Smoke in the West Means Relief in the East. The Big Threat Comes Later this Week

As predicted, the winds aloft have turned easterly (from the east), resulting in smoke from eastern Washington moving aloft over western Washington.

This is actually good news for eastern Washington, as it leads to reduced wildfire activity and eastward fire movement.

This situation is only temporary, and later this week the situation will reverse, again pushing strong westerly winds into eastern Washington... with the potential for renewed rapid fire growth.

The Seattle PanoCam shot at 7 AM was not subtle.  Lots of smoke.

And the visible satellite image clearly showed the smoke moving westward aloft:

Air quality is still relatively decent in most of western  Washington (green and yellow dots below), except for the western slopes of the Cascade Mountains

The fact that most of the smoke is aloft is shown by the laser ceilometers run by the Puget Sound Clean Air Agency (see the vertical plot over time at Seattle's Beacon Hill below).

Surface heating during the day shows mixing down some of he smoke later today, so surface air quality may decline.

The current pattern, with high pressure aloft over the eastern Pacific, is good for reducing winds in eastern Washington--which means less rapid fire growth (see max winds so far today below).

Less wind means less fire spread, which gives fire crews a chance to deal with the fires.

But there is a problem.    

As the upper-level ridge of high pressure moves inland (see forecast for Friday afternoon below), strong winds will push eastward down the eastern slopes of the Cascades

To illustrate, here is the surface wind gust prediction for Friday afternoon.  Not good.

Such winds will rev up the Little Giant Fire, which is the most serious fire of concern at this point

Finally, there is a lot of talk about this fire event having to do with climate change.  The Seattle Times and some current/past politicians have been particularly egregious about such claims.  

Such claims are demonstrably false, and I will examine this issue in detail in a future blog.

The fires were initiated by lightning and arson, neither of which is connected to climate change

Winds were critical, and they have no connection with climate change.

Fuel moistures were near normal before the fires, so all the drought and low snowpack claims are irrelevant.

Smoke and Fire During A Cold Wave

One of the most interesting aspects of the current smoke/fire event is that it is occurring during a cold wave.

Over the past few days, temperatures in eastern Washington have been well below normal.   

Not a heat wave associated with global warming.  A cold wave with strong winds.

Don't believe me?  Below are the daily low surface temperatures yesterday and today (only showing values of 40F and below).

My God! 

Several locations dropped into the mid-30s!  Since such temperatures are measured around 6 feet, the surface temperatures could have dropped to freezing!

Smoke and ice...what a combination.

The surface temperature analysis for Sunday at 4 PM shows the very cold temperatures over the northwest.  Burr.....

Temperatures aloft were also very cold.  

Here are plots of Sunday and Monday morning temperatures around 5000 ft (850 hPa pressure).  Blue is colder than normal.

The cold and winds (which produced the rapid fire growth) are connected, both associated with a strong upper-level trough of low pressure moving through this weekend (see map at 500 hPa, about 18,000 ft below).  

Blue shows heights below normal (a trough).

Currently, air quality is good in western Washington, with any smoke staying aloft, moderate in the Willamette Valley, and poor in eastern Washington (see below).

The forecast surface smoke (NOAA HRRR Smoke model) for 11 PM tonight is good for western Washington, unchanged for the rest of the region.  Really bad near the Little Giant Fire near Lake Chelan.