Altamont
United States · 25 May 2018
Average
12.2°C
low 9.7° · high 15.1°
Rainfall
47.1mm
rain recorded
Wind
2.3m/s
daily average
Humidity
87.9%
daily average
Cloud
99%
cover
Pressure
1014hPa
daily average
The temperature ranged from 9.7°C around 23:00 to 15.1°C around 01:00. Rain was recorded across 24 hours, from around 00:00 to 23:00 (47.1mm total).
How unusual was this day?
Compared against the same 135 calendar days (±7 days) across the other 9 years on file.
High temperature
18th percentile
Low temperature
83th percentile
Rainfall
100th percentile
Wind
50th 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 12.2°C on this specific day.
Sun & daylight
Sunrise
05:37
Sunset
20:31
Day length
14h 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 | 14.9 | 14.6 | 1.37 | 1 | NW | 80 | 1014 |
| 01:00 | 08:00 | 15.1 | 15.4 | 1.83 | 0.4 | SW | 82 | 1015 |
| 02:00 | 09:00 | 13.6 | 13.4 | 2.02 | 1.2 | SW | 90 | 1015 |
| 03:00 | 10:00 | 12.9 | 12.4 | 2.95 | 1.4 | SSE | 91 | 1014 |
| 04:00 | 11:00 | 12.7 | 12 | 3.93 | 1.6 | SSW | 91 | 1014 |
| 05:00 | 12:00 | 12.6 | 12.3 | 4.52 | 1 | SSW | 91 | 1014 |
| 06:00 | 13:00 | 12.5 | 12.4 | 3.54 | 0.5 | NW | 90 | 1013 |
| 07:00 | 14:00 | 12 | 11.8 | 2.42 | 0.6 | WNW | 91 | 1013 |
| 08:00 | 15:00 | 12.6 | 12.2 | 1.28 | 0.9 | WSW | 88 | 1013 |
| 09:00 | 16:00 | 13.3 | 12.6 | 0.3 | 1.5 | W | 86 | 1013 |
| 10:00 | 17:00 | 13.2 | 11.7 | 0.21 | 2.1 | W | 80 | 1013 |
| 11:00 | 18:00 | 13.7 | 11.8 | 0.16 | 2.5 | W | 75 | 1013 |
| 12:00 | 19:00 | 13.7 | 11.3 | 0.78 | 2.9 | W | 72 | 1013 |
| 13:00 | 20:00 | 12.6 | 9.8 | 0.79 | 3.5 | W | 76 | 1013 |
| 14:00 | 21:00 | 12.8 | 10.3 | 2.93 | 2.9 | W | 71 | 1013 |
| 15:00 | 22:00 | 11.4 | 9.9 | 1.42 | 2.5 | W | 94 | 1014 |
| 16:00 | 23:00 | 11.1 | 9.1 | 2.14 | 3.1 | WSW | 95 | 1013 |
| 17:00 | 00:00 | 11 | 8.5 | 2.7 | 3.6 | W | 93 | 1013 |
| 18:00 | 01:00 | 10.9 | 7.7 | 2.85 | 4.7 | WNW | 95 | 1013 |
| 19:00 | 02:00 | 11.2 | 8.2 | 2.6 | 4.5 | WNW | 94 | 1014 |
| 20:00 | 03:00 | 10 | 7.3 | 2.13 | 3.9 | WNW | 98 | 1014 |
| 21:00 | 04:00 | 9.7 | 7.3 | 1.74 | 3.2 | WNW | 97 | 1015 |
| 22:00 | 05:00 | 9.9 | 7.9 | 1.48 | 2.7 | WNW | 96 | 1016 |
| 23:00 | 06:00 | 9.7 | 7.7 | 1 | 2.6 | WNW | 95 | 1016 |
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
- Altamont — 42.250°, -121.750°, ERA5 grid cell center, 4.9 km from requested point
- Time zone
- America/Los_Angeles
- What's shown here
- The hourly and daily record for 25 May 2018 specifically — not a monthly average. See the Altamont 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 Altamont, United States (42.25°N, 121.75°W), derived from ERA5 (Hersbach et al., 2023, Copernicus Climate Change Service). Retrieved from https://www.pastclimate.com/
PastClimate. (2026). Historical climate data for Altamont, United States [Data set]. Derived from ERA5 (Copernicus Climate Change Service). Retrieved July 16, 2026, from https://www.pastclimate.com/
"Historical Climate Data for Altamont, 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 Altamont, 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.