Sunnyvale Weather in December
Average highs run from 60°F on December 1 to 53°F on December 31, and lows from 39°F to 34°F. Normal precipitation for the month is 3.45 in over about 8 wet days.
December day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
December at a glance
- Average high
- 56°F
- Average low
- 36°F
- Precipitation
- 3.45 in
- Snowfall
- 0.2 in
- Record high
- 87°FDec 3, 2005
- Record low
- -1°FDec 22, 1989
- Chance of a freeze
- 100%
- Daylight
- 10 h 09 min to 10 h 01 min
- Cloud cover
- 55%
- Humidity
- 77%
- Dew point
- 38°F
- Wind
- 10.3 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Dec 1 | 60°F | 39°F | 82°F 2012 | 21°F 1979 | 24% | 0% |
| Dec 2 | 60°F | 39°F | 82°F 2012 | 20°F 1985 | 24% | 0% |
| Dec 3 | 59°F | 39°F | 87°F 2005 | 22°F 2006 | 25% | 0% |
| Dec 4 | 59°F | 39°F | 81°F 1977 | 23°F 2006 | 25% | 0% |
| Dec 5 | 59°F | 38°F | 78°F 1977 | 20°F 2009 | 25% | 0% |
| Dec 6 | 58°F | 38°F | 80°F 1966 | 18°F 1972 | 25% | 0% |
| Dec 7 | 58°F | 38°F | 80°F 2007 | 21°F 2006 | 25% | 0% |
| Dec 8 | 58°F | 37°F | 80°F 1977 | 18°F 2005 | 25% | 0% |
| Dec 9 | 58°F | 37°F | 82°F 2020 | 15°F 2005 | 25% | 0% |
| Dec 10 | 57°F | 37°F | 83°F 2021 | 15°F 2005 | 25% | 0% |
| Dec 11 | 57°F | 37°F | 80°F 1996 | 19°F 1989 | 25% | 0% |
| Dec 12 | 57°F | 36°F | 80°F 1973 | 17°F 1989 | 26% | 0% |
| Dec 13 | 57°F | 36°F | 78°F 1995 | 18°F 1962 | 26% | 0% |
| Dec 14 | 56°F | 36°F | 80°F 1995 | 16°F 1985 | 26% | 0% |
| Dec 15 | 56°F | 36°F | 80°F 2021 | 10°F 1989 | 26% | 0% |
| Dec 16 | 56°F | 36°F | 83°F 2021 | 13°F 1989 | 26% | 0% |
| Dec 17 | 56°F | 35°F | 79°F 2006 | 14°F 1989 | 26% | 0% |
| Dec 18 | 55°F | 35°F | 80°F 2012 | 16°F 2016 | 26% | 0% |
| Dec 19 | 55°F | 35°F | 80°F 2012 | 16°F 1983 | 26% | 0% |
| Dec 20 | 55°F | 35°F | 78°F 2025 | 17°F 1989 | 26% | 0% |
| Dec 21 | 55°F | 35°F | 78°F 1981 | 6°F 1989 | 26% | 0% |
| Dec 22 | 55°F | 35°F | 86°F 2010 | -1°F 1989 | 26% | 0% |
| Dec 23 | 54°F | 35°F | 80°F 2025 | 9°F 1989 | 26% | 0% |
| Dec 24 | 54°F | 35°F | 79°F 2015 | 9°F 1983 | 26% | 1% |
| Dec 25 | 54°F | 34°F | 84°F 2021 | 5°F 1983 | 26% | 1% |
| Dec 26 | 54°F | 34°F | 84°F 2025 | 15°F 1983 | 26% | 1% |
| Dec 27 | 54°F | 34°F | 82°F 2005 | 23°F 2009 | 26% | 1% |
| Dec 28 | 54°F | 34°F | 84°F 2021 | 21°F 1983 | 26% | 1% |
| Dec 29 | 54°F | 34°F | 78°F 2021 | 10°F 1983 | 26% | 1% |
| Dec 30 | 53°F | 34°F | 82°F 2024 | 6°F 1983 | 26% | 1% |
| Dec 31 | 53°F | 34°F | 77°F 1964 | 13°F 1976 | 26% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (CST).
- December 1
- sunrise 7:11 AM, sunset 5:20 PM
- December 31
- sunrise 7:29 AM, sunset 5:30 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00415094 (Lavon Dam), public domain. Records: NOAA GHCN-Daily, station USC00413133, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.