WEATHER IN Lewistown
Monthly temperature
| Month | Record low | Average low | Average | Average high | Record high |
| january | -46 (1929) | 12.9 | 23.7 | 34.4 | 73 (1981) |
| february | -42 (1936) | 13.9 | 24.6 | 35.3 | 70 (1932) |
| march | -28 (1896) | 21.4 | 32.9 | 44.3 | 88 (1902) |
| april | -17 (1936) | 28.8 | 40.9 | 53.0 | 89 (1939) |
| may | 11 (1929) | 37.4 | 50.0 | 62.6 | 98 (1931) |
| june | 21 (1914) | 45.1 | 58.0 | 71.0 | 105 (1900) |
| july | 27 (1903) | 50.7 | 66.1 | 81.6 | 105 (1900) |
| august | 27 (1910) | 49.6 | 65.4 | 81.1 | 103 (1961) |
| september | 6 (1926) | 41.5 | 55.9 | 70.4 | 99 (1909) |
| october | -10 (1935) | 30.8 | 43.4 | 56.0 | 92 (1905) |
| november | -30 (1985) | 20.9 | 32.1 | 43.4 | 81 (1908) |
| december | -42 (1983) | 13.6 | 24.3 | 35.0 | 74 (1939) |
| year | -46 (1929) | 30.6 | 43.0 | 55.5 | 105 (1900) |
Monthly precipitation
| Month | Average | Record low | Record high | Daily high |
| january | 0.58 | 0.01 (1901) | 2.75 (1978) | 0.87 (1978) |
| february | 0.49 | 0.02 (1901) | 2.22 (1914) | 2.02 (1914) |
| march | 0.87 | 0.16 (1900) | 3.16 (1898) | 1.25 (1995) |
| april | 1.71 | 0.09 (1949) | 3.90 (1896) | 1.73 (1927) |
| may | 2.88 | 0.20 (1900) | 9.16 (1981) | 2.81 (1962) |
| june | 3.35 | 0.50 (1904) | 10.96 (1944) | 3.10 (1906) |
| july | 1.76 | 0.04 (1908) | 5.97 (1928) | 2.80 (1907) |
| august | 1.69 | 0.02 (1901) | 5.54 (1985) | 2.99 (2002) |
| september | 1.39 | 0.00 (1990) | 4.92 (1941) | 1.76 (1959) |
| october | 1.27 | 0.01 (1902) | 5.80 (1908) | 3.80 (1908) |
| november | 0.67 | 0.01 (1907) | 3.97 (1897) | 1.80 (1896) |
| december | 0.51 | 0.00 (1905) | 4.76 (1917) | 0.96 (1937) |
| year | 16.85 | 9.38 (2004) | 28.12 (1978) | 3.80 (1908) |
Number of days with solid, liquid, and mixed precipitation
| Type of precipitation | jan | feb | mar | apr | may | jun | jul | aug | sep | oct | nov | dec | Year |
Wind speed, m/s
| jan | feb | mar | apr | may | jun | jul | aug | sep | oct | nov | dec | Year |
The frequency of different wind directions, %
| direction | jan | feb | mar | apr | may | jun | jul | aug | sep | oct | nov | dec | Year |
Air humidity, %
| jan | feb | mar | apr | may | jun | jul | aug | sep | oct | nov | dec | Year |
Snow cover
| Month | jul | aug | sep | oct | nov | dec | jan | feb | mar | apr | may | jun | Year |
| number of days | |||||||||||||
| height (sm) | |||||||||||||
| max height (sm) |
Cloudy, score
| month | jan | feb | mar | apr | may | jun | jul | aug | sep | oct | nov | dec | Year |
| total | |||||||||||||
| low |
Number of clear, cloudy and cloudy days
| month | jan | feb | mar | apr | may | jun | jul | aug | sep | oct | nov | dec | Year |
| Total cloud | |||||||||||||
| Low cloud | |||||||||||||
Number of days with different phenomena
| phenomenon | jan | feb | mar | apr | may | jun | jul | aug | sep | oct | nov | dec | Year |
The frequency of different types of clouds, %
| type of clouds | jan | feb | mar | apr | may | jun | jul | aug | sep | oct | nov | dec | Year |