Bill Gray, shown in 2008, set up many of the foundations of hurricane prediction. (Peter Cosgrove/AP)

Bill Gray, a leading and respected practitioner of hurricane science who changed the way the world looks at those massive storms and who late in life drew attention for his strident challenges to the science behind ­human-caused climate change, died April 16. He was 86.

Colorado State University in Fort Collins, where he was a professor emeritus of atmospheric science, announced his death. No cause was released.

Dr. Gray, a full-time Colorado State professor from 1961 to 2005, built his reputation as the creator in the early 1980s of modern seasonal forecasts for Atlantic storms. These forecasts have been avidly covered by media outlets to warn residents and have also proved useful to insurance companies, storm-window manufacturers and other groups with major stakes in hurricane prognostication.

“Anyone who could say anything about the coming season, that was big stuff,” Dr. Gray told the Los Angeles Times. Shunning computer and mathematical models that have become the standard, he put his faith in observational science: historical storm data, old maps featuring storm patterns and statistics on wind speed, water temperatures and other meteorological factors.

“If you combine all these things,” he told the Times, “there’s some memory that the atmosphere has of what’s going to come in the future.”

The outlooks are now ubiquitous, with commercial forecasters and the National Oceanic and Atmospheric Administration issuing seasonal predictions for Atlantic tropical storm and hurricane development. Colorado State still does its own, now under Phil Klotzbach, a Gray protege. Many of the techniques and methods Dr. Gray developed and refined are still in use.

“Bill is one of the heroes in this business,” Roger Pulwarty, a research scientist with the NOAA in Boulder, Colo., told the Denver Post in 2004. “His work has been fundamental to our understanding of why the number of hurricanes in the Atlantic varies from year to year. It’s extremely important for countries in the Caribbean, because it gives them a sense of what to expect.”

Dr. Gray also wrote a 1968 paper about the genesis of tropical cyclones, the class of storms that includes hurricanes and typhoons. He tied together many of the factors that the storms needed to form and showed that wind shear can damage their structure.

“It’s still a landmark contribution,” said Chris Landsea, science and operations officer at the Technology and Science Branch at the National Hurricane Center and a former student of Dr. Gray’s. “I think before that paper, parts of it were understood, but it wasn’t put together in a coherent whole. He put it all together and demonstrated it globally. A lot of forecasters around the world changed their methodology.”

William Mason Gray was born in Detroit on Oct. 9, 1929, and grew up in Washington. He graduated from Wilson High School, where he was a standout baseball player, and then from George Washington University in 1952.

During service in the Air Force, he turned to a career in climatology. He vividly recalled flying through Hurricane Helene off the east coast of Florida in 1958 and seeing the dramatic waves close up. “Take a young graduate student, fly him into waves, and he gets excited,” he told the Los Angeles Times.

He later received a master’s degree in meteorology and a doctorate in geophysical sciences from the University of Chicago, studying under noted meteorologist Herbert Riehl.

In 1954, he married Nancy Price, who served as mayor of Fort Collins in the early 1980s. She died in 2001. A daughter also died before him. Survivors include three children and two grandsons.

Starting in the 1990s, Dr. Gray developed a reputation as a combative figure on global warming.

“I am of the opinion that this is one of the greatest hoaxes ever perpetrated on the American people,” he told The Washington Post in 2006, regarding the significant impact humans are believed to have had on global warming through the production of greenhouse gases. He hewed to a belief in “natural” cycles of planetary heating and cooling and did not put stock in theories about “man’s influence.”

He likened apocalyptic fears of a hotter planet to a “hysteria,” saying that he recalled panics in the 1970s about global cooling that some said would culminate in an ice age. “I don’t think this warming period of the last 30 years can keep on going,” he told The Post. “It may warm another three, five, eight years, and then it will start to cool.”

His professional clout gave him access to policymakers and high-platform forums to espouse his views, but those same views put him in a distinct minority of scientists who specialize in climate change.

CORRECTION: An earlier version of this story incorrectly reported that Dr. Gray died Aug 16. The story has been updated.