Wind and Fireworks Brings A Fast-Growing Wildfire Near Lake Chelan

 The  Chelan Hills fire, reported to have been started by some irresponsible fireworks Saturday morning, has now spread to over 10,000 acres (see map below).

A high-resolution visible satellite image this morning shows the burnt area (dark color), and the satellite imagery shows some still-active fires (red dots).  Smoke from  another (smaller) fire is apparent to the southwest.

The fire started in grass and range vegetation, not forest.  

Importantly, this vegetation was NOT unusually dry, as shown in the figure below, which provides 100-h fuel moisture levels on the eastern slopes of the Cascades.  Red is observed moisture level, and the shading shows the normal range.  

Current moisture levels were above normal.

So "climate change" can not be blamed.

What can be blamed was strong winds.  

Winds that were skillfully forecast by the UW WRF modeling system and the NOAA models.  To illustrate, below is the wind forecast for Saturday afteroon be the UW WRF weather model....strong winds were predicted around Chelan!

Below are the strongest observed winds yesterday around the fire area.  A 36 mph gust was observed near the fire start.

Winds at this location really revved up during the afternoon and early evening (see below).

At the same time, relative humidity plummeted to less than 20%--the result of drying of air moving downslope on the eastern side of the Cascades.

There is reason that wildfire starts are maximized on July 4th.  

The ignitions are there, the grasses/range vegetation are dry enough to burn, and it is early enough in the summer so that strong onshore flow produces powerful winds.

How Much Has Global Warming Changed July 4th Temperatures Over Washington State?

Walking my dog yesterday, I ran into a neighbor who asked whether July 4th temperatures in our area had changed much under global warming. 

I promised to run the numbers... and here are the results.  

Be prepared to be surprised 😀.

Starting at Olympia, on the western side of the state, there is almost no trend in July 4 daily average temperatures since the 1940s! (The purple line is the linear trend).

What about the highest temperatures each year on July 4 in Olympia?   

No trend!  

OK, now let's check Yakima in eastern Washington! 

The July 4 average temperature trend is slightly upward (a little less than 2 F over 75 years).

The trend in the maximum temperatures at Yakima is similar.  Modest upward increase.

And then there is Spokane, over the northeast side of Washington (below).  Very little trend in average July 4th temperatures or in the highest temperatures on that date.

What about precipitation on July 4th in Olympia?  As shown below, there is little evidence of a long-term trend.

Anyway,  a big yawn is appropriate for the July 4 trends in temperature over Washington State.

The planet is slowly warming for sure, but the temperature trends in Washington State are very, very modest.

But you might get a different answer if you relied on AI.  

I asked Google's AI to create a graphic summarizing the July 4 temperature trend over Washington.

It created the graphic below, with a dramatic upward trend over Washington from 26F to 80°F since 1990 (below).  Was it really below freezing in July in 1990?

Total nonsense.