Some of you complain that you miss the autumn weather. That endless summer is not your cup of tea.
Well, the weather god heard your complaint and the forecast changed early next week.
Rain and cooler weather to come – but there’s more you should know.
Cloudy today over much of the West due to a combination of shore currents, longer nights and smoke particles contributing to fog and low clouds (see satellite image around noon today). Also, a lot of smoke from the Lake Wenatchee fires is heading towards Wenatchee, with very high concentrations of particles hitting the Apple Capitol.
PurpleAir particle concentration. Purple is very bad
This will continue into the weekend as high pressure continues in the eastern Pacific.
But on Monday, everything changed when a sharp, energetic low-pressure gully crept around the upper ridge and pushed into the NW (see upper air map – 500 hPa pressure, about 18000 ft – at 5 p.m. Mondy)
This trough will bring cooler air from the northwest and rain, reducing peaks on Monday and Tuesday to less than 60 seconds. You will think about some hot chocolate and your coat.
Here’s the rainfall forecast for the 24 hours ending at 5 a.m. Tuesday. A few tenths of an inch in the lowlands, a little more in the mountains. Enough to wet the ground but not much more.
This trough will move south into California, bringing some showers and potentially some strong winds into the Golden State (see upper map at 5 p.m. Wednesday).
This is an odd pattern for the Northwest, resulting in a strong winter (from the east) current flowing through the Northwest. You can clearly see this in the low-level weather map (about 5000 ft) on Wednesday 11 a.m. (below)
I worry about this model. There will be strong winter winds over the northern Rockies, which could contribute to wildfires, and these winds will push the smoke over western Washington and Oregon. Will consider the situation carefully in the next blog.