Monthly weather forecast and climate
Lewistown, MT

Weather in January

January, like December, is a freezing cold winter month in Lewistown, Montana, with average temperature varying between 30.6°F (-0.8°C) and 16.9°F (-8.4°C). In January, the average high-temperature is practically the same as in December - a still subzero cold 30.6°F (-0.8°C). Weather in January »

Weather in February

February, the last month of the winter, in Lewistown, is another freezing cold month, with average temperature ranging between max 29.1°F (-1.6°C) and min 15.3°F (-9.3°C). The coldest months are February and December, with an average high-temperature of 29.1°F (-1.6°C). Weather in February »

Weather in March

The first month of the spring, March, is a wintry month in Lewistown, Montana, with average temperature varying between 25.3°F (-3.7°C) and 40.6°F (4.8°C). In Lewistown, the average high-temperature in March rises, from a freezing cold 29.1°F (-1.6°C) in February, to a cold 40.6°F (4.8°C). Weather in March »

Weather in April

April in Lewistown, Montana, is a chilly spring month, with average temperature ranging between min 31.8°F (-0.1°C) and max 47.8°F (8.8°C). In April, the average high-temperature slightly increases, from a wintry 40.6°F (4.8°C) in March, to a chilly 47.8°F (8.8°C). Weather in April »

Weather in May

May, the last month of the spring, in Lewistown, is a moderate month, with average temperature ranging between min 40.1°F (4.5°C) and max 58.5°F (14.7°C). In Lewistown, Montana, the average high-temperature increases, from a frosty 47.8°F (8.8°C) in April, to a moderate 58.5°F (14.7°C). Weather in May »

Weather in June

June, the first month of the summer, in Lewistown, is a pleasant month, with average temperature varying between 47.8°F (8.8°C) and 68.5°F (20.3°C). In Lewistown, Montana, the average high-temperature rises, from a mild 58.5°F (14.7°C) in May, to a pleasant 68.5°F (20.3°C). Weather in June »

Weather in July

July is a warm summer month in Lewistown, Montana, with average temperature ranging between max 78.8°F (26°C) and min 54.3°F (12.4°C). The warmest month is July, with an average high-temperature of 78.8°F (26°C) and an average low-temperature of 54.3°F (12.4°C). Weather in July »

Weather in August

The last month of the summer, August, is another warm month in Lewistown, Montana, with average temperature ranging between max 78.1°F (25.6°C) and min 54.5°F (12.5°C). In Lewistown, Montana, the average high-temperature in August is essentially the same as in July - a still moderately hot 78.1°F (25.6°C). Weather in August »

Weather in September

The first month of the autumn, September, is also an enjoyable month in Lewistown, Montana, with average temperature ranging between min 47.1°F (8.4°C) and max 67.5°F (19.7°C). In September, the average high-temperature drops, from a moderately hot 78.1°F (25.6°C) in August, to an enjoyable 67.5°F (19.7°C). Weather in September »

Weather in October

October, like September, in Lewistown, Montana, is a cool autumn month, with average temperature fluctuating between 35.1°F (1.7°C) and 52.2°F (11.2°C). In Lewistown, the average high-temperature declines considerably, from an enjoyable 67.5°F (19.7°C) in September, to a fresh 52.2°F (11.2°C). Weather in October »

Weather in November

November, the last month of the autumn, in Lewistown, is also a wintry month, with average temperature fluctuating between 39.2°F (4°C) and 25.2°F (-3.8°C). In November, the average high-temperature drops, from a cool 52.2°F (11.2°C) in October, to a cold 39.2°F (4°C). Weather in November »

Weather in December

December, the first month of the winter, in Lewistown, is still a freezing cold month, with average temperature varying between 29.1°F (-1.6°C) and 16°F (-8.9°C). February and December, with an average high-temperature of 29.1°F (-1.6°C), are the coldest months. Weather in December »
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FAQ

How many days does it rain in Lewistown?

Throughout the year, in Lewistown, Montana, there are 126.2 rainfall days, and 17.83" (453mm) of precipitation is accumulated.

When does it snow in Lewistown?

January through June, September through December are months with snowfall in Lewistown, Montana.

How much does it snow in Lewistown?

In Lewistown, Montana, during the entire year, snow falls for 83.4 days, and aggregates up to 45.51" (1156mm) of snow.

What are the months with the lowest UV index in Lewistown?

January through April, October through December, with an average maximum UV index of 2, are months with the lowest UV index.

What are the coldest months in Lewistown?

February and December, with an average high-temperature of 29.1°F (-1.6°C), are the coldest months in Lewistown, Montana.

What is the most humid month in Lewistown?

With an average relative humidity of 79%, February is the most humid month in Lewistown, Montana.

What is the month with the least sunshine in Lewistown?

February has the least sunshine of the year, with an average of 5.5h of sunshine.

When does it snow the most in Lewistown?

April is the month with the most snowfall in Lewistown. Snow falls for 10 days and accumulates 9.13" (232mm) of snow.

What is the rainiest month in Lewistown?

May is the month with the most rainfall in Lewistown, Montana. Rain falls for 19.3 days and accumulates 3.39" (86mm) of precipitation.

When are the longest days in Lewistown?

With an average of 15.8h of daylight, June has the longest days of the year in Lewistown.

What is the warmest month in Lewistown?

The warmest month in Lewistown, Montana, is July, with an average high-temperature of 78.8°F (26°C) and an average low-temperature of 54.3°F (12.4°C).

When it does not snow in Lewistown?

July and August are months without snowfall.

What month has the most sunshine in Lewistown?

The month with the most sunshine is July, with an average of 11.8h of sunshine.

When is the highest UV index in Lewistown?

With an average maximum UV index of 6, July is the month with the highest UV index.

What is the least humid month in Lewistown?

The least humid month is August, with an average relative humidity of 47%.

What is the driest month in Lewistown?

December is the month with the least rainfall in Lewistown. Rain falls for 6 days and accumulates 0.71" (18mm) of precipitation.

What is the month with the shortest days in Lewistown?

With an average of 8.6h of daylight, December has the shortest days of the year in Lewistown, Montana.

Average temperature
Lewistown, MT

Average temperature - Lewistown, MT

The warmest month (with the highest average high temperature) is July (78.8°F).
Months with the lowest average high temperature are February and December (29.1°F).

The month with the highest average low temperature is August (54.5°F).
The coldest month (with the lowest average low temperature) is February (15.3°F).

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Average pressure
Lewistown, MT

Average pressure - Lewistown, MT

The month with the highest atmospheric pressure is January (30.13").
The month with the lowest atmospheric pressure is June (29.85").

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Average wind speed
Lewistown, MT

Average wind speed - Lewistown, MT

The windiest months (with the highest average wind speed) are January, April and October (9.9mph).
The calmest month (with the lowest average wind speed) is August (7.4mph).

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Average rainfall
Lewistown, MT

Average rainfall - Lewistown, MT

The wettest month (with the highest rainfall) is May (3.39").
The driest month (with the least rainfall) is December (0.71").

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Average rainfall days
Lewistown, MT

Average rainfall days - Lewistown, MT

The month with the highest number of rainy days is May (19.3 days).
The month with the least rainy days is January (5.4 days).

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Average snowfall
Lewistown, MT

Average snowfall - Lewistown, MT

The month with the highest snowfall is April (9.13").
Months with the least snowfall are July and August (0").

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Average snowfall days
Lewistown, MT

Average snowfall days - Lewistown, MT

The month with the highest number of snowfall days is February (15.2 days).
Months with the least snowfall days are July and August (0 days).

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Average daylight / Average sunshine
Lewistown, MT

Average daylight / Average sunshine - Lewistown, MT

The month with the longest days is June (Average daylight: 15.8h).
The month with the shortest days is December (Average daylight: 8.6h).

The month with the most sunshine is July (Average sunshine: 11.8h).
The month with the least sunshine is February (Average sunshine: 5.5h).

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Average sunshine days
Lewistown, MT

Average sunshine days - Lewistown, MT

The month with the most sunshine days is September (19.3 days).
The month with the least sunshine days is April (8.3 days).

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Average UV index
Lewistown, MT

Average UV index - Lewistown, MT

The month with the highest UV index is July (UV index 6).
Months with the lowest UV index are January, February, March, April, October, November and December (UV index 2).

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Average visibility
Lewistown, MT

Average visibility - Lewistown, MT

Months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).

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