Although there are very few wildfires in Washington, Oregon, California and southern British Columbia, there are still severe fires in the northern Canadian forests of northern British Columbia and Alberta.
And that smoke will rise high above Washington State tomorrow and Tuesday.
Below is a map of the current wildfires in Canada. Large red dots indicate current active large fires.
The problem for the Pacific Northwest is that an upper band of high pressure will develop offshore, with a trench inland, resulting in strong northerly winds that provide a rapid path for smoke from the northern Canadian forests.
500-hPa (approximately 18,000 ft) map for Monday at 5 a.m.
The NOAA HRRR-Smoke model provides ingenious forecasts of wildfire smoke. Let me show you what it predicts.
At 9 a.m. Monday, moderate smoke entered Washington State overhead
A day later, denser smoke will rise high in our area. The sky will lose the blue color of the past days.
Most smoke from distant sources is usually overhead, but if the plume is low enough, some smoke can mix with the surface on warm days.
Here’s a vertical cross-section of the smoke at 11 p.m. Monday night. Most were still aloft at the time.
But Tuesday’s dramatic warming (where temperatures will rise in the mid-80s) will mix some of it down to the surface (see cross-section at 5 p.m. Tuesday).
Surface air quality ALWAYS drops on July 4th due to all the fireworks. This year the miasma will be “enhanced” by smoke from British Columbia.
The good news is that the upper flow will change (more westerly) on Thursday and will sweep the smoke out of our area.
As will be discussed in a future blog, the latest forecasts keep our temperatures moderate, winds low and the likelihood of wildfires moderate.
Also: Here is a satellite image visible at 6:41 a.m. Monday, clearly showing Canadian smoke moving south into Washington State:
