Dixie Fire Narrative

I started The Lookout in early August, 2021. This post is made up of content I posted about the Dixie Fire before The Lookout was established on the forums.wildfireintel.org website, where a bunch of us fire-geeks share intel during active wildfires.

7/14/21 – 8am

Looks like the VIIRS IR data is from about 2am.
Blue area is 2018 Camp Fire.

The whole area burned with mixed severity during 2008 BTU Lightning Complex – Light blue on this image.

 

7/14/21 9:45am

It’s a pretty bad setup. The lower atmosphere has cleared out in last few minutes, and the fire is stretching out a healthy column to the NW. It is going to spread fire way out in that direction with long-range spotting and the afternoon upslope winds and terrain are going to want to push it north.

Downslope winds tonight could push it SW toward Stirling City and inaccessible parts of Kimshew Creek Gorge.
Really liking the wind forecast, fire history, and heat detection layers in CalTopo. Great tool!
https://caltopo.com/map.html#ll=39.92961,-121.37728&z=13&b=f16a&o=r&n=0.3&a=fire%2Cmodis_mp%2Cwxd_wgust-06 109

 

7/14/21 5pm

13:00 VIIRS put it at about 1,800 acres.

Most of that was in areas that burned hot in 2008. Sounds like the lighter fuels are helping them out in tanker effectiveness, esp on the left flank.

 

7/15/21 6pm

It’s really exposed to the downcanyon winds, for sure.

 

7/15/21 12pm

Fire stayed farther east than I thought it would yesterday. It sounded on AirTac like the open canopy and rockiness in the 2008 burn area really helped the tankers get the west flank thoroughly painted. The head was really narrow.
The big question now seems to be where to tie in the north/eastern flanks. Looks like it has the alignment to continue to run up Rock Creek, though it will be in similar fuels as long as it stays in the 2008 burn (light blue). If it gets past Rock Creek (above the Rock Creek label on this map), it gets into the 2000 Storrie Burn, which reburned during the 2008 Butte Complex.
Either way, any fire that becomes established outside 2008 burn scar is going to move in a lot different fashion than what we have seen last 36 hours.

If the fire moves far enough upstream, it will be across from areas that didn’t burn last year in the Bear/North Complex, shown in purple. The SW edge of fire is bumping 2018 Camp Fire (blue)

7/15/21 9pm

On the Bald Mtn cam 68, it looks like the left flank has spilled out to the west of Rock Creek drainage and is well-established in the heavy brush and timber outside of the 2008 burn.

7/16/21 6:30am

Hard to tell if it left the 2008 burn or not on the west flank. The 8pm IR showed it still within, I think I was just seeing heat bleeding over the ridge on the IR cam view. The 5am Flea Mtn shot shows a lot of heat on the NW corner.
Biggest story on the 8pm IR is that it has slopped over Tobin Ridge into the 2000 Storrie Burn, above Storrie and Tobin.

One thing that I’m curious about today: There is an existing dozer line up the ridge on the NW corner of the fire, in Sections 11 and 14, above North Valley Creek at the 470U line, but it looks the the area all around burned in 2008, was replanted, and has recently been thinned. All of the red slash from the thinning is still on the ground in the imagery (red areas). I’m curious if this will cause any problems in holding this line. It looks like the gorge of North Valley Creek is a bad setup to funnel downcanyon winds, either way.

 

7/16/21 3:45pm

Looks like tankers are painting the slash-covered ridge I was talking about earlier.

Looks like the fire is still to the east in Rock Creek.

 

7/17/21 3pm

Looking at Flea cam, fire is cooking up hot in Rock Creek drainage. Helos were working hard in Div P to cool it down adjacent to the dozer line west of Creek Dip.

6:52 pm
The tankers are starting to paint the ridges well to the west of the primary dozer line in Division P. Can’t see in the cameras what’s going on there, and what the spread is like up the east side of that ridge, but the fire has been ripping hard up Rock Creek all day.

4:15 pm

It has alignment with slope, hot slopes, and upcanyon winds to really blast up the south side of Bald Eagle Mtn if it gets on that slope. Bald Eagle Mtn is little green icon east of Tobin on the map.
Here is a map showing location of 2020 Bear Fire.

5pm
Oldcdfguy
I am watching this thing blow up… in the last 15 minutes

 

6pm
Fire history map. Tankers are painting the ridge on Bald Eagle Mtn, which is the green icon, upper left of 1999 Bucks label.

9pm

Did I hear correctly that the primary dozerline in Division P got lost today?

7/19/21 6:40am

Last night’s 23:45 IR shows it pooching out over the bottom of the 2020 Bear Fire contingency dozer line in Division P. Was this a firing OP, or did it cross the line?

Another impressive column today

40 S/T Anytype all ordered CFAA mission on 3 digit request numbers(Not Fed Mission)
The notes say “prefer type 2,3,4,5,6.

The orders are being placed throughout the state

Oh yeah
3 more Limas on state mission
28 Doz type 2 on fed mission

There is not a lot of work for 40 strike teams of engines anywhere between Lake Almanor and Belden, but plenty of work when the fire gets there, or gets to Greenville or Meadow Valley. It could be a while, though. The Chips Fire, shown in blue and green in the Google Earth image below, got large because of lack of places to tie in fireline in the gnarliness of the North Fork Feather, coupled with spotting and a generally high resistance to control in the heavy fuel loads of the twelve year old Storrie Fire. I wouldn’t expect we are going to pick up this fire within a much smaller box than the Chips Fire on the north end.

It took almost 3 weeks for the Chips fire to get from Belden to the West Shore of Lake Almanor. 2012 was also a critically dry year, and the ERCs were in the 97th percentile. Read about Chips Fire behavior here 16:

 

Here is the 2pm VIIRS looking up the North Fork Feather. The base image is manipulated to show areas that burned hot in during the 2012 Chips Fire (blue/green outline) in pink.

 

Red Hill, from Kurt’s post, is in the center of this image. It is called that because of the weathered, rusty serpentine soils and rock. Not much grows there.

Notwithstanding the discussion below, Rush Creek (next canyon to east of Chips Fire footprint) stands out as a place the fire could continue its big push. It is aligned with the main Canyon of the Feather, and unlike the ground burned by the Chips Fire, it has no large fire history for the last 60 years. The Dixie Fire ran about 10 miles in 24 hrs on 7/18 and 7/19 with extreme instability in the atmosphere. Weather is forecast to gradually get drier and more stable, but tomorrow and Wednesday will still be unstable, though not as severe as last 2 days (thanks Julia Ruthford for excellent briefing 7 tonight).

100 years of fire history (or lack thereof) with 7/19/21 1400 VIIRs data. All of the historic fires in this area have run toward the NE.

 

Regarding the spread of the fire toward Lake Almanor: Many of us were worried the 2012 Chips Fire was going to blow straight up the North Fork Feather (Caribou, Seneca, Canyon Dam), and up Keddie Ridge/Dyer Mountain (right of East Shore label), but fires in the past here haven’t often run straight up the main canyons of the North Fork Feather River or East Branch (Feather River Canyon above Caribou Road). This year may be different, but in the past, fires in the deep canyons get some alignment in the afternoon and take out a side drainage where the upcanyon is blowing directly onto a solar slope. During Chips, we got a lot of backing and flanking fire in the time periods outside of the major runs, and that’s a big reason there are still a lot of trees on the slopes that are sheltered from this alignment. Areas that got these sort of aligned runs in 2012 are highlighted in pink on the second map, above. Haines index of 5 or 6 was a good predictor of major fire runs in the Chips Fire.

Obviously this is a long-haul fire, and how similar it behaves to Chips is an open question. It’s hard to tell how having all of the completely-exposed 9 year old brush and slash from dead trees in the Chips burn will affect rates of spread. But the portions of Chips that burned in the 12 year old Storrie Fire had similar fuels to what we’ll see in the Chips Burn, and topography and winds haven’t changed, so I expect we’ll see very similar localized runs based on daily weather patterns and periods of instability.

The flats south of Almanor have a lot of roads and large areas which were salvage logged and are very [open and cleaned up] (ALERTWildfire | Shasta Modoc 25). These things will keep the fire from running hard right at the Lake when it gets there.

The fire on the east side of Highway 70 is going to have some of the same factors at play. An important thing to consider on fires in these broken canyons (or in most canyons) is that at any given time, half of the landscape is out of alignment with the wind and sun. That’s why we often see only 50% of the landscape burning with high severity. The Bucks Fire was another long-hauler. On past large fires like the Bucks, Camp, or Bear, unless you have a long stretch of canyon exposed to the upcanyon wind (for example where the fire ripped above Rodgers Flat yesterday or toward Virgilia today) you just haven’t seen huge upcanyon runs, and things are driven more by rollout and slow flanking, with the occasional larger run up an aligned slope.

IR Map of fire spread above Tobin, 7/18/21, 23:45 hrs.

I came across the Chips Fire Behavior Report – hadn’t seen it before. Good reading for anyone headed to this fire. https://www.fs.fed.us/adaptivemanagement/reports/ChipsFireBehavior_Fullreport_16Jan13FINAL.pdf

More to come on this thread. View the whole thread here:

https://forums.wildfireintel.org/t/ca-btu-dixie/17564