Above: Vehicles at the scene of an accident on Interstate 40 Wednesday, October 19, 2016. Photo by Arizona Department of Public Safety.
(On October 20 we wrote a follow-up article about this incident which looks at the weather forecast and the smoke permit that preceded ignition of the prescribed fire.)
After numerous accidents occurred in thick smoke from a prescribed fire, authorities closed Interstate 40 west of Flagstaff, Arizona on Wednesday. The Kaibab National Forest conducted the burn Tuesday and knew that a wind shift would push the smoke toward the interstate, but they were surprised that the smoke settled near the ground early Wednesday morning rather than being moved out of the area. Electronic signs warned drivers about the potential hazard.
Below is an excerpt from Fox News:
Multiple collisions with minor injuries to motorists and passengers were blamed on smoky haze that settled over the highway for about five hours. Authorities closed I-40 for hours to prevent more accidents.
Police had not immediately determined whether the poor visibility was the cause of a fatal accident after a vehicle was sandwiched between two tractor-trailers before dawn, said Arizona Department of Public safety spokesman Bart Graves.
But the area at this time of year experiences temperature inversions allowing smoke to be trapped close to the ground and hover over the highway, said Cory Mottice, a National Weather Service meteorologist in Flagstaff.
“It almost always gets trapped after dark,” he said. “It’s just a question of where the wind blows it.”
Forest officials thought weather conditions would vent smoke near the freeway more than it did in low-lying areas, Smith said.
“I believed they used good judgment based on the conditions and the information that they had,” said Brady Smith, a U.S. Forest Service spokesperson.
There was a known risk–a history of smoke settling in the area of the highway this time of year. Based on quotations in the article, which I copied into my comment, my only assumption was that a fire manager who was aware of that risk should not have proceeded with the burn.
Forecasting specific weather conditions, especially for a relatively small area at a specific time frame is extremely difficult at best. Conditions can quickly deteriorate regardless of the forecast. For that reason, a known phenomenon should be given a higher level of consideration. Failure to remediate the “worst case scenario” is all that is necessary to create it.
I appreciate the further research you presented in your follow up article and I am satisfied the fire managers contacted weather personal. It also indicates they were aware of the possibility that smoke could cause a hazard on the highway.
I am concerned that decisions to proceed with a burn are still made when there are indicators otherwise, especially when loss of property and loss of life can be avoided. While they represent a relatively small percentage of prescribed burns, fires which escape or cause extreme ancillary hazards as this one did, often have in their history a risk that not given enough weight in the decision making process before ignition.
I haven’t talked to any of the folks involved, but I do know that the fire personnel when I was there (and numerous of them are still) were always very good about getting spot weather forecasts & monitoring general forecasts from the NWS for several days prior to any planned ignitions. There is a heightened level of awareness to impacts to the public by the local fire management because of the proximity to I-40 & the various small communities in the area.
Also, in Arizona the DEQ must approve all smoke management requests by 1400 the day prior to ignition. Without that approval, units do not burn.
In answer to Mr. Sundstrom’s question, both the Forest Service & National Park Service units in that area are required to communicate & work with those local & state offices before ignition.
On October 20 we wrote a follow-up article about this incident which looked at the weather forecast and the smoke permit that preceded ignition of the prescribed fire.
To paraphrase Alfred E. Newman of Mad Magazine: “What, me slow down?”
Does anyone know how far from the interstate the burn was?
It was close. More info here.
Is Thune right? There are some serious indications here the people who started this fire should have been required to consult local officials:
“But the area at this time of year experiences temperature inversions allowing smoke to be trapped close to the ground and hover over the highway,” said Cory Mottice, a National Weather Service meteorologist in Flagstaff.
“It almost always gets trapped after dark,” he said. “It’s just a question of where the wind blows it.”
I don’t think Thune’s bill requires contacting the National Weather Service, perhaps it should be amended. It would have been a minor inconvenience compared to what happened here!
You are making the assumption that the fire managers did not consult with the National Weather Service. It would be very, very unusual if they didn’t.