Climate averages 1991–2020
Tri-Cities weather
in October.
A mild, fairly dry month: the 7th warmest and the 7th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
October is a mild month in Tri-Cities: daytime highs average 18.9°C and nights cool to about 7.9°C. By daytime temperature it is the 7th warmest of the 12 months.
Expect about 22 mm of rain on roughly 5 days, which makes October a fairly dry month (the 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 10 h 58 min on an average October day.
The nearest other city in this atlas is Kennewick (6 km away). In October its highs average 18.7°C, about as warm as Tri-Cities, with 22 mm of rain.
Among the 498 cities listed in the United States, Tri-Cities ranks joint 298th of 498 for the warmest October highs and joint 92nd of 498 for the driest October (rainfall, lowest first). The mean October high of those 498 cities is 21.4°C; Tri-Cities is 2.4°C cooler than that mean.
From October to November, average highs fall by 8.3°C to 10.7°C, and monthly rainfall rises from 22 mm to 29 mm.
The annual picture
October in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Tri-Cities climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 6.0°C-1.5°C | -1.5°C | 34 | 8.1 | 9.19 h |
| February | 9.3°C-0.3°C | -0.3°C | 23 | 6.2 | 10.310 h |
| March | 14.3°C2.8°C | 2.8°C | 24 | 5.9 | 11.912 h |
| April | 19.3°C6.6°C | 6.6°C | 17 | 4.9 | 13.514 h |
| May | 25.0°C11.5°C | 11.5°C | 18 | 4.5 | 15.015 h |
| June | 28.9°C15.3°C | 15.3°C | 13 | 2.8 | 15.716 h |
| July | 34.2°C19.2°C | 19.2°C | 3.8 | 1.0 | 15.415 h |
| August | 33.2°C18.6°C | 18.6°C | 4.2 | 1.0 | 14.214 h |
| September | 27.5°C14.0°C | 14.0°C | 6.9 | 1.8 | 12.613 h |
| October, selected | 18.9°C7.9°C | 7.9°C | 22 | 5.0 | 11.011 h |
| November | 10.7°C2.3°C | 2.3°C | 29 | 7.3 | 9.59 h |
| December | 5.6°C-1.2°C | -1.2°C | 35 | 8.4 | 8.79 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
October in nearby cities
- Kennewick in OctoberUnited States · 6 kmHigh 18.7°C · Low 7.8°C · 22 mm rain
- Yakima in OctoberUnited States · 108 kmHigh 16.4°C · Low 5.1°C · 30 mm rain
- Spokane in OctoberUnited States · 207 kmHigh 15.1°C · Low 4.9°C · 46 mm rain
- Spokane Valley in OctoberUnited States · 217 kmHigh 14.7°C · Low 4.5°C · 52 mm rain
- Auburn in OctoberUnited States · 259 kmHigh 14.9°C · Low 7.4°C · 131 mm rain
- Kent in OctoberUnited States · 263 kmHigh 15.2°C · Low 7.8°C · 134 mm rain
- Gresham in OctoberUnited States · 264 kmHigh 16.0°C · Low 7.1°C · 147 mm rain
- Federal Way in OctoberUnited States · 266 kmHigh 14.3°C · Low 7.2°C · 131 mm rain
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 limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Tri-Cities) is explained once on the Tri-Cities year overview and on the Sources, method and limits page.
Kennewick lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.