Weather in Tri-Cities in January

United States · 20-year averages, January

A hard month. January asks something of you. Go in knowing what. Highs sit at 6.9 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.

January ranks 11 of 12 — near the bottom of Tri-Cities's year. September is the month that works, and the swing between the two is 53 points, which is a different holiday rather than a slightly better one.

Rain on 9 days, 0 of them heavy. Enough to need a plan B, not enough to need a plan around it. Layers, and a genuinely waterproof outer — at 6.9 °C the difference between a good day and a miserable one is entirely down to what you are wearing.

What the averages hide

Averages flatten a month, and this one hides a few things: 15 nights fall below freezing. Across the twenty years measured, the hottest January day reached 19.8 °C and the coldest night fell to -16.4 °C.

January is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest January on record still delivered 66 mm against 15 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 36 mm average is a reasonable planning figure, not a promise.

Wind is light at 8.9 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 81%, which at 6.9 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.

How January sits in the year

Temperatures hold steady either side: 6.7 °C in December, 6.9 here, 10.2 in February. Nothing about the timing within the month matters much.

Daylight in January

January sits at the dark end of Tri-Cities's year — 9 hours of daylight against 15.8 at midsummer, gaining 0.9 hours across the month. Sightseeing days are genuinely shorter, and an itinerary built for summer will not fit.

An inland climate

With no coast nearby, the year swings a fair way — 34.6 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage.

How busy it gets

Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

January in Tri-Cities versus nearby

If Tri-Cities is one option among several, the nearby comparison is worth making. Spokane is the weaker option in January — 5.1 °C cooler, 5 days more rain. Portland is the weaker option in January — within a degree on temperature, 10 days more rain.

So: January is a compromise. September is 50 points better and is what Tri-Cities is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Tri-Cities

MonthHigh °CLow °CRain daysRain mmHumidity %Daylight hScore
January6.9-0.3 93681943
February10.20.6 7257210.357
March14.93.6 8276411.871
April18.96.2 7245813.585
May24.510.9 7275214.989
June28.514.3 5214815.885
July34.318.3 144115.548
August33.218.1 274114.269
September27.413.7 3114712.693
October19.38.1 624601188
November11.83 829719.561
December6.7-0.3 1042798.640

See all twelve months in Tri-Cities, or where else to go in January.

Planning the rest of the trip

Built and maintained by Amit Sharma, Auckland, New Zealand. I build these sites so the answer is free and the data is public.

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