Riverhead Weather in December
Average highs run from 49°F on December 1 to 42°F on December 31, and lows from 36°F to 28°F. Normal precipitation for the month is 4.58 in over about 11 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
- 45°F
- Average low
- 32°F
- Precipitation
- 4.58 in
- Snowfall
- 4.1 in
- Record high
- 71°FDec 4, 1998
- Record low
- -7°FDec 23, 2009
- Chance of a freeze
- 100%
- Daylight
- 9 h 27 min to 9 h 17 min
- Cloud cover
- 63%
- Humidity
- 82%
- Dew point
- 34°F
- Wind
- 13.2 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 | 49°F | 36°F | 67°F 2001 | 12°F 1965 | 32% | 3% |
| Dec 2 | 49°F | 35°F | 58°F 1998 | 12°F 2024 | 32% | 3% |
| Dec 3 | 48°F | 35°F | 64°F 1998 | 6°F 2000 | 32% | 4% |
| Dec 4 | 48°F | 35°F | 71°F 1998 | 5°F 2000 | 32% | 4% |
| Dec 5 | 48°F | 35°F | 66°F 2001 | 11°F 2000 | 32% | 4% |
| Dec 6 | 47°F | 34°F | 62°F 2001 | 4°F 2002 | 33% | 4% |
| Dec 7 | 47°F | 34°F | 60°F 1953 | -1°F 2002 | 33% | 4% |
| Dec 8 | 47°F | 34°F | 62°F 1951 | 10°F 2008 | 33% | 5% |
| Dec 9 | 47°F | 34°F | 62°F 1966 | 3°F 2002 | 33% | 5% |
| Dec 10 | 46°F | 33°F | 60°F 2015 | 5°F 2010 | 33% | 5% |
| Dec 11 | 46°F | 33°F | 62°F 2024 | 6°F 1968 | 33% | 5% |
| Dec 12 | 46°F | 33°F | 66°F 2015 | 10°F 2013 | 33% | 5% |
| Dec 13 | 46°F | 33°F | 63°F 2015 | 11°F 1960 | 33% | 6% |
| Dec 14 | 45°F | 32°F | 62°F 2015 | 5°F 2005 | 34% | 6% |
| Dec 15 | 45°F | 32°F | 62°F 2015 | 1°F 1962 | 34% | 6% |
| Dec 16 | 45°F | 32°F | 57°F 2021 | 6°F 1961 | 34% | 6% |
| Dec 17 | 45°F | 32°F | 60°F 2021 | 4°F 1962 | 34% | 6% |
| Dec 18 | 44°F | 31°F | 62°F 2023 | 6°F 2011 | 34% | 7% |
| Dec 19 | 44°F | 31°F | 59°F 2013 | 6°F 2011 | 34% | 7% |
| Dec 20 | 44°F | 31°F | 64°F 2013 | 6°F 1955 | 34% | 7% |
| Dec 21 | 44°F | 31°F | 60°F 2018 | 4°F 1955 | 34% | 7% |
| Dec 22 | 43°F | 30°F | 61°F 2013 | 5°F 1955 | 34% | 7% |
| Dec 23 | 43°F | 30°F | 63°F 2015 | -7°F 2009 | 34% | 7% |
| Dec 24 | 43°F | 30°F | 63°F 2015 | 6°F 2000 | 34% | 7% |
| Dec 25 | 43°F | 30°F | 66°F 2015 | 5°F 1967 | 34% | 8% |
| Dec 26 | 42°F | 29°F | 57°F 1964 | 7°F 1968 | 34% | 8% |
| Dec 27 | 42°F | 29°F | 63°F 2015 | 7°F 2017 | 34% | 8% |
| Dec 28 | 42°F | 29°F | 57°F 2018 | 3°F 2004 | 34% | 8% |
| Dec 29 | 42°F | 29°F | 56°F 2013 | 2°F 2017 | 34% | 8% |
| Dec 30 | 42°F | 29°F | 57°F 2024 | 2°F 1962 | 34% | 8% |
| Dec 31 | 42°F | 28°F | 56°F 2022 | 2°F 1962 | 34% | 8% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (EST).
- December 1
- sunrise 6:56 AM, sunset 4:23 PM
- December 31
- sunrise 7:15 AM, sunset 4:32 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00307134 (Riverhead Rsch Farm), public domain. Records: NOAA GHCN-Daily, station USW00014719, 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.