ZIP 59728 · Helena, MT · Nov 11, 2026

Soil temperature for ZIP code 59728

42°Faverage today, 0–4 in deep (modelled)
low 41°F · high 46°F

Modelled by NOAA GFS, not measured · run Nov 11, 12:00 UTC (7 am Eastern) · grid cell 5.1 km from the ZIP centre point

On a week ago
7° warmer
36°F on Nov 4
5-day mean
41°F
what the verdicts use
Held 55°F last spring
–
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.

20°30°40°50°60°50–55°F windowNov 4Nov 6Nov 8TodayNov 14Nov 1636°42°37°
View as table
DayAverageLowHigh
Nov 435.6°F34.7°F36.9°Fanalysis
Nov 535.7°F34.5°F37.1°Fanalysis
Nov 635.1°F33.8°F36.8°Fanalysis
Nov 739.0°F36.1°F44.8°Fanalysis
Nov 843.1°F40.7°F46.5°Fanalysis
Nov 939.3°F36.6°F42.3°Fanalysis
Nov 1040.2°F38.4°F43.2°Fanalysis
Today42.4°F40.9°F45.9°Fanalysis
Nov 1243.9°F41.8°F47.2°Fforecast
Nov 1342.6°F40.6°F45.2°Fforecast
Nov 1441.5°F40.0°F42.8°Fforecast
Nov 1537.3°F35.0°F40.3°Fforecast
Nov 1637.7°F35.5°F40.8°Fforecast
Nov 1736.9°F35.5°F38.4°Fforecast
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.

SoilWhat it meansHeld from (spring 2026)
40°FPeas and lettuceApr 7
50°FPre-emergent window opensJun 16
55°FCrabgrass can germinatenot reached
60°FTomatoesnot reached
65°FWarm-season grass seednot reached

Helena, MT, 32 km away: the full city page, with the 2026 season chart, growing degree days and nearby cities →

Nearby ZIP codes

Today's modelled average.

59601 43°F · 59713 42°F · 59631 40°F · 59731 42°F · 59636 47°F · 59640 43°F · 59722 43°F · 59623 47°F

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

Questions

What is the soil temperature in ZIP code 59728 today?
About 42°F on average in the top 4 inches (0–10 cm), low 41°F and high 46°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 5.1 km from the ZIP centre, not a reading from your yard.
Is it time for crabgrass preventer in 59728?
The spring window is closed. It opens again when the soil holds 50°F.

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).