Home / Walnut Creek / 23 October 2021
Walnut Creek
United States · 23 October 2021
← 22 October 202124 October 2021 →
Average
15.4°C
low 12.8° · high 18.4°
Rainfall
1.8mm
rain recorded
Wind
2.1m/s
daily average
Humidity
76.6%
daily average
Cloud
87%
cover
Pressure
1013hPa
daily average
The temperature ranged from 12.8°C around 07:00 to 18.4°C around 15:00. Rain was recorded across 4 hours, from around 20:00 to 23:00 (1.8mm total).
How unusual was this day?
Compared against the same 135 calendar days (±7 days) across the other 9 years on file.
High temperature
1th percentile
Low temperature
76th percentile
Rainfall
93th percentile
Wind
56th percentile
A percentile of 100 means this was the hottest/wettest/windiest of the comparable days on file; 50 is right in the middle. This window's average temperature was 16.7°C, versus 15.4°C on this specific day.
Sun & daylight
Sunrise
07:24
Sunset
18:19
Day length
10h 54m
Hour by hour
Temperature (line) and hourly rainfall (bars), local time — America/Los_Angeles.
Cumulative rainfall through the day.
| Local time | UTC | Temp °C | Feels °C | Rain mm | Wind m/s | Dir | Humidity % | Pressure hPa |
|---|---|---|---|---|---|---|---|---|
| 00:00 | 07:00 | 13.4 | 12.2 | 0 | 2.5 | WSW | 88 | 1015 |
| 01:00 | 08:00 | 13 | 11.8 | 0 | 2.3 | WSW | 89 | 1015 |
| 02:00 | 09:00 | 13.4 | 12.4 | 0 | 2.2 | SW | 89 | 1015 |
| 03:00 | 10:00 | 13.6 | 12.9 | 0 | 1.5 | SW | 85 | 1015 |
| 04:00 | 11:00 | 12.8 | 12 | 0 | 1.6 | SW | 89 | 1015 |
| 05:00 | 12:00 | 12.9 | 12.1 | 0 | 1.6 | SW | 89 | 1015 |
| 06:00 | 13:00 | 12.9 | 11.9 | 0 | 1.8 | SW | 88 | 1015 |
| 07:00 | 14:00 | 12.8 | 11.8 | 0 | 1.8 | SW | 89 | 1014 |
| 08:00 | 15:00 | 12.9 | 11.8 | 0 | 2 | SW | 88 | 1014 |
| 09:00 | 16:00 | 13.9 | 12.6 | 0 | 2.4 | SW | 83 | 1015 |
| 10:00 | 17:00 | 15 | 13.7 | 0 | 2.5 | SW | 80 | 1015 |
| 11:00 | 18:00 | 16.2 | 14.8 | 0 | 2.6 | SSW | 71 | 1015 |
| 12:00 | 19:00 | 17.1 | 15.2 | 0 | 3.1 | SW | 67 | 1015 |
| 13:00 | 20:00 | 17.4 | 15.4 | 0 | 3.1 | SW | 65 | 1014 |
| 14:00 | 21:00 | 17.8 | 15.5 | 0 | 3.4 | SW | 62 | 1014 |
| 15:00 | 22:00 | 18.4 | 16.4 | 0 | 2.8 | SW | 57 | 1013 |
| 16:00 | 23:00 | 17.9 | 16.6 | 0 | 2 | SW | 61 | 1013 |
| 17:00 | 00:00 | 17.7 | 16.9 | 0 | 1.3 | SW | 62 | 1012 |
| 18:00 | 01:00 | 17.5 | 16.8 | 0 | 1.4 | S | 64 | 1011 |
| 19:00 | 02:00 | 17.4 | 16.8 | 0 | 1.2 | SSE | 66 | 1012 |
| 20:00 | 03:00 | 16.8 | 16.2 | 0.37 | 1.6 | SSE | 71 | 1011 |
| 21:00 | 04:00 | 16.2 | 15.5 | 1.05 | 1.9 | SSE | 76 | 1011 |
| 22:00 | 05:00 | 16 | 15.3 | 0.24 | 1.9 | SSE | 78 | 1010 |
| 23:00 | 06:00 | 15.6 | 14.8 | 0.12 | 2.3 | SSE | 83 | 1010 |
Nearby cities
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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
- Walnut Creek — 38.000°, -122.000°, ERA5 grid cell center, 11.9 km from requested point
- Time zone
- America/Los_Angeles
- What's shown here
- The hourly and daily record for 23 October 2021 specifically — not a monthly average. See the Walnut Creek climate overview for typical conditions.
- 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 (2026-07-16). Historical climate data for Walnut Creek, United States (38.00°N, 122.00°W), derived from ERA5 (Hersbach et al., 2023, Copernicus Climate Change Service). Retrieved from https://www.pastclimate.com/
PastClimate. (2026). Historical climate data for Walnut Creek, United States [Data set]. Derived from ERA5 (Copernicus Climate Change Service). Retrieved July 16, 2026, from https://www.pastclimate.com/
"Historical Climate Data for Walnut Creek, United States." PastClimate, derived from ERA5 (Copernicus Climate Change Service), July 16, 2026, www.pastclimate.com.
@misc{pastclimate,
author = {PastClimate},
title = {Historical climate data for Walnut Creek, United States},
year = {2026},
note = {Derived from ERA5 (Hersbach et al., 2023), Copernicus Climate Change Service. Accessed 2026-07-16},
url = {https://www.pastclimate.com/}
}Notice something wrong with this data? Report a data issue.