Weather 9-16-20

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Continued positioning of an area of low pressure offshore against the generally negatively titled inland high-pressure ridge is keeping a general southerly flow in place over the Inland Northwest. There doesn`t seem to be any shortwaves of significance taking the provided path up into the state but the smoke from regional fires continues to do so. With this in mind, haze and smoke is expected to continue to impact the area at least through Thursday.

Weather for today and Thursday, more of the same with widespread smoke and unhealthy air with afternoon high temperatures generally in the mid 70’s. There is a 20% chance of isolated showers Thursday night.

Weather forecast for Friday will feature an approaching low-pressure trough that’s been sitting off the Pacific coast. Northcentral Washington can expect mostly cloudy skies, less smoke and haze and a 40% chance of daytime showers with highs in the upper 70’s to around 80 degrees. The chance for rain goes up to 50% Friday night. There is also a very slight chance for thunderstorms Friday afternoon and any that do develop will be capable of brief heavy rain, lightning and gusty winds.

Saturday weather looks to be a bit breezy with a 30% chance of afternoon showers as the area of low pressure pushes off to the east. The Columbia Basin could see wind gusts of up to 20-30 mph.

The Inland Northwest will dry out on Sunday and heading into the early part of next week under a dry, zonal flow. Medium range weather models do show a deep trough of lower pressure developing in the Gulf of Alaska with a strong upper level jet around the base of the trough. There is uncertainty with where exactly this jet will fixate, but it’s possible that the region will turn much wetter around the middle to late portions of next week. This would be a welcomed site for fires and dampening smoke across the Northwest. Even before any rains arrive next week, we should see a much-improved smoke situation with the westerly flow pushing smoke mostly south and east of eastern Washington. This will help to improve air quality tremendously.

Under sunny skies Sunday, Monday and Tuesday expect afternoon high temperatures in the mid to upper 70’s.