Satellite-based sensors have become an important tool for determining the intensity of wildfires in real time.
And the latest satellite data shows that the Bolt Creek fire on US 2 near the Index has subsided significantly.
Many weather satellites have sensitivity radiation meter You can feel the heat emitted by the forest fire. The Bolt Creek Fire was indeed evident in satellite imagery over the weekend, but today there are no obvious signs of heat (see below). No orange/red dots.
Tonight’s infrared satellite image shows no black dot (black indicates warm temperatures in such an image).
The visible satellite image has an unobstructed view of the Bolt Fire area before sunset. There’s still some smoke (meaning some low-level burning remains), but nothing like it was a few days ago.
Conditions have become MUCH more favorable for extinguishing fires. Yesterday it rained a few times.
Importantly, the strong winter winds (from the east) that fueled the original fire have disappeared, replaced by weak winds from the west. The temperature has dropped sharply and the relative humidity has increased significantly.
To illustrate the dramatic changes, consider observations of a nearby fire weather site (the Johnson Ridge RAWS site at 2000 ft). Temperatures have dropped from nearly 90 degrees Fahrenheit on September 10 to 66 degrees today.
Relative humidity has gone from an amazingly low 15% to 90-100% today. Very convenient.
And the dead fuel moisture content of grass and small vegetation has increased from the highly flammable 6% to the relatively unburnt 20% today.
Temperatures should stay cool and skies should be cloudy for the next few days in the vicinity of the fire.
Finally, the latest air quality map shows good to fair air quality west of the Cascades, but with smoke to the east. Tomorrow will be similar, but expect improvement over inland regions on Wednesday. The worst thing is over everyone.
