Benton County climate

Benton County Weather in December

NOAA 1991-2020 normals for Prosser, 19.5 km from Benton County

Average highs run from 43°F on December 1 to 38°F on December 31, and lows from 28°F to 26°F. Normal precipitation for the month is 1.33 in over about 8 wet days.

December day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Benton County, in °F, with the record for each date.-20020406080151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

December at a glance

Average high
40°F
Average low
26°F
Precipitation
1.33 in
Record high
69°FDec 1, 2021
Record low
-10°FDec 30, 1968
Chance of a freeze
100%
Daylight
8 h 53 min to 8 h 41 min
Cloud cover
74%
Humidity
79%
Dew point
28°F
Wind
8.3 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation.

DateNormal highNormal lowRecord highRecord lowChance wet
Dec 143°F28°F69°F 20214°F 198526%
Dec 243°F28°F65°F 19726°F 198526%
Dec 342°F28°F66°F 195815°F 197626%
Dec 442°F27°F65°F 194612°F 201326%
Dec 542°F27°F59°F 19668°F 201326%
Dec 641°F27°F60°F 194610°F 201326%
Dec 741°F27°F63°F 19707°F 200926%
Dec 841°F27°F66°F 2015-4°F 197227%
Dec 940°F27°F69°F 1946-2°F 197227%
Dec 1040°F27°F67°F 2025-1°F 197227%
Dec 1140°F26°F65°F 2014-5°F 197227%
Dec 1240°F26°F64°F 1955-4°F 197227%
Dec 1340°F26°F62°F 1946-3°F 197227%
Dec 1439°F26°F61°F 20020°F 197226%
Dec 1539°F26°F69°F 20257°F 197226%
Dec 1639°F26°F65°F 1959-3°F 196426%
Dec 1739°F26°F63°F 2025-6°F 196426%
Dec 1839°F26°F59°F 20240°F 196426%
Dec 1939°F26°F58°F 19664°F 198426%
Dec 2038°F26°F64°F 19944°F 200826%
Dec 2138°F26°F64°F 1994-6°F 199026%
Dec 2238°F26°F63°F 1972-5°F 199026%
Dec 2338°F26°F60°F 1950-4°F 198326%
Dec 2438°F26°F64°F 1950-3°F 198326%
Dec 2538°F26°F56°F 19500°F 198326%
Dec 2638°F26°F63°F 19800°F 198326%
Dec 2738°F26°F65°F 19802°F 194826%
Dec 2838°F26°F63°F 1967-8°F 199026%
Dec 2938°F26°F59°F 1980-5°F 199026%
Dec 3038°F26°F62°F 1949-10°F 196826%
Dec 3138°F26°F57°F 1945-2°F 196826%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Benton County, in percent.01020301102030
  • Chance of a wet day

Sunrise and sunset

Times for 2026, local time (PST).

December 1
sunrise 7:21 AM, sunset 4:14 PM
December 31
sunrise 7:41 AM, sunset 4:22 PM

Every day of December: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00456768 (Prosser), public domain. Records: NOAA GHCN-Daily, station USC00457015, 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.