Suffolk climate — normals and trends
Suffolk (United States) has a humid subtropical climate (Cfa) under the Köppen-Geiger classification. Its mean annual temperature is 15.5 °C and it receives 1,150 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 (25.9 °C on average) and the coldest is January (4.8 °C). Rainfall peaks in July.
Suffolk averages 46 frost days, 59 hot days (≥ 30 °C) and 126 rainy days per year.
Suffolk has warmed by +1.1 °C between 1940 and 2025, or +0.13 °C per decade. This trend is statistically significant.
The hottest day of the period reached 40.1 °C (on 23 July 2011) and the coldest -21.6 °C (on 30 January 2014).
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
SuffolkVirginia
- coords
- 36.73°, -76.58°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
15.5°C
Average daily high
20.6°C
Average daily low
11.0°C
Annual rainfall
1,150mm
Sunshine / day
9.2h
Mean relative humidity
71%
Average peak wind
17.4km/h
Seasonal range
21.1°C
Frost days (< 0 °C)
46 d/yr
Hot days (≥ 30 °C)
59 d/yr
Rainy days (≥ 1 mm)
126 d/yr
Annual snowfall
16.1 cm
Average feels-like high
20.3 °C
Average feels-like low
9.5 °C
Average peak gust
38.1 km/h
Tropical nights (≥ 20 °C)
76 d/yr
Solar radiation
15.7 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.1 °C
since 1940
+0.1 °C per decade · r² = 0.23 · 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
40.1 °C
23 July 2011
Coldest day
-21.6 °C
30 January 2014
Wettest day
185 mm
27 August 2011
Windiest day
67.5 km/h
18 September 2003
Strongest gust
151.9 km/h
18 September 2003
Hottest feels-like
44.6 °C
1 August 1999
Coldest feels-like
-27.5 °C
21 January 1985
Snowiest day
28.2 cm
26 January 1966
Sunniest day
14.0 h
15 May 1940
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 | 7.5 °C | -2.0 °C | 49 mm | -40 mm |
| Feb | 11.9 °C | +0.8 °C | 124 mm | +38 mm |
| Mar | 19.2 °C | +4.0 °C | 61 mm | -35 mm |
| Apr | 23.6 °C | +3.0 °C | 102 mm | +18 mm |
| May | 25.6 °C | +0.8 °C | 135 mm | +39 mm |
| Jun | 31.1 °C | +2.3 °C | 117 mm | +20 mm |
| Jul | 32.2 °C | +1.5 °C | 134 mm | +5 mm |
| Aug | 27.7 °C | -2.0 °C | 98 mm | -27 mm |
| Sep | 26.2 °C | -0.6 °C | 118 mm | +10 mm |
| Oct | 20.8 °C | -0.9 °C | 78 mm | -0 mm |
| Nov | 17.3 °C | +0.9 °C | 54 mm | -27 mm |
| Dec | 9.9 °C | -1.6 °C | 98 mm | +17 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 Suffolk?
Suffolk has a humid subtropical climate (Köppen Cfa). Over 1940-2025, the average annual temperature is 15.5 °C and it receives 1,150 mm of precipitation per year.
What is the hottest day ever recorded in Suffolk?
The hottest day measured in Suffolk between 1940 and 2025 was 23 July 2011, reaching 40.1 °C.
What is the coldest day in Suffolk?
The coldest day measured in Suffolk between 1940 and 2025 was 30 January 2014, at -21.6 °C.
Does it snow in Suffolk?
Yes. Suffolk gets on average 16.1 cm of snow per year and has around 46 frost days.
Has the climate of Suffolk warmed?
Yes: Suffolk warmed by +1.1 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Suffolk?
The wettest day measured in Suffolk between 1940 and 2025 was 27 August 2011, with 185 mm of rain in 24 hours.
What was the windiest day in Suffolk?
The windiest day measured in Suffolk between 1940 and 2025 was 18 September 2003, with winds reaching 67.5 km/h.
What is the warmest month in Suffolk?
The warmest month in Suffolk is July (25.9 °C on average); the coldest is January (4.8 °C).
How much does it rain in Suffolk?
Suffolk receives on average 1,150 mm of precipitation per year, spread over about 126 rainy days.
Is it sunny in Suffolk?
Suffolk gets on average 9.2 hours of sunshine per day, roughly 3,358 hours per year over 1940-2025.
What is the biggest single-day snowfall in Suffolk?
The heaviest 24-hour snowfall measured in Suffolk between 1940 and 2025 was 26 January 1966, with 28.2 cm.
Are there tropical nights in Suffolk?
Yes: Suffolk has on average 76 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Suffolk?
In Suffolk, between 1940 and 2025, the highest apparent temperature reached 44.6 °C on 1 August 1999, and the lowest was -27.5 °C on 21 January 1985.
Compare Suffolk with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Suffolk