Lewiston climate — normals and trends
Lewiston (United States) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 7.7 °C and it receives 1,073 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (20.8 °C on average) and the coldest is January (-6.2 °C). Rainfall peaks in November.
Lewiston averages 129 frost days, 5 hot days (≥ 30 °C) and 119 rainy days per year.
Lewiston has warmed by +1.6 °C between 1940 and 2025, or +0.18 °C per decade. This trend is statistically significant.
The number of frost days there went from about 136 to 122 per year over the period.
The hottest day of the period reached 36.1 °C (on 2 August 1975) and the coldest -29.1 °C (on 26 December 1980).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
LewistonMaine
- coords
- 44.10°, -70.21°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
7.7°C
Average daily high
11.9°C
Average daily low
3.5°C
Annual rainfall
1,073mm
Sunshine / day
8.6h
Mean relative humidity
73%
Average peak wind
16.4km/h
Seasonal range
27.0°C
Frost days (< 0 °C)
129 d/yr
Hot days (≥ 30 °C)
5 d/yr
Rainy days (≥ 1 mm)
119 d/yr
Annual snowfall
147.7 cm
Average feels-like high
9.9 °C
Average feels-like low
0.5 °C
Average peak gust
37.7 km/h
Tropical nights (≥ 20 °C)
7 d/yr
Solar radiation
14.0 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.6 °C
since 1940
+0.2 °C per decade · r² = 0.36 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
36.1 °C
2 August 1975
Coldest day
-29.1 °C
26 December 1980
Wettest day
119 mm
11 September 1954
Windiest day
53.8 km/h
31 August 1954
Strongest gust
134.3 km/h
31 August 1954
Hottest feels-like
40.7 °C
2 August 1975
Coldest feels-like
-34.7 °C
13 February 1967
Snowiest day
36.3 cm
18 February 1952
Sunniest day
15.0 h
16 June 1940
Normals computed over complete calendar years 1940–2025.
A specific year
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Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | -1.8 °C | +0.1 °C | 37 mm | -47 mm |
| Feb | -1.5 °C | -1.0 °C | 76 mm | -2 mm |
| Mar | 6.0 °C | +1.9 °C | 113 mm | +17 mm |
| Apr | 11.8 °C | +1.3 °C | 121 mm | +28 mm |
| May | 16.2 °C | -0.5 °C | 116 mm | +30 mm |
| Jun | 22.8 °C | +0.9 °C | 54 mm | -36 mm |
| Jul | 26.6 °C | +1.4 °C | 45 mm | -39 mm |
| Aug | 25.7 °C | +1.2 °C | 19 mm | -62 mm |
| Sep | 22.2 °C | +2.0 °C | 67 mm | -17 mm |
| Oct | 15.9 °C | +1.8 °C | 89 mm | -7 mm |
| Nov | 7.2 °C | -0.3 °C | 61 mm | -43 mm |
| Dec | -0.3 °C | -1.3 °C | 96 mm | -3 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Lewiston?
Lewiston has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 7.7 °C and it receives 1,073 mm of precipitation per year.
What is the hottest day ever recorded in Lewiston?
The hottest day measured in Lewiston between 1940 and 2025 was 2 August 1975, reaching 36.1 °C.
What is the coldest day in Lewiston?
The coldest day measured in Lewiston between 1940 and 2025 was 26 December 1980, at -29.1 °C.
Does it snow in Lewiston?
Yes. Lewiston gets on average 147.7 cm of snow per year and has around 129 frost days.
Has the climate of Lewiston warmed?
Yes: Lewiston warmed by +1.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Lewiston?
The wettest day measured in Lewiston between 1940 and 2025 was 11 September 1954, with 119 mm of rain in 24 hours.
What was the windiest day in Lewiston?
The windiest day measured in Lewiston between 1940 and 2025 was 31 August 1954, with winds reaching 53.8 km/h.
What is the warmest month in Lewiston?
The warmest month in Lewiston is July (20.8 °C on average); the coldest is January (-6.2 °C).
How much does it rain in Lewiston?
Lewiston receives on average 1,073 mm of precipitation per year, spread over about 119 rainy days.
Is it sunny in Lewiston?
Lewiston gets on average 8.6 hours of sunshine per day, roughly 3,139 hours per year over 1940-2025.
What is the biggest single-day snowfall in Lewiston?
The heaviest 24-hour snowfall measured in Lewiston between 1940 and 2025 was 18 February 1952, with 36.3 cm.
Are there tropical nights in Lewiston?
Yes: Lewiston has on average 7 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Lewiston?
In Lewiston, between 1940 and 2025, the highest apparent temperature reached 40.7 °C on 2 August 1975, and the lowest was -34.7 °C on 13 February 1967.
Compare Lewiston with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Lewiston