SOUTH LAKE TAHOE, Calif.—When the Caldor Fire roared toward a granite ridge above South Lake Tahoe last month, some computer models that firefighters were using showed the blaze stopping in its tracks. A conflicting calculation showed something unprecedented: the inferno jumping the ridge and racing toward the resort.
Stephen Volmer, a state fire-behavior analyst crunching the scenarios in a trailer 40 miles away, leaned toward the first outcome because the ridge had always shielded the lake from wildfires. “If the winds were calm,” he said, “everything looked fine.”
