The blaze was first reported shortly after 8 a.m. Wednesday and quickly exploded in size amid powerful Santa Ana winds, extremely dry air and unseasonably high temperatures. Wind gusts above 80 mph also grounded water-dropping helicopters and fixed-wing tankers, complicating the task of fighting the fire as it zigzagged along the parched brush- and chaparral-covered hillsides.
While weather forecasters expected conditions to be even hotter and drier Thursday, fire crews expected to make more progress in Day 2 of the wildfire.
"We anticipate a good day, hopefully nothing will happen," said Rancho Cucamonga Fire Chief Mike Bell.
Officials are relying on bulldozers and hand crews to shore up the blaze's western front before it reaches the ridges between Day and Deer canyons, officials said.
No injuries or major damage had been reported as a result of the blaze so far. Fire officials on Thursday said one house sustained minor damage, but did not elaborate. More than 1,600 homes on Wednesday were under mandatory evacuation orders, but those were downgraded to voluntary by the afternoon.
“The bad news is, we're going to have some tough, hot, dry, windy conditions to fight that fire, and in case any other fire gets started, it's going to spread quickly,” said Miguel Miller, a forecaster with the
Meanwhile, sustained winds blowing southwest will continue to push plumes of smoke and ash into Rancho Cucamonga and beyond.
"It's going to be sunny and smoky," Miller said.
The winds, however, should begin to subside after noon, and drop to a "light breeze" by the evening, he said.
The National Weather Service extended its red flag fire warnings through Thursday morning and predicted that temperatures could near 100 degrees in downtown Los Angeles and other areas as high pressure continues to grip the region.