What is the soil temperature in ZIP code 52166 today?

About 49°F on average in the top 4 inches (0–10 cm), low 47°F and high 51°F, from NOAA's GFS model run of Nov 11, 12:00 UTC (7 am Eastern). It is a model value for a grid cell 9.2 km from the ZIP centre, not a reading from your yard.

Is it time for crabgrass preventer in 52166?

The spring window is closed. It opens again when the soil holds 50°F. Last spring the soil held 50°F from May 12 and 55°F from May 25.

ZIP 52166 · Decorah, IA · Nov 11, 2026

Soil temperature for ZIP code 52166

49°Faverage today, 0–4 in deep (modelled)
low 47°F · high 51°F

Modelled by NOAA GFS, not measured · run Nov 11, 12:00 UTC (7 am Eastern) · grid cell 9.2 km from the ZIP centre point

On a week ago

6° cooler

55°F on Nov 4

5-day mean

46°F

what the verdicts use

Held 55°F last spring

May 25

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, modelled. Dots and line: daily average (dashed = forecast); bars: low to high; green band: 50–55°F.

View as table

Day	Average	Low	High
Nov 4	55.0°F	50.8°F	58.9°F	analysis
Nov 5	48.7°F	48.4°F	49.0°F	analysis
Nov 6	43.5°F	41.3°F	45.8°F	analysis
Nov 7	41.2°F	38.0°F	44.6°F	analysis
Nov 8	44.5°F	41.8°F	48.1°F	analysis
Nov 9	45.5°F	42.2°F	49.7°F	analysis
Nov 10	48.0°F	44.5°F	51.3°F	analysis
Today	49.2°F	47.4°F	51.4°F	analysis
Nov 12	43.5°F	42.2°F	47.1°F	forecast
Nov 13	37.7°F	36.7°F	39.2°F	forecast
Nov 14	35.7°F	34.7°F	36.6°F	forecast
Nov 15	36.2°F	35.3°F	38.0°F	forecast
Nov 16	37.2°F	35.9°F	40.4°F	forecast
Nov 17	39.2°F	36.1°F	42.7°F	forecast

Source: NOAA NCEP GFS 0.25°, 0–10 cm soil temperature, run Nov 11, 12:00 UTC (7 am Eastern).

Spring 2026 threshold dates

From the 5-day mean held for 10 days or more.

Soil	What it means	Held from (spring 2026)
40°F	Peas and lettuce	Mar 22
50°F	Pre-emergent window opens	May 12
55°F	Crabgrass can germinate	May 25
60°F	Tomatoes	May 27
65°F	Warm-season grass seed	not reached

Waterloo, IA, 72 km away: the full city page, with the 2026 season chart, growing degree days and nearby cities →

Nearby ZIP codes

Today's modelled average.

52144 49°F · 52171 49°F · 52175 49°F · 52147 49°F · 52168 49°F · 52132 49°F · 52161 49°F · 52154 50°F

More: crabgrass timing in Iowa · every Iowa city · how accurate the model is.

Questions

What is the soil temperature in ZIP code 52166 today?: About 49°F on average in the top 4 inches (0–10 cm), low 47°F and high 51°F, from NOAA's GFS model run of Nov 11, 12:00 UTC (7 am Eastern). It is a model value for a grid cell 9.2 km from the ZIP centre, not a reading from your yard.
Is it time for crabgrass preventer in 52166?: The spring window is closed. It opens again when the soil holds 50°F. Last spring the soil held 50°F from May 12 and 55°F from May 25.

Data: Global Forecast System (GFS) 0.25°, soil temperature 0–10 cm (TSOIL) (NOAA National Centers for Environmental Prediction (NCEP)); 2025 Gazetteer ZIP Code Tabulation Areas (ZCTA) and 2024 cartographic boundary state outlines (U.S. Census Bureau).