Researcher uses radar data to make three-dimensional maps of smoke plumes
Radar rendering of smoke plume over the Creek Fire. By Neil Lareau, University of Nevada Reno.
The extreme heat caused by a large high pressure system in the West has led to an unusual number of fire tornados.
An article in the Washington Post by Matthew Cappucci explains how Neil Lareau, a professor of atmospheric sciences in the department of physics at the University of Nevada at Reno, used detailed weather radar data to make three-dimensional maps of smoke plumes over fires. While it is unusual to have a fire tornado anytime, the data indicates that on at least three fires this year fire tornados have been detected by radar. One was photographed on the Loyalton Fire August 15 about 12 miles northwest of Reno, Nevada. National Weather Service meteorologists who spotted it on radar issued the agency’s first-ever fire tornado warning.
Fire tornado on the Loyalton Fire, by @DVRockJockey August 15, 2020.
Fire tornados and huge smoke plumes topped by massive pyrocumulus clouds are indicators of extreme fire behavior. There is absolutely nothing firefighters or aircraft can do to slow a blaze under those conditions — and those pyrocumulus clouds seem to be occurring more frequently this year.
Creek Fire September 5, 2020. IMT photo.
The day after the Creek Fire started, its smoke plume grew to 55,000 feet, taller than the tornadic thunderstorms seen in Oklahoma and Kansas in the the spring.
From the Post:
“Anecdotally, this is the deepest that I’ve seen,” said Lareau, who was shocked by the height achieved by the smoke plume. “It’s about a solid 10,000 feet higher than we’re typically seeing with the highest of these plumes.”
Before 2020, only a few fires had ever produced documented fire tornadoes in the United States; now we’re seeing them every week or two. Lareau says the tremendous heights of the wildfires’ clouds, combined with more concerted and astute observation, are factors in the numerous fire tornadoes that have been reported this year. He thinks there may also be some truth to the apparent increase.
“We have a ton of eyes on every fire, looking at every frame, but still, we weren’t seeing these before,” he said. “And we’re seeing all too much of it right now. It’s rather worrying.”
The red line was the perimeter of the Loyalton Fire at 4:30 p.m. PDT August 16, 2020. The white line was the perimeter at 2:19 a.m. August 16, 2020.
The map above was updated using data from a fixed wing mapping flight over the Loyalton Fire Sunday afternoon at 4:30. It is more accurate than the map below from an earlier flight that was supplemented with the red dots representing heat detected by a satellite. That flight plus data collected later by other means determined the fire had burned 36,295 acres
August 16, 2020 | 7:02 p.m. PDT
The red line was the perimeter of the Loyalton Fire at 2:19 a.m. PDT August 16, 2020. The red dots represent heat detected by a satellite at 2:48 p.m. PDT August 16, 2020.
The Loyalton Fire in northeast California 12 miles northwest of Reno, Nevada started at about 4:30 p.m. August 14 east of Loyalton, California. It burned north and east adjacent to the areas of Beckwourth Pass and Hallelujah Junction. Early Sunday morning a mapping flight calculated it had burned 29,829 acres. That was confirmed later in the day by the Tahoe National Forest.
Sunday afternoon it was pushed to the east and southeast by an 8 to 15 mph wind out of the northwest and was approaching the Nevada border at 2:48 P.M. MDT.
On August 15 meteorologists with the National Weather Service in Reno observed on radar a very rare fire tornado in real time at the Loyalton Fire about 12 miles northwest of the city. They used emergency warning systems to transmit tornado warnings as quickly as possible to firefighters and the general public. It is believed that this is the first time a real time warning for a fire tornado has ever happened, at least in the United States. More information about this very unusual event is at Wildfire Today.
“LOYALTON FIRE #LoyaltonFire
ROAD CLOSURE AND EVACUATIONS
State Route 70 is now open to thru traffic. Please continue to use caution due to first responders working in the area. US 395 is now open without restrictions. Please continue to use caution due to first responders working in the area.
A Mandatory Evacuation Order has been lifted for residents from US 395 at Red Rock Road south to US 395 at State Route 70.
A Mandatory Evacuation Order has been downgraded to an Evacuation Warning for residents along roads accessed by State Route 70 on the north and south side of State Route 70.
A Mandatory Evacuation Order has been downgraded to an Evacuation Warning for residents from the intersection of State Route 49 and 70 east to State Route 70 and US 395. US 395 south to the Sierra County line. This encompasses everything south of State Route 70 and west of US 395.”
At least five tornado-strength/scale vortices are likely to have occurred in the fire Saturday
August 16, 2020 | 5:04 p.m. PDT
Fire tornado on the Loyalton Fire, by @DVRockJockey August 15, 2020.
On August 15 meteorologists with the National Weather Service in Reno observed on radar a very rare fire tornado in real time at the Loyalton Fire about 12 miles northwest of the city. They used emergency warning systems to get the word out as quickly as possible to firefighters and the general public. It is believed that this is the first time a real time warning for this type of event has ever happened, at least in the United States.
They also sent out tweets, of course:
Map of the Loyalton Fire the morning of August 16, 2020, time uncertain, but possibly about 2 a.m.
The Loyalton Fire started at about 4:30 p.m. August 14 east of the town of Loyalton and southwest of Mount Ina Coolbrith. It burned north and east adjacent to the areas of Beckwourth Pass and Hallelujah Junction. Early Sunday morning it was estimated at 29,829 acres. More information about the Loyalton fire on Wildfire Today.
A fire tornado is just like it sounds — a large column of rotating air over a vegetation fire. Inside it and around it are extremely strong winds, very high temperatures, and flying debris.
On July 26, 2018 a firefighter was killed as a fire tornado burned and scoured a mile-long path as the Carr Fire moved into Redding, California. A Redding Fire Department Inspector was burned over in his truck and died on Buenaventura Boulevard. Three dozer operators were entrapped and one of them was also killed.
According to a Green Sheet report by CAL FIRE the conditions that resulted in the entrapment of three dozers and the Redding Fire Department Fire Inspector that day were due to the fire tornado — a large rotating fire plume that was roughly 1,000 feet in diameter. The winds at the base were 136-165 mph (EF-3 tornado strength), as indicated by wind damage to large oak trees, scouring of the ground surface, damage to roofs of houses, and lofting of large steel power line support towers, vehicles, and a steel marine shipping container. Multiple fire vehicles had their windows blown out and their bodies damaged by flying debris.
The strong winds caused the fire to burn all live vegetation less than 1 inch in diameter. Peak temperatures likely exceeded 2,700 °F.
Here is an excerpt from an article in the Washington Post about the fire tornados yesterday:
Fire tornadoes in and of themselves are rare; being able to detect them in real time on radar is something new. Wendell Hohmann is the meteorologist at the Reno office who issued the precedent-setting warning. He described it as a “once-in-a-lifetime, career event.”
“We were just trying to get the message out of the extreme fire behavior from this fire given the rotation and the tornadic potential,” Hohmann said. “We figured we could do a severe [thunderstorm warning], but we decided to do a tornado warning to get [the emergency alert system] and [wireless emergency alerts] to activate.”
Matthew Cappucci believes at least five tornado-strength/vortices are likely to have occurred on the Loyalton Fire August 15.
For those wondering about the #FireTornado that occurred in #California earlier on, here’s a brief explainer about what the heck happened.
The news media sometimes calls any little fire whirl a “fire tornado”, or even a “firenado”. These and related terms (except for “firenado”) were, if not founded, at least documented and defined in 1978 by a researcher for the National Weather Service in Missoula, David W. Goens. He grouped fire whirls into four classes:
Fire Devils. They are a natural part of fire turbulence with little influence on fire behavior or spread. They are usually on the order of 3 to 33 feet in diameter and have rotational velocities less than 22 MPH.
Fire Whirls. A meld of the fire, topograph, and meteorological factors. These play a significant role in fire spread and hazard to control personnel. The average size of this class is usually 33 to 100 feet, with rotational velocities of 22 to 67 MPH.
Fire Tornadoes. These systems begin to dominate the large scale fire dynamics. They lead to extreme hazard and control problems. In size, they average 100 to 1,000 feet in diameter and have rotational velocities up to 90 MPH.
Fire Storm. Fire behavior is extremely violent. Diameters have been observed to be from 1,000 to 10,000 feet and winds estimated in excess of 110 MPH. This is a rare phenomenon and hopefully one that is so unlikely in the forest environment that it can be disregarded.”
It was just two days ago that I wrote extreme fire behavior and massive pyrocumulus are becoming much more frequent. If we are going to see more fire tornados, that is a scary thought. The west coast is expected to have very high temperatures this week.
Is it just me, or recently have there been more wildfires than usual exhibiting extreme fire behavior and with MASSIVE pyrocumulus. It only took the #LakeFire 29 minutes from its first report. Some will say the increase started 15-20 years ago. But lately, wow!
