143-mph 'fire tornado' that cut a path of
destruction is an ominous sign of the future
By RONG-GONG LIN II , JOSEPH SERNA and LOUIS
SAHAGUN
AUG 03, 2018 | 8:55 AM
| REDDING
As authorities sifted the rubble from the fire that
burned more than 1,000 residences in Shasta County,
they were startled by what they encountered.
A soaring transmission tower was tipped over. Tiles
were torn off the roofs of homes. Massive trees were
uprooted. Vehicles were moved. In one spot, a fence
post was bent around a tree, with the bark on one
side sheared off.
This was not typical wildfire damage. Rather, it was
strong evidence of a giant, powerful spinning vortex
that accompanied the Carr fire on July 26. The
tornado-like condition, lasting an hour and a half
and fueled by extreme heat and intensely dry brush
as California heats up to record levels, was
captured in dramatic videos that have come to
symbolize the destructive power of what is now
California’s sixth-most destructive fire.
It may take years before scientists come to a
consensus on what to exactly call this vortex — a
fire whirl, as named by the National Weather
Service, or a fire tornado. Whatever it’s called,
it’s exceptionally rare to see a well-documented
fire-fueled vortex leap out of a wildfire and enter
a populated area with such size, power and duration.
“Depending on the final number, this might actually
be the strongest ‘tornado’ in California history,
even if it wasn’t formally a tornado,” UCLA climate
scientist Daniel Swain said by email. There have
been a couple of marginal EF-3 twisters in
California’s past, “but this fire whirl was almost
certainly longer-lived, larger in spatial scope and
perhaps even stronger from a wind speed
perspective.”
The vortex could be a factor in the deadly ferocity
of this blaze, which killed six. And with climate
change playing a factor as California enters a
worsening era of wildland fires, last week’s fire
vortex adds a layer of unpredictability and danger.
“Not all big fires are going to result in these big
fire whirls, even in a future that’s much hotter and
drier,” Swain said. “This won’t be the primary risk
associated with wildfire, ever. But under the right
atmospheric conditions, all else being equal, the
increasing intensity of fires themselves will play a
role in producing these localized fire weather
conditions that can be quite extreme.”
Radar analyzed by Lareau clearly shows a spinning
vortex in northwest Redding as the Carr fire rapidly
expanded in the evening of July 26.
Lareau roughly estimated the vortex as being as
perhaps 500 yards in diameter at its base before
possibly contracting. “It’s covering blocks,” he
said.
“It was definitely a massive one, and that just
speaks to how intense the heating was,” said
National Weather Service meteorologist Mike
Kochasic. “It created such a massive whirl that it
looked like a tornado … and it takes an impressive
amount of heating and local wind swirling up to
create something like that. It was quite a monster.”
It’s possible for fire vortexes to “move fairly
quick out in front of the main line of the fire — it
can spread a little bit quicker compared to the main
fire,” Kochasic said.
Wind damage was also reported in areas untouched by
flames.
A team of officials led by the California Department
of Forestry and Fire Protection is looking into the
vortex as part of its investigation of the blaze.
This vortex is dramatically different from the
garden-variety whirls that have been more of a
curiosity in past fires, which are more like dust
devils in terms of scale, rising for perhaps two
stories and lasting for less than 10 minutes.
Lareau’s radar data show that one of the worst-hit
areas was on Quartz Hill Road, around a Y-shaped
junction of electric transmission lines — a matter
of hundreds of feet from where Melody Bledsoe, 70,
and her great-grandchildren, Emily, 4, and James
Roberts, 5, died as the fire swept through their
home.
Half a mile west from the Bledsoes’ home is Lake
Keswick Estates, where Justin Sanchez, 37, fled in
the back of a pickup truck, with irreplaceable
photos lining its bed, as his father, Greg, 69,
drove them away from what he called a fire tornado.
(* Youtube of driving away from fire tornado:
https://www.youtube.com/watch?
time_continue=75&v=bRWyoOqLkY4 )
“It was like the movie ‘Twister,’” Sanchez said in a
telephone interview. “It was a massive, massive,
huge tornado …. it was spinning so slow on the
outside, but there were heavy, massive pieces of
shrapnel just floating around with the fire.”
Sanchez said that earlier that day he could see the
blaze, but it wasn’t traveling particularly fast.
Then he heard his neighbor shout, “It just jumped
the river! It’s headed our way!”
“Within a matter of 10 minutes there, once the
‘fire-nado’ started almost inching on our
neighborhood, the winds had to have been 40 to 60
mph winds … the sky got dark,” Sanchez said. “I
didn’t understand how a fire and tornado could
combine into one massive death machine.”
He said he dashed into the house a couple of times
to grab some photos, but the second time he came
out, the fire had come probably within a football
field away. Sanchez said the vortex traveled three
to four miles in just 15 minutes.
A late gust was so intense that the last keepsakes
he nabbed were blown out of his arms.
“I knew everything was going to become lost, and it
was going to end up killing people on the way. It
was nothing like I’ve ever seen or heard of in my
life,” he said.
As Redding Police Chief Roger Moore evacuated
residents from the River Ridge neighborhood east of
the Sacramento River, he watched the growing flames
and smoke plume approach the western bank of the
Sacramento River, hop over it, grow, then come
together as what he called a “plume tornado.”
Trees appeared to be levitating, and branches and
sheet-metal roofs seemed to orbit the column, Moore
said. Uprooted objects launched into the air ignited
mid-flight. Vegetation and homes hundreds of feet
from the column also caught fire before the twister
arrived, he said. It was as loud as a roaring jet
engine.
“Wherever the center of the tornado went, it
decimated it. You’re looking at this whole column of
fire and it’s just monstrous,” Moore said. The swirl
of fire and smoke destroyed sections of the Stanford
Manor community. “The only things left standing were
the homes on the edges. Some would ignite; some
would remain standing.
“I don’t know how fast that tornado was moving, but
it was probably faster than a human can run,” Moore
said.
Spinning vortexes of fire can be deadly, whether
they’re called a fire tornado or a fire whirl.
What’s common in both is that they are driven by an
exceptional amount of heat being released into the
air — heat probably fueled by record or near-record
vegetation dryness caused by the state’s
persistently high temperatures.
Other factors are important, though, said Craig
Clements, an associate professor and director of the
Fire Weather Research Laboratory at San Jose State
University. “It’s really too early to tell what
caused it, and there still needs to be a lot of
scientific investigation.”
The rising heat can reach 130 mph, Lareau said, send
smoke up beyond its normal limit of about 15,000
feet and form its own fire-fueled cumulus cloud,
rising to as high as 39,000 feet. The creation of
the puffy cloud means that more heat is being dumped
into the column of hot, rising air. That air is
replaced by winds rushing in all around the chimney
of rising air.
The lowest part of the vortex often takes an orange
glow from combusting gases rising within its core,
according to a 2012 study by the U.S. Forest
Service. Fire whirls can range from less than 4 feet
to as large as 1.9 miles in diameter, the study
said, and are especially a safety hazard by
increasing fire intensity, triggering spot fires
from burning debris floating from the vortex, and
causing an unpredictable mix in the speed and
direction of the fire.
In 2008, a whirl caught firefighters by surprise in
the remote Indians fire that burned in extremely dry
chaparral in the Los Padres National Forest, causing
serious injuries and forcing the deployment of fire
shelters.
The only well-documented case of a true fire tornado
hitting a populated area came after years of study
of the 2003 Canberra wildfires in Australia, in
which scientists said the tornado lifted off along
its track — making it distinct from a fire whirl.
That fire tornado lifted up an 8-ton firetruck and
also picked up a 2-ton police car and dropped it
into a stormwater drain; its beacons and external
attachments were stripped by strong winds. On one
street, some homes were destroyed by fire, while
others suffered only wind damage.
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