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Winnetka climate
Typical historical weather for Winnetka, United States, averaged across 10 years of hourly climate data. Pick a date for a specific day.
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Annual average
10.7°C
across all months
Warmest month
26.6°C
Jul average high
Coolest month
-5.6°C
Jan average low
Annual rainfall
1032mm
total per year
Winnetka is typically hottest in July and coolest in January, a swing of about 32.2°C across the year. About 33% of annual rainfall falls in the three wettest months (May is typically wettest, February driest).
Monthly averages
Average daily high/low temperature (band) and monthly rainfall (bars).
| Month | Avg high | Avg low | Rainfall | Wet days | Humidity | Wind | Cloud | Solar |
|---|---|---|---|---|---|---|---|---|
| Jan | 0°C · record 4.4–13.1°C | -5.6°C · record -29.7–-12.2°C | 70mm | 11 | 74% | 4.8 m/s | 75% | 1.8 kWh/m² |
| Feb | 2.5°C · record 10.1–20.1°C | -4.6°C · record -20.1–-9.9°C | 59mm | 10 | 70% | 4.9 m/s | 66% | 2.9 kWh/m² |
| Mar | 7.6°C · record 12.2–22.4°C | 0.6°C · record -18.9–-2.8°C | 93mm | 13 | 69% | 4.7 m/s | 66% | 4 kWh/m² |
| Apr | 12°C · record 21.7–25.2°C | 4.5°C · record -6.2–1.6°C | 112mm | 13 | 68% | 4.6 m/s | 65% | 5.1 kWh/m² |
| May | 17.8°C · record 24.9–29.8°C | 10.2°C · record -0.8–7.4°C | 120mm | 13 | 72% | 4 m/s | 62% | 6 kWh/m² |
| Jun | 24.5°C · record 28–33.4°C | 16.6°C · record 6.2–11.8°C | 103mm | 11 | 71% | 3.7 m/s | 54% | 6.7 kWh/m² |
| Jul | 26.6°C · record 29.8–33.1°C | 19.7°C · record 12.9–17.7°C | 95mm | 12 | 75% | 3.1 m/s | 53% | 6.5 kWh/m² |
| Aug | 26.2°C · record 27.9–35.4°C | 19.2°C · record 12–15.6°C | 81mm | 11 | 74% | 3.2 m/s | 50% | 5.8 kWh/m² |
| Sep | 23.6°C · record 28.8–32.7°C | 16.1°C · record 6.3–13.3°C | 70mm | 10 | 73% | 3.8 m/s | 49% | 4.6 kWh/m² |
| Oct | 16.8°C · record 24.1–29.7°C | 9.5°C · record -0.7–5.3°C | 108mm | 12 | 71% | 4.6 m/s | 56% | 3.1 kWh/m² |
| Nov | 9°C · record 11.2–22.7°C | 2.4°C · record -12–-2.3°C | 61mm | 8 | 70% | 4.9 m/s | 62% | 2.1 kWh/m² |
| Dec | 3.3°C · record 10.7–17.9°C | -2.5°C · record -21.8–-6.6°C | 63mm | 10 | 73% | 4.8 m/s | 72% | 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.
Across these 10 years, the annual average has moved by about +0.81°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 -268.64mm per decade over the same period.
2025 (the most recent year on file) averaged 10.516540255611911°C, below the 9-year baseline of 10.74°C by 0.31 standard deviations.
Typical extremes per year
Rainy days
130.6 days
≥1.0mm rain
Heavy rain days
10.4 days
≥20mm rain
Extreme heat days
0 days
daily high ≥40°C
Frost days
93.7 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
35.4°C
24 August 2023
2023 was 0.94 SD above the 9-year average that year
Coldest day
-29.7°C
31 January 2019
2019 was 2.38 SD below the 9-year average that year
Wettest day
78.7mm
25 June 2021
2021 was 1.09 SD above the 9-year average that year
Windiest day
10.9m/s
26 November 2025
2025 was 0.31 SD below the 9-year average that year
See the detail: Winnetka on 25 June 2021.
Nearby cities
West Town
Same ERA5 grid cell
Near North Side
Same ERA5 grid cell
Belmont Cragin
Same ERA5 grid cell
Evanston
Same ERA5 grid cell
Logan Square
Same ERA5 grid cell
West Ridge
Same ERA5 grid cell
Want a side-by-side view instead? Compare Winnetka with another city.
Frequently asked questions about Winnetka's climate
What is the hottest month in Winnetka?
July is typically the warmest month in Winnetka, with an average high of 26.6°C. January is typically the coolest, averaging -5.6°C overnight.
How much does it rain in Winnetka?
Winnetka gets about 1032mm of rain a year on average, with roughly 33% of it falling in the three wettest months (May is typically the wettest, February the driest).
How many extremely hot or cold days does Winnetka have?
On average, Winnetka sees about 0 day(s) a year at or above 40°C and about 93.7 day(s) at or below 0°C, based on 10 years of data.
Is Winnetka getting warmer?
Across the 10 years on file (2016–2025), the annual average temperature has moved by about +0.81°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 Winnetka?
The hottest day on file is 24 August 2023 at 35.4°C, out of 10 year(s) searched.
Data & provenance
↓ Download monthly CSVData 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
- Winnetka — 42.000°, -87.750°, ERA5 grid cell center, 12.1 km from requested point
- Time zone
- America/Chicago
- 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
PastClimate (2026-07-18). Historical climate data for Winnetka, United States (42.00°N, 87.75°W), derived from ERA5 (Hersbach et al., 2023, Copernicus Climate Change Service). Retrieved from https://www.pastclimate.com/
PastClimate. (2026). Historical climate data for Winnetka, United States [Data set]. Derived from ERA5 (Copernicus Climate Change Service). Retrieved July 18, 2026, from https://www.pastclimate.com/
"Historical Climate Data for Winnetka, United States." PastClimate, derived from ERA5 (Copernicus Climate Change Service), July 18, 2026, www.pastclimate.com.
@misc{pastclimate,
author = {PastClimate},
title = {Historical climate data for Winnetka, United States},
year = {2026},
note = {Derived from ERA5 (Hersbach et al., 2023), Copernicus Climate Change Service. Accessed 2026-07-18},
url = {https://www.pastclimate.com/}
}Notice something wrong with this data? Report a data issue.