YOSEMITE NATIONAL PARK, California (AP) — Fire crews took advantage of a relatively cool and humid day to make major progress Monday toward containing a massive wildfire searing the edge of Yosemite National Park.

The fire was 70 percent contained at nightfall, up from 45 percent some 24 hours earlier, according to the California Department of Forestry and Fire Protection. The blaze now covers 368 square miles (953 square kilometers), about 20 square miles (52 square kilometers) more than Sunday night.

Fire weather was still classified as extreme with temperatures above 90 degrees Fahrenheit (32 degrees Celsius) and winds in some spots gusting at 20 mph (32 kph), but Monday was cooler than many recent days, with more moisture and cloud cover.

Full containment is not expected until Sept. 20.

Crews will continue building fire lines and burning away the fire's potential fuel sources on Monday.

"We do have a nice window here of more cooperative weather," state fire spokesman Daniel Berlant said.

Gusty winds and dryer conditions are expected midweek, however, again raising the fire danger, Berlant said.

The blaze started Aug. 17 in the Stanislaus National Forest, and two-thirds of the land burned since then is located there as well. The cause is being investigated.

The fire — the fourth largest in California history — has claimed 111 structures, 11 of them homes. About 4,500 structures are threatened.