Climate averages 1991–2020

Salem, United States weather
in December.

A cool, very wet month: the coolest and the wettest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high 8.1°C Daytime mean, December
Average low 1.9°C Night-time mean, December
Rainfall 181 mm 17 days with ≥1 mm
Daylight 9 h Sunrise to sunset, per day
Every month in Salem · average highYear overview

December is a cool month in Salem, United States: daytime highs average 8.1°C and nights cool to about 1.9°C. By daytime temperature it is the coolest month of the year.

Expect about 181 mm of rain on roughly 17 days, which makes December a very wet month (the wettest month of the year). Daylight, from sunrise to sunset, lasts about 8 h 51 min on an average December day.

The nearest other city in this atlas is Beaverton (63 km away). In December its highs average 7.3°C, 0.8°C cooler than Salem, United States, with 193 mm of rain.

Among the 498 cities listed in the United States, Salem, United States ranks 284th of 498 for the warmest December highs and joint 485th of 498 for the driest December (rainfall, lowest first). The mean December high of those 498 cities is 10.5°C; Salem, United States is 2.4°C cooler than that mean.

From December to January, average highs rise by 0.6°C to 8.8°C, and monthly rainfall falls from 181 mm to 154 mm.

The annual picture

December in context

30-year average
Average highAverage low°C
Average daily high and low temperatures by month The same values are available in the monthly table below. Lines show mean daily maxima and minima, not a forecast interval. -5051015202530 JanFebMarAprMayJunJulAugSepOctNovDec

Monthly rainfall

Average total · mm
Average monthly rainfall totalsEach bar is a mean monthly total over 1991–2020. Full numbers are in the table. JanFebMarAprMayJunJulAugSepOctNovDec 2000

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Salem, United States climate table

1991–2020
Monthly climate averages for Salem, United States, 1991–2020
MonthAverage highHigh / lowAverage lowRainfall mm/monthRain days ≥1 mm/dayDaylight hours/dayDay­light h/day
January 8.8°C2.0°C2.0°C15415.99.29 h
February 10.3°C2.1°C2.1°C11913.910.410 h
March 12.3°C3.5°C3.5°C12815.711.912 h
April 14.6°C5.1°C5.1°C9214.313.513 h
May 18.6°C8.2°C8.2°C569.014.815 h
June 22.0°C10.8°C10.8°C305.915.516 h
July 27.6°C13.7°C13.7°C7.91.915.215 h
August 27.9°C14.1°C14.1°C102.014.114 h
September 24.5°C12.0°C12.0°C324.812.613 h
October 17.4°C7.9°C7.9°C8710.311.011 h
November 11.4°C4.4°C4.4°C15315.99.610 h
December, selected 8.1°C1.9°C1.9°C18116.88.99 h

Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.

Compare places

December in nearby cities

Distance from Salem

Read the numbers correctly

Climate, not a promise.

These patterns help compare months. They cannot tell you the weather on a specific day of your trip.

Sources, method and limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Salem) is explained once on the Salem, United States year overview and on the Sources, method and limits page.