Lewistown weather live forecast

Today's maximum temperature in Lewistown is expected to be 17°C. Select a day from the live weather forecast for Lewistown, Montana, USA for more weather parameters.

Monday
3rd Aug
17

6

9

5
Tuesday
4th Aug
22

4

11

7
Wednesday
5th Aug
27

7

14

8
Thursday
6th Aug
31

9

14

8
Friday
7th Aug
33

12

14

7

5-day weather forecast updated at 04:03 on Monday 3rd August 2026 GMT

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The 5-day weather forecast for Montana (Lewistown) is provided by the Swiss meteorological agency, meteoblue. Find out more about our data sources.

Lewistown weather forecast by day

Below are the detailed weather forecasts for Lewistown for the next 5 days.

Lewistown weather for Monday 3rd August 2026

Expect sunshine and showers in Lewistown, Montana with a maximum temperature of 17°C, maximum UV of 5 (Moderate) and 9 hours of bright sunshine. There are 0-2 mm of rainfall expected with 18% chance of some rain and a moderate breeze of 25 kph from the north-west.

17
°C maximum temperature
6
°C minimum temperature
sunshine and showers
9
hours of sunshine
5
UV index (Moderate)
18
% chance of some rain
<2
mm of rainfall expected
0
no heat & humidity
25
kph wind from NW

Lewistown weather for Tuesday 4th August 2026

Expect scattered clouds in Lewistown, Montana with a maximum temperature of 22°C, maximum UV of 7 (High) and 11 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 9 kph from the north.

22
°C maximum temperature
4
°C minimum temperature
scattered clouds
11
hours of sunshine
7
UV index (High)
0
mm of rainfall expected
0
no heat & humidity
9
kph wind from N

Lewistown weather for Wednesday 5th August 2026

Expect clear skies in Lewistown, Montana with a maximum temperature of 27°C, maximum UV of 8 (Very High) and 14 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 10 kph from the north-west.

27
°C maximum temperature
7
°C minimum temperature
clear skies
14
hours of sunshine
8
UV index (Very High)
0
mm of rainfall expected
27
°C wind chill
10
kph wind from NW

Lewistown weather for Thursday 6th August 2026

Expect clear skies in Lewistown, Montana with a maximum temperature of 31°C, moderate levels of heat & humidity, maximum UV of 8 (Very High) and 14 hours of bright sunshine. There are 0 mm of rainfall expected and a light breeze of 11 kph from the south.

31
°C maximum temperature
9
°C minimum temperature
clear skies
14
hours of sunshine
8
UV index (Very High)
0
mm of rainfall expected
M
moderate heat & humidity
11
kph wind from S

Lewistown weather for Friday 7th August 2026

Expect clear skies in Lewistown, Montana with a maximum temperature of 33°C, moderate levels of heat & humidity, maximum UV of 7 (High) and 14 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 15 kph from the north-west.