Home / Walla Walla / 20 May 2018
Walla Walla
United States · 20 May 2018
Average
15.4°C
low 10.5° · high 19.4°
Rainfall
2.3mm
rain recorded
Wind
1.7m/s
daily average
Humidity
70.4%
daily average
Cloud
80%
cover
Pressure
1011hPa
daily average
The temperature ranged from 10.5°C around 03:00 to 19.4°C around 14:00. Rain was recorded across 7 hours, from around 09:00 to 15:00 (2.3mm total).
How unusual was this day?
Compared against the same 135 calendar days (±7 days) across the other 9 years on file.
High temperature
59th percentile
Low temperature
83th percentile
Rainfall
81th percentile
Wind
15th 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 13.5°C, versus 15.4°C on this specific day.
Sun & daylight
Sunrise
05:15
Sunset
20:24
Day length
15h 9m
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 | 14.4 | 13.8 | 0 | 1.1 | ESE | 78 | 1011 |
| 01:00 | 08:00 | 14 | 13.3 | 0 | 1.2 | ESE | 80 | 1011 |
| 02:00 | 09:00 | 13.2 | 12.3 | 0 | 1.3 | ESE | 80 | 1011 |
| 03:00 | 10:00 | 10.5 | 9.2 | 0 | 1.5 | SE | 89 | 1011 |
| 04:00 | 11:00 | 11 | 9.9 | 0 | 1.3 | SE | 88 | 1011 |
| 05:00 | 12:00 | 11.3 | 10.2 | 0 | 1.3 | SE | 85 | 1011 |
| 06:00 | 13:00 | 11.9 | 10.7 | 0 | 1.2 | SE | 80 | 1012 |
| 07:00 | 14:00 | 13.1 | 11.8 | 0 | 1.1 | SSE | 70 | 1012 |
| 08:00 | 15:00 | 15.2 | 13.7 | 0.07 | 1.1 | WSW | 57 | 1012 |
| 09:00 | 16:00 | 14.9 | 13.5 | 0.21 | 1.2 | WSW | 63 | 1013 |
| 10:00 | 17:00 | 14.6 | 13.3 | 0.47 | 1.6 | W | 69 | 1013 |
| 11:00 | 18:00 | 15.3 | 14 | 0.44 | 1.8 | W | 70 | 1012 |
| 12:00 | 19:00 | 16 | 14.8 | 0.26 | 2.1 | W | 72 | 1012 |
| 13:00 | 20:00 | 18.1 | 16.7 | 0.18 | 2.8 | WNW | 67 | 1011 |
| 14:00 | 21:00 | 19.4 | 18 | 0.46 | 2.6 | WNW | 59 | 1012 |
| 15:00 | 22:00 | 19 | 17.6 | 0.24 | 2.4 | W | 58 | 1011 |
| 16:00 | 23:00 | 18.7 | 17.1 | 0.01 | 2.5 | WNW | 59 | 1011 |
| 17:00 | 00:00 | 18.7 | 17.4 | 0 | 2.1 | WNW | 59 | 1011 |
| 18:00 | 01:00 | 19.3 | 18.4 | 0 | 1.5 | W | 56 | 1011 |
| 19:00 | 02:00 | 18.7 | 18 | 0 | 1.3 | WSW | 58 | 1011 |
| 20:00 | 03:00 | 17 | 16.1 | 0 | 1.7 | SW | 67 | 1010 |
| 21:00 | 04:00 | 15.2 | 14.1 | 0 | 1.9 | SSW | 74 | 1011 |
| 22:00 | 05:00 | 15.2 | 14.2 | 0 | 1.9 | SSW | 76 | 1012 |
| 23:00 | 06:00 | 14.2 | 13 | 0 | 2 | SSW | 78 | 1012 |
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
- Walla Walla — 46.000°, -118.250°, ERA5 grid cell center, 10.2 km from requested point
- Time zone
- America/Los_Angeles
- What's shown here
- The hourly and daily record for 20 May 2018 specifically — not a monthly average. See the Walla Walla 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 (2026-07-17). Historical climate data for Walla Walla, United States (46.00°N, 118.25°W), derived from ERA5 (Hersbach et al., 2023, Copernicus Climate Change Service). Retrieved from https://www.pastclimate.com/
PastClimate. (2026). Historical climate data for Walla Walla, United States [Data set]. Derived from ERA5 (Copernicus Climate Change Service). Retrieved July 17, 2026, from https://www.pastclimate.com/
"Historical Climate Data for Walla Walla, United States." PastClimate, derived from ERA5 (Copernicus Climate Change Service), July 17, 2026, www.pastclimate.com.
@misc{pastclimate,
author = {PastClimate},
title = {Historical climate data for Walla Walla, 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/}
}Notice something wrong with this data? Report a data issue.