Willoughby climate
Typical historical weather for Willoughby, Australia, averaged across 10 years of hourly climate data. Pick a date for a specific day.
Want today's actual conditions instead? See the current forecast for Willoughby. Planning a garden? See the gardening & growing season planner. Or browse the 365-day climate calendar.
Annual average
18.5°C
across all months
Warmest month
24.7°C
Jan average high
Coolest month
11.3°C
Jul average low
Annual rainfall
1078mm
total per year
Willoughby is typically hottest in January and coolest in July, a swing of about 13.4°C across the year. About 35% of annual rainfall falls in the three wettest months (March is typically wettest, September 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 | 24.7°C · record 26.3–34.9°C | 20.9°C · record 16.2–19.9°C | 93mm | 13 | 78% | 5 m/s | 58% | 6.1 kWh/m² |
| Feb | 24.7°C · record 26.6–32.3°C | 20.8°C · record 16.2–19.6°C | 112mm | 14 | 76% | 5 m/s | 52% | 5.7 kWh/m² |
| Mar | 23.8°C · record 25.1–33.1°C | 20°C · record 13.8–17.8°C | 166mm | 18 | 77% | 4.9 m/s | 57% | 4.5 kWh/m² |
| Apr | 21.9°C · record 24.2–30.1°C | 17.2°C · record 12.3–15.9°C | 84mm | 13 | 74% | 4.3 m/s | 44% | 3.9 kWh/m² |
| May | 19.2°C · record 21.2–24.5°C | 14.1°C · record 7.8–12.1°C | 86mm | 11 | 71% | 4.6 m/s | 42% | 3 kWh/m² |
| Jun | 16.8°C · record 18.3–22.2°C | 11.9°C · record 7.8–9.6°C | 95mm | 12 | 72% | 5.1 m/s | 44% | 2.5 kWh/m² |
| Jul | 16.8°C · record 19.5–23.2°C | 11.3°C · record 6.3–9.2°C | 93mm | 9 | 68% | 5.1 m/s | 36% | 2.8 kWh/m² |
| Aug | 17.4°C · record 20.8–25.8°C | 11.7°C · record 7.6–9.3°C | 78mm | 9 | 68% | 4.9 m/s | 38% | 3.7 kWh/m² |
| Sep | 19.3°C · record 21.2–28.6°C | 13.4°C · record 9.1–10.8°C | 57mm | 9 | 67% | 5 m/s | 37% | 4.9 kWh/m² |
| Oct | 20.7°C · record 23.1–32.4°C | 15.6°C · record 10.7–13.6°C | 78mm | 11 | 71% | 4.9 m/s | 50% | 5.6 kWh/m² |
| Nov | 21.9°C · record 23.4–34.3°C | 17.3°C · record 11.7–16.5°C | 68mm | 10 | 72% | 4.9 m/s | 51% | 6.5 kWh/m² |
| Dec | 23.6°C · record 25.7–31.8°C | 19.2°C · record 14.2–17.8°C | 69mm | 10 | 75% | 4.8 m/s | 52% | 6.7 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 -0.13°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 +359.23mm per decade over the same period.
2025 (the most recent year on file) averaged 18.739742024739606°C, above the 9-year baseline of 18.4°C by 1.04 standard deviations.
Typical extremes per year
Rainy days
135.8 days
≥1.0mm rain
Heavy rain days
10.7 days
≥20mm rain
Extreme heat days
0 days
daily high ≥40°C
Frost days
0 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
34.9°C
31 January 2017
2017 was 0.8 SD above the 9-year average that year
Coldest day
6.3°C
16 July 2018
2018 was 0.18 SD below the 9-year average that year
Wettest day
134.2mm
9 February 2020
2020 was 0.71 SD below the 9-year average that year
Windiest day
14.1m/s
17 January 2025
2025 was 1.04 SD above the 9-year average that year
See the detail: Willoughby on 9 February 2020.
Nearby cities
Sydney
Same ERA5 grid cell
Pittwater
Same ERA5 grid cell
Mosman
Same ERA5 grid cell
Sydney Central Business District
Same ERA5 grid cell
Chatswood
Same ERA5 grid cell
Dee Why
Same ERA5 grid cell
Want a side-by-side view instead? Compare Willoughby with another city.
Frequently asked questions about Willoughby's climate
What is the hottest month in Willoughby?
January is typically the warmest month in Willoughby, with an average high of 24.7°C. July is typically the coolest, averaging 11.3°C overnight.
How much does it rain in Willoughby?
Willoughby gets about 1078mm of rain a year on average, with roughly 35% of it falling in the three wettest months (March is typically the wettest, September the driest).
How many extremely hot or cold days does Willoughby have?
On average, Willoughby sees about 0 day(s) a year at or above 40°C and about 0 day(s) at or below 0°C, based on 10 years of data.
Is Willoughby 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 Willoughby?
The hottest day on file is 31 January 2017 at 34.9°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 Australia
- Location
- Willoughby — -33.750°, 151.250°, ERA5 grid cell center, 7.7 km from requested point
- Time zone
- Australia/Sydney
- 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 Willoughby, Australia (-33.75°S, 151.25°E), derived from ERA5 (Hersbach et al., 2023, Copernicus Climate Change Service). Retrieved from https://www.pastclimate.com/
PastClimate. (2026). Historical climate data for Willoughby, Australia [Data set]. Derived from ERA5 (Copernicus Climate Change Service). Retrieved July 18, 2026, from https://www.pastclimate.com/
"Historical Climate Data for Willoughby, Australia." PastClimate, derived from ERA5 (Copernicus Climate Change Service), July 18, 2026, www.pastclimate.com.
@misc{pastclimate,
author = {PastClimate},
title = {Historical climate data for Willoughby, Australia},
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.