Lewis and Clark County weather, town by town
18 places in Lewis and Clark County, Montana, each with its own live forecast and radar, and where a station sits close enough, measured weather records.
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Measured at the NOAA stations serving these towns, daily records 1896 to 2026. Station extremes, not official state records.
Lewis and Clark County Weather Facts
Lewis and Clark County has 18 places on myweatherrock (16 census-designated places, 2 cities), each with its own live forecast, hourly timeline, ten day outlook and radar. The hottest day in the station records is 108°F at Holter Dam on July 30, 1936. The coldest night is -55°F at Frohner Meadow on February 3, 1989. The wettest day brought 4.11 inches of rain at Augusta on May 30, 1897. The biggest single-day snow measured 18.82 inches at Helena Ap Asos on November 11, 1959. Those are station measurements from NOAA's daily records, 1896 to 2026, not official state records. By area the largest place is Helena Valley Northeast, about 53 square miles.
About Lewis and Clark County weather
The map on the Now tab shows every Lewis and Clark County town's current temperature from our own server, one dot per town. Tap any dot, or type a town above, for that town's full forecast.
What the weather is usually like
Across the 18 Lewis and Clark County towns with station normals, the warmest month is July, when the day usually reaches 83°F, and the coldest is January, when the night usually falls to 15°F. June is the wettest, with rain on about 11 days. July afternoons run from about 71°F in Canyon Creek to 87°F in Craig. January nights run from about 12°F in Lincoln to 20°F in Craig.
Means of the 1991 to 2020 station normals serving these towns, as published by NOAA; each town's page carries its own.
Where these numbers come from
- Current conditions and forecast: NOAA forecast grids decoded on our own server, corrected against the nearest reporting station and our own radar. Open-Meteo is consulted only as a fallback when our server is silent.
- Records: computed by myweatherrock from NOAA GHCN-Daily station records at the stations serving these towns. Measurements, not estimates.
- Warnings and alerts: the National Weather Service, passed through unchanged.
Lewis and Clark County weather records
Measured at the NOAA stations serving these towns, daily records 1896 to 2026. Station extremes, not official state records.
Common questions about Lewis and Clark County weather
- What is the hottest temperature recorded at a Lewis and Clark County station?
- 108°F at Holter Dam on July 30, 1936, in the NOAA daily station records myweatherrock holds (1896 to 2026).
- What is the coldest temperature recorded at a Lewis and Clark County station?
- -55°F at Frohner Meadow on February 3, 1989.
- What is the most rain a Lewis and Clark County station has measured in one day?
- 4.11 inches at Augusta on May 30, 1897.
- What is the biggest one-day snowfall at a Lewis and Clark County station?
- 18.82 inches at Helena Ap Asos on November 11, 1959.
- How many Lewis and Clark County towns have a weather page here?
- 18: 16 census-designated places, 2 cities. Each page carries current conditions, the hourly timeline, the ten day outlook, radar, and where a station sits close enough, measured records.
- Where does the Lewis and Clark County forecast come from?
- NOAA forecast grids (the National Weather Service digital forecast, the National Blend of Models, HRRR and GFS) decoded on our own server, corrected against the nearest reporting station and our own radar. Open-Meteo is consulted only as a fallback when our server is silent.
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