Tri-Cities weather
May 10, 2023
Starting the day with just a few clouds moving about the Columbia Basin. A weak trough is forecast to pass overhead so that with daytime heating, cumulus development is likely starting midday for partly cloudy skies this afternoon. Scattered thunderstorms in the mountains will add some high clouds to the mix into the evening hours but storms are not likely to make it into lowland areas.
Continuing the warming trend with highs in the mid- to upper-70s. Look for lows around 50 tonight despite mostly clear skies, though some small and well sheltered valleys could get into the upper 30s.
Conditions are forecast to be pretty similar on Thursday with some clouds in the afternoon as an upper level ridge builds over the Pacific Northwest. Highs will be a few degrees warmer – reaching into the low 80s in the afternoon. The upward climb continues with the Tri-Cities reaching the 90s on Saturday and close to 100°F by Monday.
Modeling favors above average temperatures and below average precipitation in the region for the remainder of the month. Today, the average high in the Tri-Cities is 75°F and the average low is 44°F. This does not mean that every day for the rest of the month will be above average, but that the expectation is that taken as a whole the average temperature for the remainder of the month will be above climatological norms.
Area waterbodies, including the Columbia and Snake Rivers, will be cold despite the hot air temperatures. It takes longer for water to warm up than it takes air. Additionally, warmer temperatures will increase snowmelt in the mountains. On May 8 the average water temperature of the Columbia at McNary Dam was 54°F and the Snake at Ice Harbor was 53°F. In water this cold, people can become exhausted in as little as an hour and the expected survival time is one to six hours.
Flooding is not currently forecast in the Tri-Cities area but rivers (especially the Yakima) will be running higher and swifter than usual. The Naches River is expected to remain just below flood stage for at least the next week.
