Jamestown climate — normals and trends
Jamestown (United States) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 4.9 °C and it receives 604 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 (20.9 °C on average) and the coldest is January (-13.0 °C). Rainfall peaks in June.
Jamestown averages 172 frost days, 16 hot days (≥ 30 °C) and 89 rainy days per year.
Jamestown has warmed by +1.4 °C between 1940 and 2025, or +0.16 °C per decade. This trend is statistically significant.
The hottest day of the period reached 39.3 °C (on 5 July 1989) and the coldest -38.9 °C (on 24 January 1966).
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
JamestownNorth Dakota
- coords
- 46.91°, -98.71°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
4.9°C
Average daily high
10.1°C
Average daily low
-0.1°C
Annual rainfall
604mm
Sunshine / day
9.1h
Mean relative humidity
72%
Average peak wind
23.4km/h
Seasonal range
33.9°C
Frost days (< 0 °C)
172 d/yr
Hot days (≥ 30 °C)
16 d/yr
Rainy days (≥ 1 mm)
89 d/yr
Annual snowfall
86.4 cm
Average feels-like high
6.7 °C
Average feels-like low
-4.2 °C
Average peak gust
40.5 km/h
Tropical nights (≥ 20 °C)
4 d/yr
Solar radiation
14.6 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.4 °C
since 1940
+0.2 °C per decade · r² = 0.12 · 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
39.3 °C
5 July 1989
Coldest day
-38.9 °C
24 January 1966
Wettest day
103 mm
17 June 2010
Windiest day
82.4 km/h
4 March 1966
Strongest gust
113.4 km/h
19 February 1948
Hottest feels-like
42.4 °C
15 July 2006
Coldest feels-like
-44.9 °C
2 February 1996
Snowiest day
24.7 cm
5 December 1960
Sunniest day
15.1 h
2 July 2025
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | -8.0 °C | +0.7 °C | 12 mm | -7 mm |
| Feb | -9.2 °C | -3.1 °C | 11 mm | -6 mm |
| Mar | 6.5 °C | +5.8 °C | 11 mm | -20 mm |
| Apr | 11.7 °C | +1.2 °C | 92 mm | +38 mm |
| May | 20.7 °C | +2.3 °C | 81 mm | +1 mm |
| Jun | 23.4 °C | 0.0 °C | 70 mm | -29 mm |
| Jul | 26.1 °C | -0.4 °C | 119 mm | +35 mm |
| Aug | 25.2 °C | -0.6 °C | 68 mm | -4 mm |
| Sep | 23.3 °C | +2.9 °C | 44 mm | -13 mm |
| Oct | 15.3 °C | +2.3 °C | 67 mm | +22 mm |
| Nov | 5.2 °C | +2.9 °C | 23 mm | -2 mm |
| Dec | -3.8 °C | +1.7 °C | 26 mm | +5 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 Jamestown?
Jamestown has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 4.9 °C and it receives 604 mm of precipitation per year.
What is the hottest day ever recorded in Jamestown?
The hottest day measured in Jamestown between 1940 and 2025 was 5 July 1989, reaching 39.3 °C.
What is the coldest day in Jamestown?
The coldest day measured in Jamestown between 1940 and 2025 was 24 January 1966, at -38.9 °C.
Does it snow in Jamestown?
Yes. Jamestown gets on average 86.4 cm of snow per year and has around 172 frost days.
Has the climate of Jamestown warmed?
Yes: Jamestown warmed by +1.4 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Jamestown?
The wettest day measured in Jamestown between 1940 and 2025 was 17 June 2010, with 103 mm of rain in 24 hours.
What was the windiest day in Jamestown?
The windiest day measured in Jamestown between 1940 and 2025 was 4 March 1966, with winds reaching 82.4 km/h.
What is the warmest month in Jamestown?
The warmest month in Jamestown is July (20.9 °C on average); the coldest is January (-13.0 °C).
How much does it rain in Jamestown?
Jamestown receives on average 604 mm of precipitation per year, spread over about 89 rainy days.
Is it sunny in Jamestown?
Jamestown gets on average 9.1 hours of sunshine per day, roughly 3,322 hours per year over 1940-2025.
What is the biggest single-day snowfall in Jamestown?
The heaviest 24-hour snowfall measured in Jamestown between 1940 and 2025 was 5 December 1960, with 24.7 cm.
Are there tropical nights in Jamestown?
Yes: Jamestown has on average 4 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Jamestown?
In Jamestown, between 1940 and 2025, the highest apparent temperature reached 42.4 °C on 15 July 2006, and the lowest was -44.9 °C on 2 February 1996.
Compare Jamestown with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Jamestown