Causes of the 1988 Yellowstone Fire

In 1965, a typical Yellowstone black pine forest.

Yellowstone National Park began formal fire record archiving in 1931, when the Hutt Lake Fire burned 73 square kilometers (18,000 acres). Although the fire was small, it was the largest fire in Yellowstone National Park from its founding until 1988. Research shows that fires occur on the Yellowstone Plateau 2 to 3 times every 1,000 years. The last large-scale fire that occurred in Yellowstone dates back to the early 18th century, long before white colonization.

Yellowstone forests are dominated by lodgepole pine, which is usually eventually replaced by other tree species when the forest matures after 80 to 100 years. In Yellowstone, where the higher latitude and poor soil result in a short growing season, lodgepole pine can survive for 300 years before other tree species such as Engelmann spruce and subalpine fir establish their dominance. Lodgepole pines are found in high densities throughout the highlands of the Yellowstone Plain. Although lodgepole pine can be found in other mature forests, it is not found in such high densities in other forests in the Rockies. In the 1980s, many lodgepole pine forests in Yellowstone Park had been growing for 200 to 250 years and were about to reach the end of their life cycle. The Norris Fire Fighting Site on August 20, 1988 was called "Black Saturday" because a large amount of land was burned and dense smoke swirled from morning to night in some places.

Between July and August, about 250 different fires burn in Yellowstone and surrounding national forests a month. The burned area in 7 of them accounted for 95% of the total burned area. By the end of July, the National Park Service and other agencies had mobilized all their manpower, but the fire continued to spread. Small fires spread together, exacerbated by dry thunderstorms that brought high winds and lightning but no rain. The worst day, August 20, became known as "Black Saturday" when more than 610 square kilometers (150,000 acres) of land were destroyed. Ashes from the fire cyclone enveloped the entire park and even spread as far as 96 kilometers northeast to Billings, Montana. The wind blew the flames over roads and fire escapes, and embers started a new fire about a mile in front of the original fire. Surface fires spread up to the forest crown, becoming crown fires, with flames reaching heights of 60 meters (200 feet). On that day, more acreage of Yellowstone was burned than in all fires since the park's founding combined. Throughout the summer, the fire advanced 8-16 kilometers (5-10 miles) per day, and reached a peak of more than 3.2 kilometers (2 miles) an hour.

The Snake River Fire is one of the larger group of fires. These fires occurred in the southern part of the park, where the Yellowstone and Snake rivers originate. The Shoshone Fire, the largest of the group, was started by lightning on June 23. Natural fire management policies were still in effect at the time, so initially there was no organized effort to put out the fires. The fire smoldered on a small scale for several weeks, rapidly spreading to the northeast on July 20. The surface fire in Grant Village traveled up into the forest crown and became a crown fire.

On July 1, the Red Fire started burning near Lake Levis. Like the Shoshone Fire, it did not spread widely in the first few weeks. On July 19, the fire began to spread northeastward, and in August it merged with the Shoshone Fire. As the fire advanced into Grant Village, evacuation orders were issued so firefighters could concentrate on protecting the buildings. Due to its location in the middle of a lodgepole pine forest, Grant Village was the first major tourist area to be affected by the fire. Many small buildings and some camping sites were destroyed. After the Red Fire and the Shoshone Fire came together, they were collectively known as the Shoshone Fire because the latter was much larger. The Mink Fire, which started burning in the Bridger-Deaton National Forest on July 11 and was also caused by lightning, spread north along the Yellowstone River Valley after firefighters forced it off private land. After July 23, the Mink Fire finally burned into Yellowstone Park, but due to its remote location in the park, its hazard is generally considered not serious. The third fire, the Hawk Fire, started on August 20 when a tree fell on power lines. The fire burned primarily along the Rockefeller Memorial Highway, crossing Yellowstone's southern border on August 30. By the time the Snake River Fire was extinguished by wet weather in the fall, it had burned more than 570 square kilometers (140,000 acres). The most alarming thing during this period was when the fire swept through the Levis River Gorge on August 23, with a spreading speed of 128 kilometers (80 miles) per hour under the influence of winds of 96 kilometers (60 miles) per hour. From July to October 1988, the Great Fire Fire processes in the Yellowstone region.

On July 9, the Mister Fire began burning on the Absaroka Ridge in the eastern part of the park. Two days later, the Clover Fire ignited in the same area. On July 20, two fires spread together and were collectively known as the Clover Mister Fire. Due to the rugged terrain, the fire was difficult to extinguish. On August 20, the fire spread to the south of the town of Cook and continued to threaten the town for several weeks. In total, the Cloverfield Fire burned more than 570 square kilometers (140,000 acres). The Storm Creek Fire started burning in the Absaroka-Beartooth Wildlife Area on July 14 and for two months appeared to be causing minimal damage to Yellowstone.

However, on August 20, the fire quickly spread southward, this time endangering the north of Cooktown. Firefighters tried to control the wildfire, using special backfire methods. Inflammable materials are set up in front of the burning direction of the fire, and another fire is ignited, allowing it to burn back to achieve the purpose of extinguishing the fire with fire. This approach turned out to be self-defeating and almost caused a disaster. Due to a sudden change in wind direction, the flames spread to within 100 yards of the town, necessitating the evacuation of people on September 6. The main fire in the northern part of the park is the Hale Rolling Fire, which has been burning in Gallatin National Park since August 15 due to the remains of an unnoticed campfire. The fire initially spread north, then turned south a few days later, threatening the area near Tower Junction. The Van Fire began burning in the northwest on July 5 and was initially thought to threaten the town of Gardner, Montana, just outside the park's northern exit. This was the most successful fire extinguishing campaign in 1988. Although the fire burned for several months, by mid-August it was no longer considered a threat to life and property.

The North Fork Fire was the largest fire, both in terms of the number of buildings burned and the area burned. The fire started on July 22 when a logger dropped a cigarette in the Cariboo-Taye National Forest on the park's western boundary. The North Fork Fire was the only fire to be fought as soon as it was discovered, as it occurred after the original fire policy was suspended on July 15. The fire spread northeast and threatened Madison Junction and nearby campgrounds during the first weekend of August. On August 20, the fire quickly spread to the Norris Geyser Basin. Firefighters used water and firefighting foam to prevent the building from being hit by the blaze. The fire continued west along the Yellowstone Plateau and reached the visitor center of the Grand Canyon of Yellowstone Park on August 25. The Bureau of Land Management and the U.S. Army deployed a large number of manpower to protect local buildings. After a few days, the east side of the flames was extinguished, and downwinds from the Yellowstone Canyon caused the fire on the west side to threaten the town of West Yellowstone. Ordinary people helped government crews soak hundreds of acres of forestland to protect towns and power stations. The fire burned much of the forest in the Madison River Valley. On September 7, 1988, the North Fork Fire reached the Old Faithful structure.

Between September 5 and 7, the southern flames of the North Fork Fire reached the large visitor area near the Old Faithful Basin. All non-staff personnel were ordered to evacuate, but political issues affected the command of the U.S. Park Service and the scenic area was not completely closed to tourists. Some tourists still visited Old Faithful until shortly before the fire cyclone spread there in the afternoon. Firefighting aircraft dumped fire retardant to extinguish the fire, but failed. Firefighters concentrated their efforts on protecting buildings, especially those of historic importance such as the Old Faithful Hotel. They use fire trucks and mobile pump systems to keep building roofs and other surfaces moist. 1,200 firefighters, including 120 military personnel, dug fire breaks and cleared flammable materials around the building. Winds reached 128 kilometers (80 miles) per hour, driving the fire approaching from the west. Eventually the fire spread into nearby forest and left the main buildings, but 19 smaller buildings and an old dormitory were destroyed. The fire was so intense that those vehicles that did not evacuate had melted wheels, shattered windshields and scorched paint. Although most of Old Faithful's structures were preserved, on September 8, the Park Service decided for the first time that the entire park would be closed to non-emergency personnel. On the night and morning of September 9 and 10, the North Fork Fire crossed a fire break on the northeast side and approached Mammoth Hot Springs, where a large group of historic buildings and the Park Service headquarters are located. The timely arrival of rain and snow stopped the fire before it threatened the building. The North Fork Fire was eventually extinguished and destroyed more than 1,600 square kilometers (400,000 acres), accounting for 60% of the park's total burned area. On September 11, cold air brought rain and snow, and fires throughout the Greater Yellowstone Ecosystem gradually extinguished. Although the fire was still burning in mid-November, there was no longer a threat to life or property. Many firefighters began to retreat, and other manpower arrived in Yellowstone to restore the damaged area. Hundreds of miles of fire lines, helicopter landing areas and fire camps need to be restored to their original condition. Thousands of dangerous dead trees need to be cut down to protect roads and buildings. Finally, on November 18, all the fires in Yellowstone were extinguished.