Lewistown, Montana Weather
Lewistown weather this week
Over the next 7 days in Lewistown, daytime highs range from 3°C to 20°C and night-time lows from -3°C to 6°C. The warmest afternoon is likely today at 20°C, while the coolest night is expected on Wednesday night at -3°C. Temperatures trend cooler through the week, dropping by about 13°C. Expect a wide gap of around 14°C between afternoon and early-morning temperatures, so mornings will feel noticeably cooler.
Rain is most likely Tuesday and Wednesday, with roughly 7.4 mm forecast in total over the week. Snowfall is in the forecast Thursday; check road conditions before travelling.
Winds stay mostly light this week, peaking at about 22 km/h tomorrow. UV levels stay moderate or lower, peaking at 3. Average humidity is a comfortable 55% or so.
| Day | Conditions | High / Low | Rain chance | Rain | Max wind |
|---|---|---|---|---|---|
| Today (Friday) | Overcast | 20° / 6° | 0% | 0.0 mm | 21 km/h |
| Tomorrow (Saturday) | Overcast | 17° / 5° | 2% | 0.0 mm | 22 km/h |
| Sunday | Overcast | 15° / 2° | 2% | 0.0 mm | 14 km/h |
| Monday | Overcast | 15° / 6° | 8% | 0.0 mm | 8 km/h |
| Tuesday | Dense drizzle | 6° / 1° | 49% | 6.5 mm | 10 km/h |
| Wednesday | Light drizzle | 4° / -3° | 62% | 0.3 mm | 12 km/h |
| Thursday | Slight snow | 3° / -2° | 21% | 0.6 mm | 18 km/h |
Hourly forecast in Lewistown
16-day forecast for Lewistown
Check any date
Lewistown air quality & conditions
Air quality index
Today's outlook for Lewistown
At 18:00 local time it is 12°C in Lewistown under clear skies, feeling like 6°C. Today's forecast high is 20°C and the low is 6°C, and the day overall looks overcast. Rain is unlikely today (0% chance). Winds are blowing at about 15 km/h from the south-west. Humidity is 27%.
Explore nearby
Weather articles
Weather news
Climate of Lewistown: monthly averages
Based on 25 years of satellite and reanalysis data (2001-2025), July is usually the hottest month in Lewistown, with average daytime highs around 28°C. February is the coolest, when nights typically fall to about -10°C and frost is possible on the coldest nights. That is a wide yearly range of roughly 38°C, so the seasons feel very different from each other.
The area receives about 520 mm of rain in a typical year. Rainfall is modest in every month; May is the wettest at about 89 mm.
For outdoor plans and travel, June to September usually offer the most comfortable weather in Lewistown, with mild days and relatively little rain.
| Month | Avg high | Avg low | Rainfall | Humidity |
|---|---|---|---|---|
| Jan | -1° | -10° | 21 mm | 81% |
| Feb | 0° | -10° | 23 mm | 78% |
| Mar | 5° | -6° | 28 mm | 71% |
| Apr | 10° | -2° | 56 mm | 66% |
| May | 16° | 3° | 89 mm | 64% |
| Jun | 22° | 8° | 84 mm | 61% |
| Jul | 28° | 13° | 40 mm | 51% |
| Aug | 26° | 11° | 43 mm | 51% |
| Sep | 19° | 6° | 43 mm | 58% |
| Oct | 11° | -1° | 44 mm | 68% |
| Nov | 4° | -5° | 23 mm | 73% |
| Dec | -1° | -10° | 22 mm | 80% |
Source: NASA POWER (MERRA-2 reanalysis), averaged over the roughly 50 km grid area around Lewistown. Values describe typical conditions, not a forecast.
About Lewistown weather
Lewistown is a place in Montana's continental climate, ranging from northern plains to Rocky Mountain terrain, located about 159 km north-west of Billings. Lewistown gets warm days and cool nights (June–August) each year. Lewistown closes out the year with long, cold winters with heavy mountain snowfall. This page shows live, auto-refreshing weather for Lewistown: current conditions, an hourly breakdown, a 16-day outlook, a date-lookup tool for any past or future date, and real-time air quality, sourced from Open-Meteo. Local timezone: America/Denver.
Frequently asked questions
Lewistown is about 159 km north-west of Billings, in Montana.
Lewistown sees long, cold winters with heavy mountain snowfall.
The live current conditions, hourly forecast and 16-day outlook above are pulled in real time for Lewistown's exact coordinates. No fixed schedule, the page updates whenever you load it.
July is usually the hottest month in Lewistown, with average daytime highs of about 28°C and nights around 13°C.
The coldest nights come in February, when the average low is about -10°C and daytime highs reach around 0°C. Frost is possible on clear, calm nights.
Lewistown receives about 520 mm of rain in a typical year. May is the wettest month at roughly 89 mm; no month averages more than 100 mm.
June to September usually offer the most comfortable weather in Lewistown, with mild daytime temperatures and little rain.
In November Lewistown typically sees daytime highs near 4°C and lows near -5°C, with about 23 mm of rain over the month and average humidity around 73%. Check the live forecast above for this week's actual conditions.
Up to 16 days ahead using the extended forecast and date picker above; further-out or historical dates use the same date lookup tool.
The current temperature for Lewistown updates automatically at the top of this page — scroll to the hourly strip below to see how it's expected to change over the day.
Lewistown's day-to-day weather follows the broader pattern of Montana described above. See the hourly weather forecast or the air quality index for more detail.