Home / Altadena / 28 December 2016

Altadena

United States · 28 December 2016

AltadenaUnited States4:25 PM localChange location

← 27 December 201629 December 2016 →

Average

11.4°C

low 5.7° · high 20.5°

Rainfall

0mm

dry day

Wind

3.3m/s

daily average

Humidity

46.2%

daily average

Cloud

0%

cover

Pressure

1021hPa

daily average

The temperature ranged from 5.7°C around 06:00 to 20.5°C around 13:00. No measurable rain was recorded during the day.

How unusual was this day?

Compared against the same 135 calendar days (±7 days) across the other 9 years on file.

High temperature

84th percentile

Low temperature

28th percentile

Rainfall

61th percentile

Wind

97th 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 11.2°C, versus 11.4°C on this specific day.

Sun & daylight

Sunrise

06:58

Sunset

16:51

Day length

9h 53m

Hour by hour

Temperature (line) and hourly rainfall (bars), local time — America/Los_Angeles.

↓ Download CSV
00:0006:0012:0018:0023:00

Cumulative rainfall through the day.

00:0006:0012:0018:0023:00
Local timeUTCTemp °CFeels °CRain mmWind m/sDirHumidity %Pressure hPa
00:0008:006.82.303.6NNE621022
01:0009:005.91.303.7NNE641021
02:0010:0061.403.6NNE601021
03:0011:0061.203.7NNE621021
04:0012:005.81.103.7NNE591021
05:0013:0061.203.7NNE581021
06:0014:005.70.903.8NNE601021
07:0015:005.80.903.8NNE591021
08:0016:006.9203.9NNE541022
09:0017:0011.97.203.6NNE411022
10:0018:0015.41103NNE301022
11:0019:0017.513.102.9NNE251022
12:0020:0019.114.802.9NNE241021
13:0021:0020.51602.9NNE201020
14:0022:0020.316.402.3NNE201019
15:0023:0019.515.502.3NNE211019
16:0000:001814.302NNE251019
17:0001:0014.611.202.2NNE381020
18:0002:0012.8902.9NNE461020
19:0003:0011.37.503.2NNE561021
20:0004:009.75.503.5NNE571021
21:0005:009.85.603.6NNE581022
22:0006:009.75.303.7NNE561022
23:0007:0094.503.7NNE561022

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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
Altadena — 34.250°, -118.250°, ERA5 grid cell center, 12.8 km from requested point
Time zone
America/Los_Angeles
What's shown here
The hourly and daily record for 28 December 2016 specifically — not a monthly average. See the Altadena 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

Plain text
PastClimate (2026-07-17). Historical climate data for Altadena, United States (34.25°N, 118.25°W), derived from ERA5 (Hersbach et al., 2023, Copernicus Climate Change Service). Retrieved from https://www.pastclimate.com/
APA
PastClimate. (2026). Historical climate data for Altadena, United States [Data set]. Derived from ERA5 (Copernicus Climate Change Service). Retrieved July 17, 2026, from https://www.pastclimate.com/
MLA
"Historical Climate Data for Altadena, United States." PastClimate, derived from ERA5 (Copernicus Climate Change Service), July 17, 2026, www.pastclimate.com.
BibTeX
@misc{pastclimate,
  author = {PastClimate},
  title = {Historical climate data for Altadena, 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/}
}

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