Tri-Cities in Fall
In fall (September, October and November), Tri-Cities sees average daytime highs around 66°F and overnight lows near 44°F, with 2.3 in of precipitation over about 14 wet days across the season. It is the 3rd-warmest season and the 3rd-wettest season.
Over the season highs ease from about 86°F in early September to 44°F by late November. The sky is clear or mostly clear about 43% of the time across fall, and the air most often feels dry.
Fall is Tri-Cities's 2nd-best season to visit on our travel score. For the whole year in context, see Tri-Cities's year-round climate.
- Avg daytime high
- 66°F
- 3rd-warmest season
- Avg overnight low
- 44°F
- Precipitation
- 2.3 in
- 14 wet days
- Avg wind
- 5 mph
- Travel score
- 5.6
- 2nd-best season
- Months
- Sep · Oct · Nov
Temperature in Tri-Cities in Fall
Over the season highs ease from about 86°F in early September to 44°F by late November.
A typical fall day in Tri-Cities reaches about 66°F and drops to 44°F overnight. The warmest of the three months is September, the coolest November.
How fall really feels in Tri-Cities
Once humidity and wind are folded in, fall brings about 0 days that feel above 90°F and 22 that feel at or below 32°F.
The story in fall is cold — wind chill drags the overnight "feels like" below the raw low.
Tri-Cities weather by month
How the three fall months (September, October and November) 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 | 41° / 29° | 1.3 | 8.1 | 2.3 | 8.8 | 0.2 |
| Feb | 48° / 32° | 0.9 | 6.2 | 1.3 | 10 | 2.0 |
| Mar | 58° / 38° | 0.9 | 5.9 | 0.4 | 11.6 | 4.6 |
| Apr | 68° / 44° | 0.7 | 4.9 | 0 | 13.3 | 6.9 |
| May | 77° / 52° | 0.7 | 4.5 | 0 | 14.7 | 7.6 |
| Jun | 84° / 58° | 0.5 | 2.8 | 0 | 15.5 | 6.6 |
| Jul | 93° / 64° | 0.1 | 1 | 0 | 15.2 | 3.9 |
| Aug | 92° / 62° | 0.2 | 1 | 0 | 14 | 4.5 |
| Sep | 81° / 54° | 0.3 | 1.8 | 0 | 12.3 | 7.7 |
| Oct | 66° / 44° | 0.9 | 5 | 0 | 10.7 | 6.7 |
| Nov | 50° / 35° | 1.1 | 7.3 | 0.7 | 9.2 | 2.4 |
| Dec | 41° / 29° | 1.4 | 8.4 | 2.4 | 8.5 | 0.1 |
Cloud cover in Fall
The sky is clear or mostly clear about 43% of the time across fall.
Chance of precipitation in Fall
Tri-Cities gets around 2.3 in of rain and snow over 14 wet days across fall. The line is the day-by-day chance of measurable precipitation.
Humidity in Fall
Most of fall feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Fall
Winds average 5 mph across fall.
Sunrise & sunset in Fall
Daylight runs from about 13 h 12 min in early September to 8 h 42 min by late November. The lit band spans sunrise to sunset each day.
Solar energy in Fall
Average shortwave solar energy reaching the ground each day across fall, about 3.3 kWh/m².
Is fall a good time to visit Tri-Cities?
Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
fall is a reasonable time to visit Tri-Cities for sightseeing.
What to pack for Tri-Cities in Fall
From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In fall, Tri-Cities sees daytime highs around 66°F and nights near 44°F. Pack light clothes and a warm layer. Worth having: sun protection. About 14 days see rain.
UV index in Tri-Cities in Fall
Clear-sky midday UV across fall averages around 3 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Tri-Cities peaks around July 16 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 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 | 8 | 6 | 5 | 3 | 1 | 1 |
| Level | Low | Low | Moderate | Moderate | 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 | Moderate |
| May | 7 | Very high |
| Jun | 6 | High |
| Jul | 8 | Very high |
| Aug | 6 | High |
| Sep | 5 | Moderate |
| Oct | 3 | Moderate |
| Nov | 1 | Low |
| Dec | 1 | Low |
Air quality in Tri-Cities in Fall
Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual average.
Air quality in Tri-Cities is worst in August — around 27 µg/m³ PM2.5 (moderate), about 3.1× the cleanest month (December, 9 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) | 10 | 11 | 14 | 11 | 9 | 10 | 13 | 27 | 21 | 12 | 11 | 9 |
| Level | Good | Good | Moderate | Good | Good | Good | Moderate | Moderate | Moderate | Moderate | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 10 | Good |
| Feb | 11 | Good |
| Mar | 14 | Moderate |
| Apr | 11 | Good |
| May | 9 | Good |
| Jun | 10 | Good |
| Jul | 13 | Moderate |
| Aug | 27 | Moderate |
| Sep | 21 | Moderate |
| Oct | 12 | Moderate |
| Nov | 11 | Good |
| Dec | 9 | Good |
Where is Tri-Cities?
Tri-Cities sits at 46.2°N, 119.2°W, 348 ft above sea level, in United States. The nearest listed city is Kennewick, 3.7 mi away.
Topography around Tri-Cities
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Tri-Cities.
Within 2 miles, the terrain around Tri-Cities has only modest variations in elevation — a maximum elevation change of 197 ft around an average of 400 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,677 ft; within 50 miles, large variations in elevation — a maximum elevation change of 3,894 ft.
The land around Tri-Cities is covered by artificial surfaces (32%) and grassland (28%) within 2 miles, grassland (38%) and cropland (28%) within 10 miles, and grassland (51%) and cropland (42%) 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 Tri-Cities (46.2454°, -119.1962°, elevation 348 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.