Portland weather in December: Portland, Oregon: normal highs, lows, rain and records for December
Portland in December has a normal high of 47°F and a normal low of 36°F, a daily mean of 42°F, falling from 49°F on the 1st to 46°F by the 31st. Measurable precipitation falls on 19 days in a normal December, 5.77 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 8°C and low of 2°C, 147 mm of precipitation and 3 cm of snow in December.
- NOAA stationPortland International Airport
- Station IDUSW00024229
- Location45.59°N 122.60°W
- Elevation19 ft (6 m)
- From the center4 miles
- Population635,749
- Jan 48° 36°
- Feb 52° 37°
- Mar 57° 40°
- Apr 62° 44°
- May 69° 49°
- Jun 74° 54°
- Jul 82° 59°
- Aug 82° 59°
- Sep 77° 54°
- Oct 64° 47°
- Nov 54° 41°
- Dec 47° 36°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Portland in December?
The normal high is 47°F and the normal low 36°F, for a daily mean of 41.6°F. December is 5.5°F cooler than November and 0.3°F cooler than January. December is the 12th warmest month of the year in Portland and the wettest. Across the month the normal high falls 3°F, from 49°F on December 1 to 46°F on December 31. From one year to the next December's mean temperature typically moves about 2.3°F either way (NOAA's standard deviation), so roughly two Decembers in three average between 39°F and 44°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 63%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| December 1 | 49°F | 38°F | 62% | 42% |
| December 8 | 48°F | 37°F | 62% | 42% |
| December 15 | 47°F | 36°F | 63% | 42% |
| December 22 | 46°F | 36°F | 63% | 42% |
| December 31 | 46°F | 36°F | 62% | 42% |
Every day of December: normal high, low and chance of precipitation (warmest afternoon December 1, coldest night December 21)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| December 1 | 49°F | 38°F | 62% | 42% | 9 h |
| December 2 | 49°F | 38°F | 62% | 42% | 9 h |
| December 3 | 49°F | 38°F | 62% | 42% | 9 h |
| December 4 | 49°F | 37°F | 62% | 42% | 8 h 50 min |
| December 5 | 48°F | 37°F | 62% | 42% | 8 h 50 min |
| December 6 | 48°F | 37°F | 62% | 42% | 8 h 50 min |
| December 7 | 48°F | 37°F | 62% | 42% | 8 h 50 min |
| December 8 | 48°F | 37°F | 62% | 42% | 8 h 50 min |
| December 9 | 48°F | 37°F | 63% | 42% | 8 h 50 min |
| December 10 | 47°F | 37°F | 63% | 42% | 8 h 50 min |
| December 11 | 47°F | 36°F | 63% | 42% | 8 h 50 min |
| December 12 | 47°F | 36°F | 63% | 42% | 8 h 50 min |
| December 13 | 47°F | 36°F | 63% | 42% | 8 h 50 min |
| December 14 | 47°F | 36°F | 63% | 42% | 8 h 40 min |
| December 15 | 47°F | 36°F | 63% | 42% | 8 h 40 min |
| December 16 | 47°F | 36°F | 63% | 42% | 8 h 40 min |
| December 17 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 18 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 19 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 20 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 21 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 22 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 23 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 24 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 25 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 26 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 27 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 28 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 29 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 30 | 46°F | 36°F | 63% | 42% | 8 h 40 min |
| December 31 | 46°F | 36°F | 62% | 42% | 8 h 40 min |
- Normal high
- 47°FDecember average
- Normal low
- 36°FDecember average
- Precipitation
- 5.77 inmonth total
- Days with precipitation
- 190.01 inch or more
- Snowfall
- 1.2 inmonth total
- Nights at 32°F or colder
- 8
- Daylight
- 9 h to 8 h 40 minDecember 1 to December 31
- Sunshine
- 52%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00024229; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain or snow in Portland in December?
On a given December day the chance of 0.01 inch or more is 63% on average, highest around December 19 (63%). In all, 5.77 in falls on 19 days of a normal December, 1 of them with an inch or more.
In a normal December in Portland, 8 nights fall to freezing, 1 days stay below freezing all day and snowfall averages 1.2 inches.
Snow falls on 1 day in a normal December, and an inch or more covers the ground on 1 day.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00024229.
How humid and windy is Portland in December?
At 3 p.m. the normal temperature is 43°F with 74% relative humidity and a dew point of 36°F; at 6 a.m. it is 39°F with 84% humidity. The wind averages 9.4 mph, most often from the southeast in the afternoon. A dew point under 50°F feels dry.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 39°F | 34°F | 84% | 8.5 mph | – |
| 9 a.m. | 39°F | 34°F | 83% | 8.8 mph | – |
| noon | 42°F | 35°F | 76% | 10.0 mph | – |
| 3 p.m. | 43°F | 36°F | 74% | 10.4 mph | – |
| 6 p.m. | 41°F | 35°F | 79% | 10.0 mph | – |
| 9 p.m. | 40°F | 35°F | 81% | 9.7 mph | 21% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00024229. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for December in Portland?
The warmest December temperature on Portland's official record (since 1940) is 67°F, on December 4, 2023; the coldest is 6°F, on December 16, 1964. The wettest December brought 15.24 in (2015); the snowiest, 19.0 inches (2008).
The December mean against the 1991-2020 normal of 41.6°F: 2021 41.1°F (−0.5), 2022 39.0°F (−2.6), 2023 46.1°F (+4.5), 2024 44.9°F (+3.3), 2025 47.4°F (+5.8). 3 of 5 ran warmer than normal.
| December | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 41.1°F | −0.5°F | 7.10 in |
| 2022 | 39.0°F | −2.6°F | 7.76 in |
| 2023 | 46.1°F | +4.5°F | 8.73 in |
| 2024 | 44.9°F | +3.3°F | 6.79 in |
| 2025 | 47.4°F | +5.8°F | 8.51 in |
Source: records: ACIS, NWS threaded record PDXthr; recent months: ACIS, station USW00024229. Records and recent months use complete months only.
How does December in Portland compare across Oregon?
Across the 105 places PlainClimate covers in Oregon, December normal highs run from 33°F in Halfway to 55°F in Bandon; Portland's is 47°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.