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Chester climate

Typical historical weather for Chester, United States, averaged across 10 years of hourly climate data. Pick a date for a specific day.

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ChesterUnited States3:56 PM localChange location

Annual average

10.2°C

across all months

Warmest month

29.1°C

Jul average high

Coolest month

-6.5°C

Jan average low

Annual rainfall

1124mm

total per year

Chester is typically hottest in July and coolest in January, a swing of about 35.6°C across the year. About 30% of annual rainfall falls in the three wettest months (December is typically wettest, September driest).

Monthly averages

Average daily high/low temperature (band) and monthly rainfall (bars).

JanFebMarAprMayJunJulAugSepOctNovDec
Avg high Avg low Rainfall
MonthAvg highAvg lowRainfallWet daysHumidityWindCloudSolar
Jan1.6°C · record 6–19.5°C-6.5°C · record -22.9–-8.7°C87mm1066%3.4 m/s58%1.9 kWh/m²
Feb3.7°C · record 8.6–22.6°C-6°C · record -26.1–-12.2°C79mm1065%3.3 m/s58%2.8 kWh/m²
Mar7.8°C · record 13.1–24°C-1.6°C · record -18.9–-4.9°C97mm1161%3.6 m/s59%3.9 kWh/m²
Apr13.5°C · record 16.9–30°C3.8°C · record -6.9–-1.3°C109mm1362%3.4 m/s64%4.7 kWh/m²
May20°C · record 26.6–34.2°C9.6°C · record -0.3–4.7°C90mm1165%2.9 m/s65%5.5 kWh/m²
Jun25.6°C · record 31.7–38.5°C14.7°C · record 4.1–9°C86mm1266%2.7 m/s59%5.9 kWh/m²
Jul29.1°C · record 31.5–37.3°C18.3°C · record 11.2–14.9°C108mm1268%2.5 m/s57%5.9 kWh/m²
Aug27.8°C · record 28.6–37.4°C17.1°C · record 9.1–13.6°C82mm1069%2.5 m/s55%5.3 kWh/m²
Sep23.6°C · record 28.9–34.8°C13.2°C · record 2.5–8.7°C75mm873%2.6 m/s55%4.1 kWh/m²
Oct17.1°C · record 24.4–29.7°C7.2°C · record -6.2–1.3°C106mm1074%2.9 m/s55%2.8 kWh/m²
Nov9.4°C · record 15.6–27°C0.2°C · record -14.9–-4.1°C84mm1068%3.3 m/s50%2.1 kWh/m²
Dec3.4°C · record 12.1–16.3°C-4.7°C · record -21.9–-9°C123mm1170%3.2 m/s57%1.6 kWh/m²

"Avg high"/"Avg low" is the mean daily high/low for that month, averaged across every year on file. The "record" figure alongside it is a different statistic — the single hottest (or coldest) hour ever recorded during that month across all years — so it can sit above or below the average and does not describe the average's year-to-year spread. A "wet day" is any day with at least 1.0mm of rain.

Year to year

Annual average temperature, 2016–2025.

20162018202020222024

Across these 10 years, the annual average has moved by about +0.13°C per decade. That’s a short window for a reliable long-term climate trend — treat it as indicative, not definitive.

Annual rainfall has moved by about +129.57mm per decade over the same period.

2025 (the most recent year on file) averaged 9.612950172598525°C, below the 9-year baseline of 10.36°C by 1.9 standard deviations.

Typical extremes per year

Rainy days

125.2 days

≥1.0mm rain

Heavy rain days

11.7 days

≥20mm rain

Extreme heat days

0 days

daily high ≥40°C

Frost days

116 days

daily low ≤0°C

Averaged across 10 years on file. Thresholds match PastClimate's data pipeline definitions — see data & sources.

Records on file

Ranked across 10 years of data currently on file (2016–2025).

Hottest day

38.5°C

24 June 2025

2025 was 1.9 SD below the 9-year average that year

Coldest day

-26.1°C

4 February 2023

2023 was 0.72 SD above the 9-year average that year

Wettest day

89.8mm

11 December 2024

2024 was 1.14 SD above the 9-year average that year

Windiest day

8.3m/s

7 March 2025

2025 was 1.9 SD below the 9-year average that year

See the detail: Chester on 11 December 2024.

Frequently asked questions about Chester's climate

What is the hottest month in Chester?

July is typically the warmest month in Chester, with an average high of 29.1°C. January is typically the coolest, averaging -6.5°C overnight.

How much does it rain in Chester?

Chester gets about 1124mm of rain a year on average, with roughly 30% of it falling in the three wettest months (December is typically the wettest, September the driest).

How many extremely hot or cold days does Chester have?

On average, Chester sees about 0 day(s) a year at or above 40°C and about 116 day(s) at or below 0°C, based on 10 years of data.

Is Chester getting warmer?

Across the 10 years on file (2016–2025), the annual average temperature has moved by about +0.13°C per decade. That's a short window for a reliable long-term climate trend — treat it as indicative, not definitive.

What is the hottest day on record for Chester?

The hottest day on file is 24 June 2025 at 38.5°C, out of 10 year(s) searched.

Data & provenance

↓ Download monthly CSV
Data source & coverage — ERA5 reanalysis, 2016–2025 (10 years)details
Source
ERA5 reanalysis, accessed via the Copernicus Climate Change Service (C3S) Climate Data Store
Data type
Reanalysis — a physically consistent reconstruction combining a forecast model with historical observations, not a live station reading or a forecast
Coverage
2016–2025 (10 years) for United States
Location
Chester — 43.000°, -71.250°, ERA5 grid cell center, 4.8 km from requested point
Time zone
America/New_York
What's shown here
Monthly and annual averages, and dated extreme-value records, derived from an hourly base record.
Spatial resolution
0.25° (~25 km) distributed grid — ERA5's native model resolution is finer; this is the publicly distributed regridded product
Version / refreshed
Methodology v2026.07 · data last refreshed December 31, 2025
Limitations
A model reconstruction, not a station observation — hyper-local extremes (a single storm cell, an urban heat pocket) can differ from a nearby gauge. See the full methodology.
Attribution
Generated using Copernicus Climate Change Service information

Cite this data

Plain text
PastClimate (2026-07-17). Historical climate data for Chester, United States (43.00°N, 71.25°W), derived from ERA5 (Hersbach et al., 2023, Copernicus Climate Change Service). Retrieved from https://www.pastclimate.com/
APA
PastClimate. (2026). Historical climate data for Chester, United States [Data set]. Derived from ERA5 (Copernicus Climate Change Service). Retrieved July 17, 2026, from https://www.pastclimate.com/
MLA
"Historical Climate Data for Chester, United States." PastClimate, derived from ERA5 (Copernicus Climate Change Service), July 17, 2026, www.pastclimate.com.
BibTeX
@misc{pastclimate,
  author = {PastClimate},
  title = {Historical climate data for Chester, United States},
  year = {2026},
  note = {Derived from ERA5 (Hersbach et al., 2023), Copernicus Climate Change Service. Accessed 2026-07-17},
  url = {https://www.pastclimate.com/}
}

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