aug 15 to Oct 15 seeding window (46°F soil today).
Seed warm-season grassBermuda, zoysia and centipede need soil of 65°F or moreToo cold
46°F: under 65°F.
Plant out tomatoesTomato roots want soil of 60°F or more (check your frost date as well)Too cold
46°F: under 60°F.
Sow peas, lettuce and spinachCool-weather crops germinate once soil reaches about 40°FWarm enough
46°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.

0°10°20°30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecHeld 50°F from Apr 1350° Apr 13Held 55°F from May 1655° May 16
0°10°20°30°40°50°60°70°80°JMMJSNHeld 50°F from Apr 1350° Apr 13Held 55°F from May 1655° May 16
  • Daily average
  • 50–55°F window
Source: NOAA NCEP GFS analyses, 4 a day. Dates use the 5-day mean, held for 10 days or more.

When the soil crossed each threshold

2026, from the 5-day mean held for 10 days or more.

SoilWhat it meansHeld from (spring 2026)Fell below (autumn 2026)
40°FPeas and lettuce can be sownMar 21not yet
50°FPre-emergent window opensApr 13not yet
55°FCrabgrass can germinateMay 16not yet
60°FWarm enough for tomatoesMay 26Sep 24
65°FWarm-season grass seednot reachedSep 15

Growing degree days in Freeport

Base 50°F, from 1 January to Nov 8, at the Freeport Wwtp station (1.4 km).

GDD in 2026
3,340
to Nov 8
Same date in 2025
3,139
201 more this year
All of 2025
3,140
full-year total

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.

CityDistanceSoil todayvs a week agoGrass seed
Rockford, IL43 km48°F−12°FToo late in the season
Dixon, IL52 km49°F−11°FToo late in the season
Janesville, WI65 km48°F−11°FToo late in the season
Clinton, IA69 km49°F−10°FToo late in the season
DeKalb, IL83 km48°F−12°FToo late in the season
Madison, WI88 km48°F−10°FToo late in the season

Questions

What is the soil temperature in Freeport today?
About 48°F on average in the top 4 inches (0–10 cm), with a low of 47°F and a high of 49°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 Freeport?
The spring window is closed. It opens again when the soil holds 50°F. Last spring the soil held 50°F from Apr 13 and 55°F from May 16.
When did the soil in Freeport reach 55°F this year?
The 5-day average held 55°F from May 16, 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).