Sunnyside in Winter
In winter (December, January and February), Sunnyside sees average daytime highs around 42°F and overnight lows near 29°F, with 4.3 in of precipitation over about 25 wet days across the season. It is the coldest season of the year and the wettest season of the year.
Over the season highs climb from about 41°F in early December to 49°F by late February. The sky is clear or mostly clear about 23% of the time across winter, and the air most often feels dry.
Winter is Sunnyside's weakest season of the year to visit on our travel score. For the whole year in context, see Sunnyside's year-round climate.
- Avg daytime high
- 42°F
- coldest season of the year
- Avg overnight low
- 29°F
- Precipitation
- 4.3 in
- 25 wet days
- Avg wind
- 5 mph
- Travel score
- 0.5
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Sunnyside in Winter
Over the season highs climb from about 41°F in early December to 49°F by late February.
A typical winter day in Sunnyside reaches about 42°F and drops to 29°F overnight. The warmest of the three months is February, the coolest December.
How winter really feels in Sunnyside
Once humidity and wind are folded in, winter brings about 0 days that feel above 90°F and 90 that feel at or below 32°F.
The story in winter is cold — wind chill drags the overnight "feels like" below the raw low.
Sunnyside weather by month
How the three winter months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 40° / 28° | 1.5 | 9.2 | 3.5 | 8.8 | 0.1 |
| Feb | 47° / 31° | 1.1 | 6.3 | 1.9 | 10 | 1.5 |
| Mar | 55° / 36° | 1.0 | 6.6 | 0.6 | 11.6 | 3.9 |
| Apr | 65° / 43° | 0.7 | 4.6 | 0.1 | 13.3 | 6.5 |
| May | 75° / 51° | 0.7 | 4.2 | 0 | 14.7 | 7.7 |
| Jun | 82° / 57° | 0.4 | 3 | 0 | 15.5 | 7.2 |
| Jul | 91° / 63° | 0.2 | 1.3 | 0 | 15.2 | 4.6 |
| Aug | 90° / 61° | 0.2 | 1.1 | 0 | 14 | 5.1 |
| Sep | 80° / 53° | 0.3 | 1.9 | 0 | 12.3 | 8.0 |
| Oct | 64° / 43° | 1.0 | 5.1 | 0.1 | 10.7 | 6.4 |
| Nov | 48° / 34° | 1.3 | 7.8 | 1 | 9.2 | 2.0 |
| Dec | 39° / 28° | 1.7 | 9 | 3.5 | 8.5 | 0.0 |
Cloud cover in Winter
The sky is clear or mostly clear about 23% of the time across winter.
Chance of precipitation in Winter
Sunnyside gets around 4.3 in of rain and snow over 25 wet days across winter. The line is the day-by-day chance of measurable precipitation.
Humidity in Winter
Most of winter feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Winter
Winds average 5 mph across winter.
Sunrise & sunset in Winter
Daylight runs from about 8 h 42 min in early December to 10 h 42 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Winter
Average shortwave solar energy reaching the ground each day across winter, about 1.8 kWh/m².
Is winter a good time to visit Sunnyside?
Our two travel scores rate winter for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
winter is a weaker month for outdoor sightseeing in Sunnyside.
What to pack for Sunnyside in Winter
From winter's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In winter, Sunnyside sees daytime highs around 42°F and nights near 29°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 25 days see rain.
UV index in Sunnyside in Winter
Clear-sky midday UV across winter averages around 1. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Sunnyside peaks around July 16 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 14 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 2 | 4 | 5 | 7 | 6 | 9 | 6 | 5 | 4 | 1 | 1 |
| Level | Low | Low | Moderate | High | Very high | High | Very high | High | Moderate | Moderate | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 2 | Low |
| Mar | 4 | Moderate |
| Apr | 5 | High |
| May | 7 | Very high |
| Jun | 6 | High |
| Jul | 9 | Very high |
| Aug | 6 | High |
| Sep | 5 | Moderate |
| Oct | 4 | Moderate |
| Nov | 1 | Low |
| Dec | 1 | Low |
Air quality in Sunnyside in Winter
Average fine-particle pollution (PM2.5) through the year — so you can see where winter falls, not just the annual average.
Air quality in Sunnyside is worst in August — around 30 µg/m³ PM2.5 (moderate), about 4.0× the cleanest month (December, 7 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 9 | 10 | 12 | 10 | 9 | 10 | 13 | 30 | 23 | 10 | 10 | 7 |
| Level | Good | Good | Good | Good | Good | Good | Moderate | Moderate | Moderate | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 9 | Good |
| Feb | 10 | Good |
| Mar | 12 | Good |
| Apr | 10 | Good |
| May | 9 | Good |
| Jun | 10 | Good |
| Jul | 13 | Moderate |
| Aug | 30 | Moderate |
| Sep | 23 | Moderate |
| Oct | 10 | Good |
| Nov | 10 | Good |
| Dec | 7 | Good |
Where is Sunnyside?
Sunnyside sits at 46.3°N, 120.0°W, 745 ft above sea level, in United States. The nearest listed city is Yakima, 30 mi away.
Topography around Sunnyside
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Sunnyside.
Within 2 miles, the terrain around Sunnyside has only modest variations in elevation — a maximum elevation change of 289 ft around an average of 764 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 2,152 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 5,568 ft.
The land around Sunnyside is covered by cropland (34%), grassland (29%) and artificial surfaces (24%) within 2 miles, grassland (46%) and cropland (38%) within 10 miles, and grassland (62%) and cropland (24%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Sunnyside (46.3237°, -120.0087°, elevation 745 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.