August Complex, Northern California

Up until the end of 2020, the Mendocino Complex was the largest fire in California history. That would be smashed by the August Complex by over double the amount of acres burned. The Mendocino Complex burned 459,123 acres while the August Complex would burn 1,032,649 acres by its containment date on November 12, 2020.

Beetle killed trees play a huge role in the explosiveness of wildfires. In the case of the August Complex burned a total of 1,032,648 acres across the Mendocino National Forest (612,000 acres), Six Rivers National Forest (162,000 acres), and the Shasta-Trinity National Forest (140,000 acres). In 2019, the USDA did a fly over aerial survey to estimate the number of dead trees. According to the  report from USDA , The results showed that 510,000 dead trees were found in the Mendocino National Forest, 474,000 dead trees in the Six River National Forest, and 1,348,000 dead trees in the Shasta-Trinity National Forest. To learn more about beetle killed trees, view the write up from the US Forest Service below.

After years of significant drought, the last few years of additional moisture allowed for most of California to be relieved from any drought. If you use the slider below, you can see the difference that 8 months make as the location of the fire is now in a severe drought.

• August 16: Fire Reported
• August 17: 1,000 acres (Evening Estimate)
• August 18: 3,025 acres (Evening Estimate)
• August 19: 65,030 acres (Evening Estimate)
• August 20: 116,372 acres (Afternoon Estimate)
• August 21: 117,365 acres (Morning Estimate)
• August 22: 150,000 acres (Morning Estimate)
• August 23: 160,005 acres (Morning Estimate)
• August 24: 177,750 acres (Morning Estimate)
• ...
• November 15: 1,032,648 acres (100% Contained)

The NWS Eureka office had on and off Red Flag Warnings for much of the area throughout the month of August. A Red Flag Warning was issued for the area of the fire from August 16, 5AM to 8PM for fast moving thunderstorms and erratic winds.

As October 21st approached, the NWS Eureka office began to ramp up messaging 24 hours in advance due to increasing winds and low humidity levels. This included the following.

• August 14th at 10:38 PM MDT: Fire Weather Watch issued for Fire Weather Zone 212, 277, and 279 for August 16th. Fast moving thunderstorms will pose a threat for fire starts due to lightning. Erratic gusty winds will be possible in and around outflow boundaries. Any fires that develop will likely spread rapidly. Outdoor burning is not recommended.
• August 15th at 11:22 AM MDT: Red Flag Warning issued for Fire Weather Zone 212, 277, 279, and 283 for August 16th. Fast moving thunderstorms will pose a threat for fire starts due to lightning. Erratic, gusty outflow winds will be possible in and around thunderstorms. Outside of thunderstorms, West to southwest winds will develop for Sunday afternoon and evening at 8 to 15 mph. Winds may be locally gusty through exposed river valleys and over mountain ridges. Lighter winds forecast for Sunday night and Monday. Higher potential for wildfire starts in proximity to thunderstorms due to lightning. Any fires that develop may spread rapidly due to the combination of dry fuels, low humidity, and locally breezy conditions. Outdoor burning is not recommended.

Red Flags Warnings were in effect on August 16th as dry lightning moved over the area. It was the waiting game to see how many fires would start. 37 fires would start on August 16th.

Additional thunderstorms would move over Northern California with erratic, gusty winds that would aid the spread of any fires along with new ones.

Fires grew to several thousand acres within the first 24 hours in areas with an extensive amount of dead trees which would only fuel the fire.

Conditions began to deteriorate more on August 19th with gusty winds and extremely low relative humidity. Those conditions were expected to last for days to even weeks with a few days of lulled weather in between.

Large pieces of ash fell from the sky in Orland, California on August 19th as the fires activity continued to increase.

The August Complex grew from 65,030 acres to 116,000 acres overnight as winds increased and relative humidity levels dropped with poor overnight recoveries. NWS Eureka showed an image from the 3.9μm Shortwave Window Infrared Band (Channel 7) which allows forecasters to view fire hot spots as long as conditions are clear.

The first buildings were destroyed on August 22 as the fire continued to grow. Firefighters were still working on gaining a perimeter.

While wind is important, both FBANs noted (using Fire Family Plus and their Fire Behavior program) that on days that experienced significant fire growth, the low RH was the primary factor with wind being somewhat secondary." - Lamont Bain (NWS Forecaster and IMET at Fort Worth/Dallas)

Additional thunderstorms moved over the area on August 23rd and NWS Eureka did their best to message the potential for rapid fire growth as gusty and erratic winds moved over the fires.

Many counties have adopted their own services for alerting the public of danger such as Humboldt ALERT or CodeRED. Make sure that you know what services your county provides so that you can stay up to date. Emergency Managers don't always contact their local NWS office asking for them to issue a Civil Emergency Message (CEM) which when one is issued, phones, TVs and radios all play the message. Always have multiple ways to receive notifications about evacuations.

The August Complex was 117,750 acres on August 24th with 11% containment.

The first and only fatality occurred on August 31st which was confirmed at a later date to be Diana Jones, 63, from Texas who was fighting the fire with her son. The winds ended up changing direction and the fire turned, consuming the truck.

The weather continued to be dry and breezy over the last month with the fire continuing to grow each day. On October 5th, the August Complex crossed over one million acres, making it the first gigafire in California history which is larger than Rhode Island

Recovery efforts began in early April to clean up the million acre fire. The Complex burned more than 612,000 acres of the forest's 913,000 acres. Despite the significant acreage that the fire burned, only 935 buildings were destroyed due to the remote location of the fire.

The days went by quickly as I was learning a lot while also performing the IMET duties. The high variability of the terrain, vegetation and weather was really neat to see. While we anticipated strong winds with the East Wind event, it ended up not being as high of an impact for our fire (due largely to sheltering). The "wow" factor, was still high, however, as we saw several new fire starts quickly get out of hand on the visible satellite imagery.

Leading up to the East Wind event, it was eye opening to see how quickly the operations and planning section really got things together (building new and maintaining lines, moving people around and getting them to spike camps. From a meteorology standpoint, I grew to understand how much sheltering can influence the magnitude of winds experienced at a given location. This is something that will always be in the forefront of my mind when trying to anticipate big events.

Another big takeaway was the importance of RH. While wind is important, both FBANs noted (using Fire Family Plus and their Fire Behavior program) that on days that experienced significant fire growth, the low RH was the primary factor with wind being somewhat secondary. I'd like to see more evidence of this, however, but this seems to be pretty powerful knowledge and I was fortunate to work with FBANs that really looked into that part of the fire behavior and thus impact to the overall IMT.