Pearl Hill Fire, Northern Washington

Within the first 24 hours of the Pearl Hill Fire, it had grown to 174,000 acres, making it the 9th largest fire in Washington history with it continuing to grow over the next week. This fire was a bit unique as the Cold Springs fire merged with the Pearl Hill fire along the Columbia River. Since the fires merged, many look at them both as one complex, similar to the Okanogan or Carlton Complexes. Both fires combined burned 337,000 acres within the first two days, making it the largest fires in Washington history (Okanogan Complex from 2015 burned 304,782 acres). Both fires would continue to burn for the next several days. By the end of containment on September 17, both fires burned a combined total of 413,653 fires, surpassing the Okanogan Complex by 108,871 acres.

• September 7: Fire Reported
• September 8: 174,000 (Morning Estimate)
• September 9: 174,000 acres (Morning Estimate)
• September 10: 177,605 acres (Morning Estimate)
• September 11: 219,956 acres (Morning Estimate)
• September 12: 219,956 acres (Morning Estimate)
• September 13: 223,730 acres (Morning Estimate)
• September 14: 223,730 acres (Morning Estimate)
• September 15: 223,730 acres (Morning Estimate)
• September 16: Fire Contained

When looking at models, the farther out from an event, the higher the uncertainty is. NWS Spokane published a blog on September 3 indicating the potential for upcoming extreme fire concerns from September 7 to 9. You can find a link to the blog below.

After publishing the blog, the first fire weather watch was issued indicating that the chance was increasing for fire weather on September 4th. Below is the progression of Fire Weather Watches and Red Flag Warnings.

• September 4th at 2:14 PM PDT: Winds 15 to 25 mph with gusts to 40 mph with a relative humidity of 16% to 25%.
• September 5th at 5:33 AM PDT: Winds 15 to 25 mph with gusts to 45 mph with a relative humidity of 11% to 23%.
• September 5th at 3:08 PM PDT: Winds 20 to 30 mph with gusts to 45 mph with a relative humidity of 14% to 22%.

Looking above, you can see the changes that occurred even over a matter of 24 hours. The wind speeds were being raised while relative humidity was lowered. That was just the opposite of what they wanted to see.

24 hours prior to the start of the event, the Fire Weather Watch was upgraded to a Red Flag Warning.

• September 6th at 5:30 AM PDT: Winds 20 to 35 mph with gusts to 50 mph with a relative humidity of 12% to 22%.
• September 6th at 2:01 PM PDT: Winds 20 to 35 mph with gusts to 50 mph with a relative humidity of 12% to 22%.
• September 7th at 5:13 AM PDT: Winds 25 to 35 mph with gusts to 50 mph with a relative humidity of 10% to 19%.

At the bottom of each watch and warning, each product contained the impact "Rapid fire spread of any new or ongoing fires will be possible. Heed burn ban restrictions. Outdoor burning not recommended."

In addition to the Fire Weather Watches and Red Flag Warnings, Wind Advisories and Warnings were also issued for this same area. This combination of high winds and low relative humidity is detrimental to any area with active fires. At the bottom of each Wind Advisory and Warning, NWS Spokane provided specifics on the timing, which are listed below.

ADDITIONAL DETAILS...The strongest winds will come with the cold front and for several hours thereafter....from 8 am to 2 pm. Strong gusty winds will continue through the afternoon and then gradually decrease in the evening.

The fire broke out the morning of September 7 at roughly 3:39 AM PDT near Bridgeport, WA but the cause of the fire is still under investigation. The fire spread rapidly, reaching 8,000 acres by 9:45 AM with many level 3 evacuations in place. The number of level 3 evacuations were expected to continue to grow over the next few days as the fire exploded.

Steve Bodnar, a forecaster from NWS Spokane as well as an Incident Meteorologist (IMET) was at home on September 7 but he knew that there was a chance that he was going to be sent out to a fire. But until he knew he was going to be deployed to a fire, his main focus was on protecting his family and home. The "wet and cool Spring" that Spokane received caused the grass crop to grow thick and all the "fuels were extremely dry and dangerous." The main threat for his property was that the strong winds could cause a downed powerlines and the fire would spread rapidly which is why they packed the car up with the necessities just in case a fire started.

Luckily for us, we did not have any fires in the vicinity of our property. I was monitoring the fires ongoing in Central WA and knew that an IMET deployment was imminent for the next morning." - Steven Bodnar, Forecaster at NWS Spokane

Sure enough, by 6 PM PDT, Bodnar was on his way to the Pearl Hill Fire to help provide on site weather.

The winds continued to blow throughout the evening which can be viewed on a shortwave IR Band Satellite image, also known as a 3.9 μm. As long as conditions are clear, this channel helps forecasters view fires against the terrain. The white passing over Washington are thin clouds which allow the 3.9 channel to pick up the fire throughout the day.

As winds began to die down in the evening, fire planes were dispatched to help battle the blaze. They would only get a couple hours of retardant drops over the blaze before the sun began to set.

Douglas County Fire District, where the fire began, posted a few images of the fire at sunset.

KHQ, a local news station in Spokane, WA came out with an article at 9:15 AM the morning after the fire started stated that the fire has grown to more than 174,000 acres in 24 hours. That acreage is equivalent of 271.875 square miles!

Fire fighters were called in from many surrounding cities to help battle not only the Pearl Hill fire but the Cold Springs as well.

In Bridgeport, WA, those who have been allowed back into their homes on September 11 got the unfortunate notice that all water for consumption needed to be boiled. While specifics are unknown, the Pearl Hill Fire caused enough damage that the water within town was no longer safe to drink. This notice was rescinded on September 18.

Below is the final update from Northwest Interagency Coordination Center (NWCC). The final update is published when the fire is behind a containment line but interior pockets of fuel may continue to burn. This was also the final update due to the incoming rain and low pressure area expected to pass over the area which would decrease the threat of the fire continuing to spread.

Relief was brought to the area when all evacuation orders from the Pearl Hill Fire were lifted on September 17. It was then that those evacuated got to see what was left of their home. 50 properties were destroyed. Amazingly enough, for how quickly the fire spread, there were no injuries or fatalities reported

I was home during the wind event with my daughter. We had go packs ready to run out the door in the event we saw smoke and a plan to grab our animals. We live in a rural area of Spokane County northwest of town on acreage. The grass crop was thick from a wet and cool Spring. At this point, the fuels were extremely dry and flammable. You knew if a powerline came down nearby, there was no doubt that a fire would start and would spread rapidly. Luckily for us, we did not have any fires in the vicinity of our property. I was monitoring the fires ongoing in Central WA and knew that an IMET deployment was imminent for the next morning.

The Spokane office has a well established fire weather program. During fire season, we have daily live briefings with our partners. These are also recorded and posted to the webpage. We started to hit on this event from September 1st onward. We had a few marginal weak wind/rh events in Central WA Friday and Saturday on 5th and 6th and decided we would just elevate the messaging for these and really hit on the Labor Day Event. A fire weather watch was issued on 9/4 for the Labor Day event (9/7). This was upgraded to a red flag warning at 0500 on 9/6. Daily briefings were declaring this a critical fire weather day from September 3rd onward. (Sep 1-2 briefings were not archived so unclear on that messaging). The office also sent 1-pager partner emails starting 9/2-9/5. A live briefing was held for all otx partners (utility, EM, etc.) on 9/6 indicating a HIGH impact event.

Forecast panned out. Strong, damaging winds not only resulted in 16 new fires but widespread blowing dust and numerous road closures. WA DOT indicated this was the biggest road closure event in a single day with I-90, US 2, and US 395 all closed at the same time from dust and smoke. Winds gusted 44-50 were common with Sandpoint, ID hitting 54 mph. One employee did come to the office for 7 hours OT but given the pandemic, having extra bodies at the office was difficult. Several other employees assisted from home but I could not find the documented CTE/OT.