Researchers at Embry-Riddle Aeronautical University have published the results of their work which show that winds out of a thunderstorm affected the Yarnell Hill Fire. On June 30, 2013 at about 4:45 p.m. local time 19 members of the Granite Mountain Hotshots were killed as the fire changed direction and overran their position.
The weather that led to the fatalities has been clear since we covered it on Wildfire Today about three hours after the burnover before the entrapment was officially confirmed:
…This was apparently caused by a 180-degree shift in the direction of the wind. From 10 a.m. until 4 p.m. local time at the Stanton RAWS weather station four miles south of the fire, the wind was from the south-southwest or southwest, but at 5 p.m. it began blowing from the north-northeast at 22 to 26 mph gusting up to 43 mph. This may have pushed the fire into the town.
If there were any firefighters on the south or southwest side of the fire between 4 and 5 p.m., who previously had the wind at their backs for seven hours with the fire moving away from them, they may have suddenly and unexpectedly found the fire heading toward them at a rapid rate. Wind direction changes like this are sometimes caused by a passing thunderstorm with strong outflowing downdrafts.
And a few minutes later:
The radar map above from WeatherUnderground shows a thunderstorm cell north and northeast of the fire at Yarnell, Arizona. The pointer is at Yarnell. The cell was moving toward the southwest, and may have produced strong winds that changed the wind direction by 180 degrees and could have been part of the reason the fire moved into Yarnell. It also could have caught firefighters by surprise.
In 2014 an animation of the weather event was developed by Janice Coen, Ph.D., a Project Scientist at the National Center for Atmospheric Research in Boulder, Colorado. It simulates through a coupled weather-wildland fire environment model the spread of the Yarnell Hill Fire and the wind direction and speed. The arrows indicate the wind direction; the length of the arrows varies with the wind speed.
Below is a summary written by Ginger Pinholster, of the recent research conducted at Embry-Riddle Aeronautical University about the event.
Nineteen firefighters who lost their lives in Arizona’s 2013 Yarnell Hill fire were likely victims of the same meteorological event that caused a deadly 1985 airplane crash, Embry-Riddle Aeronautical University researchers have reported.
City of Prescott firefighters who were members of the Granite Mountain Hotshots were probably surprised by a sudden microburst during the Yarnell Hill fire, according to Embry-Riddle meteorologists Curtis N. James and Michael Kaplan.
A microburst, and the wind shear induced by it, was also what sent a commercial airliner careening off the runway at Dallas/Fort Worth International Airport, killing 137 people on Aug. 2, 1985. That accident prompted major improvements in aviation safety. The National Transportation Safety Board concluded that there had been no way for the L-1011 aircraft to detect microbursts and wind changes. In response, NASA researchers developed new warning technology, and the U.S. Federal Aviation Administration required all commercial aircraft to have on-board wind shear detection systems.
Firefighters do not yet have equivalent protections.
Although microbursts can be detected by Doppler weather radar scanning right above the ground, radar signals are blocked over mountainous terrain or in remote areas where wildfires occur. With funding from the National Science Foundation, James and Kaplan have been collaborating with researchers and graduate students at North Carolina A&T University as well as the National Weather Service to better understand and learn from the tragedy of the Yarnell Hill fire.
On June 30, 2013, “Firefighters knew about the squall line over the Bradshaw Mountains and its outflow moving toward Yarnell,” said James, professor of Meteorology on Embry-Riddle’s Prescott Campus. “What they weren’t anticipating was that a storm cell would develop and create a microburst just to the east of Yarnell. We think the outflow from that microburst rushed westward toward the fire, which then redirected the fire’s motion.”
Microbursts can form very quickly around the periphery of larger, previously identified storms, explained Kaplan, an Embry-Riddle adjunct faculty member and professor emeritus with the Desert Research Institute. “When they hit the ground, microbursts barrel outward, often at high speeds,” added Kaplan, who worked on a team that studied the 1985 crash of Delta Air Lines Flight 191 in Texas.
The Yarnell Hill fire, ignited by lightning amid a drought and extreme summer temperatures, turned in response to the microburst outflow. The fire then rapidly and unexpectedly advanced on the firefighters as they were trying to make their way to safety through a ravine, James said. Analysis of historical meteorological data showed that wind on the north side of the fire, at the Emergency Operations Center, was moving from the north-northeast at 13 miles per hour (mph), whereas in Stanton, southeast of the fire, the wind was gusting to 47 mph.
“It was a very different situation on the south side versus the north side of the fire,” James noted. “Fine-scale convective storm cells can create that type of variability in the wind. That’s something the firefighters weren’t anticipating.”
Staying Safe on the Front Lines
First responders should have access to more information about microbursts, the Embry-Riddle researchers said. Even as an initial thunderstorm may seem to be waning, “It may spawn new storm cells that are extremely focused and intense, and incredibly small sometimes, yet they can wreak havoc,” Kaplan said.
To help raise awareness of the risks of microbursts, James and Kaplan recently shared their findings at the Annual Meeting of the American Meteorological Society. The work has also been published by the journal Climate and the journal Atmosphere.
The next step for the research, Kaplan said, is to run higher-resolution model simulations coupled with a fire behavior model. If all goes well, this “forensic meteorology” approach will show the motion of the fire as it moved through the complex terrain toward the firefighters at Yarnell Hill. At a resolution of 50 meters, “That would get us pretty close to the scale of what the firefighters actually saw that day,” Kaplan said. “That’s our goal.”
In addition to James and Kaplan, the research team includes Mark R. Sinclair, of Embry-Riddle; North Carolina A&T State University researcher Yuh-Lang Lin and his graduate students; and Andrew A. Taylor of the National Weather Service. The research involved the use of the Cheyenne supercomputer at the National Center for Atmospheric Research and is funded by the National Science Foundation.
Thanks and a tip of the hat go out to Darrell.
No, not JB. Lol. Before that. But anyway… I was agreeing with your March 16 post. A Hotshot leader made an error with tragic and devastating consequences.
37 Years, Old ECHS…..JB….?
There is no cover up, I just believe that there are those that know what happened and just can’t talk about it……
There will never be a time that we do not repeat our history, that’s just part of the human condition, we just forget our history and step in big dung heaps, case in point look at whats occurring in Europe, Hitler is not old history, and here comes another tyrant hell bent on domination and genocide, hang on because it’s going to get a lot worse…..a lot….
Just look back at Man Gulch and all of the tragedy fires since, a great many have commonalities with one another, , Loop, Storm King, we just need to remember and apply our own history, once we do we will see a real decrease in these senseless deadly fires….Not rocket science…..
Unfamiliar with local factors influencing fire behavior…… o wait this was in their IA. Marsh knew that every afternoon there were outflows from the north….
We all push the limit when it’s our own dirt I get it, but we still have to get back to the basics
I was at the DFW Airport on Aug. 2, 1985. I remember Delta-191 falling out of the sky. The fireball. The chaos. I remember many years later going out and seeing the huge dent in the water tower from the plane crash. That microburst was probably one of the reasons I became a meteorologist. (I wanted to be a Blue Angel, but I don’t have a penis.) I also remember the Yarnell Hill Fire. I was working at the NPS. I knew these men. I know why they died. There are many of us who know why they died. Long story, short, there was a cover up. Until the NPS/FS has a real conversation about this incident, they will be doomed to repeat it.
Please, help me understand what was covered up. The communication with the Supt and Asupt before they came off the ridge (the communication that led to the decision to cross unburned fuel in front of a head fire)? That there was no finger pointing or blame associated with those decisions? I was on a fire in AZ that day in June, not very far from the tragedy happened. I have been on fires around Yarnell. I understand, even after almost 9 years this is a very emotional topic. I did 6 years of IHC work. I understand how tense inter crew politics can be. For the rest of us current and former wildland firefighters, can you clarify the point you are making? What does the NPS have to do with this that the WHOLE DOI wouldn’t be involved with? What cover up? Are you referring to the lack of blame on human nature. This article is solely examining weather from that day.
14 Years Deep, I wish I could answer your questions. My heart is beating so fast (and yes, I’m still crying), because I really do want to answer your questions, but I can’t. There are legal repercussions. As for the article, the meteorology, I’m a meteorologist and the work that was done is pretty amazing. I ❤ NCAR!!! But, with that said, there is a difference between running models in future and past mode. When you run models in future mode it is so fast, but when you run it in past mode you can take your time, squeak it, make it look pretty. When I was doing prescribe burns I had about 47 seconds to run a model, but when I did SIP modeling I had months, even years to make it perfect. So, long story, short, a lot more work needs to be done to speed up the process and also deal with the meteorology that is created by the fire.
What are you sworn to secrecy? You say there’s a cover up and then not shed light on what you claim you know – doesn’t that make you part of the cover up?
Your tone was very definitive in what you wrote, if you’re not going to expound on what you claim you know than maybe rethink whether or not it’s worth bringing up in the first place.
Joe Schmo, you are right it’s hard to talk about it. I’m crying as I type this comment. I did get several calls after I posted the comment. I think a lot of people want to talk about it but are afraid of the repercussions. I know people who were forced to retire after the incident happened. And yes, I was very definitive in what I wrote, because of the legal ramifications. There’s so much I want to say and so much other people want to say, but we can’t. This article brings up some pretty dark stuff for a lot of us. So, I’m not sure why they are looking into this. As a meteorologist, I can’t blame this on a microburst and I can’t blame it on the modeling, because the modeling at the time and even today can’t deal with this level of detail on this scale. The models don’t really deal with fire meteorology. The other real problem is time vs detail in the model. And I have to say running a model in past mode vs future mode is totally different. In future mode you don’t know if your right and most like you’re not going to be because you don’t have a lot of time to do the model, but in past mode, looking backwards you can take your time and tweak the model. So, that can be a little dangerous. OK I’ve rambled. My point is a lot more work needs to be done on these models to make them faster and to deal with the micro-scale, the local weather that is created by the fire. You’re probably right, maybe I shouldn’t have posted what I did, but maybe it help others understand that they are not alone in the silence.
Sometimes the documented evidence even when owned is difficult to know what the best way is to present it to the Public at Large. Joe Schmo… Yet, as the eyewitness who was with the GMHS on those Weavers 6-30-13, I can guarantee there has been so many layers of omissions and one thing I will also state if we are alive then any weather stories after the facts being used as a way to sway another as oh that must have been it…Sonny and I were both on the Weavers watching that Weather coming from Prescott, Arizona very close to where the GMHS saw the same views.
Inter-crew freqs are absolutely essential for all IHC’s to function in a safe manner…..Period….However hey do at times cause friction, at times the things that are being discussed within the crew would also very much benefit neighboring resources.
Do not blame the WX for this tragedy, was it a contributing factor…sure it was, however this was 100% human error, sorry to be so blunt, I mean no disrespect at all, it was human decisions that led that crew off the hill and put them on a path of no return, it’s the truth, Old Guy nailed it, we have the 10 & 18 for a reason, if you have some time look up the report on the Inaja fire https://www.fs.fed.us/psw/publications/documents/psw_rn183/psw_rn183.pdf and from Bill G. https://wildfiretoday.com/2009/11/24/inaja-fire-november-25-1956/
I know that there are those that know exactly what happened, and I do hope that one day they will tell their story, we deserve to know the truth, we all know that some really bad decisions were made, but for some reason no one interceded and stopped the ensuing trainwreck. By that I am suggesting that there were those that should have spoke up, that is a real mystery to me, I know for a fact that my crew would have had very strong and very direct words for anyone leading them into a similar situation…..100%know it for a fact.
“Inter-crew freqs are absolutely essential for all IHC’s to function in a safe manner…..Period….However hey do at times cause friction, at times the things that are being discussed within the crew would also very much benefit neighboring resources.”
100% agree with this statement. I was merely pointing out that in the incident review summaries, these channels are never acknowledged to even exist, when they can cause “mission focus” or “tunnel vision” in communication.
Truth JK!
Old ECHS
One thing that never comes out during these investigations is the over-reliance on crew tac channels, or “secret squirrel” radio frequencies. I have no doubt in my mind that most of Granite Mountain’s decision making would have been a lot clearer after the fact had these tac channels not been in use. In fact, maybe someone would have stepped in and told them that point protection on an uninhabited structure wasn’t a good idea.
I know why they exist, I just don’t like ’em.
On the one hand it is very good that research is being conducted in trying to answer questions about what was the root cause that lead to massive fatalities. I hope we can learn valuable lessons over time to prevent anything like this from ever happening again.
On the other hand this type of weather is a well known occurance for us fighting fire season after season. Why it is that professors and universities are just now starting to figure this stuff out, shall remain a mystery to me.
I was there in Yarnell when this tragedy took place. Spending lots of money on trying to get high resolution radar data after the fact isn’t going to stop the loss of life – future or past.
Other paths have a higher likelihood of preventing death, such as the wind model being studied by the University of San Diego and implemented by FIRIS. Having each crew have a satellite transponder so that the IC has constant situational awareness would be another tool that could help prevent this tragedy from repeating.
Ten Standard Orders and 18 Watch Outs
Ten Standard Firefighting Orders
These basic ten guidelines have been successfully used by thousands of firefighters and leaders for more than forty years.
Appropriate use of these fundamental guidelines enable companies to safely work in hazardous locations because they have the ability to get an early warning of any serious hazard, and have the ability to escape to a safety zone before any fire behavior change could cause an entrapment.
These guidelines are also relevant for predicting and preventing many other fireline casualties
Keep informed on fire weather conditions and forecasts.
Know what your fire is doing at all times.
Base all actions on current and expected behavior of the fire.
Identify escape routes and safety zones and make them known.
Post a lookout where there is possible danger
Be alert. Keep calm. Think clearly. Act decisively.
Maintain prompt communication with your forces, your supervisor, and adjoining forces.
Give clear instructions and insure they are understood
Maintain control of your forces at all times.
Fight fire aggressively, having provided for safety first
18 Watch Out Situations
Fire not scouted and sized up
In country, not seen in daylight
Safety zones and escape routes not identified
Unfamiliar with weather and local factors influencing fire behavior
Uninformed regarding strategy, tactics, and hazards
Instructions and assignments are not clear
No communication with your company or supervisor
Constructing line without a safe anchor point
Building fireline downhill with fire below
Attempting a frontal assault on the fire
Unburned fuel between you and the fire
Cannot see the main fire and not in communication with someone who can
On a hillside where rolling material can ignite material below
Weather is getting hotter and drier
Wind increasing or changing direction
Getting frequent spot fires across the fireline
Terrain and fuels make escape to safety zone difficult
Taking a nap near the fireline
If you have carefully read the State and Federal Investigative Reports on the Yarnell Hill Fire; read two or three of the books that were written about this fire; have personally field-reviewed this fire landscape; and you have extensive firefighting and fire behavior experience “in the suck” to comprehend the complexities the Granite Mountain Hotshots were faced with, then, in spite of what the Reports stated, it is “fairly” clear why we lost these brave souls.
You might ask yourself would you have wanted your son or daughter leading these firefighters on the ridge, to then leave that ridge and “go downhill through unburned vegetation”(Point 1) “without communication with the Incident Commander nor with overhead airtankers” (Point 2) then not having a required Look Out in a safe enough position to report “any and all” weather and fire changes throughout the duration of your crew’s movement(Point 3)? So, the question remains: Why did the y leave the safety of the ridge they were on when an experienced Lead person knew better? Regretably, we will likely never know the answer
Granite Mountain Hotshots from Prescott, AZ*
those hot shots so emotionally attached to there town put there blinders on head down and walked them self into the no man ZONE EMOTIONAL decisions bad outcome my guess is the sup had a phone call or a radio call to get your ass down here now and save your TOWN NOW