Undated (AP) _ California firefighters battled more than 170 fires, while gusts in Yellowstone threatened to fan a 90,000-acre blaze toward 600 cabins and the park superintendent said there was no end in sight to this summer's wildfires.

Montana ranchers prepared for possible evacuation today, and crews fought woodland blazes in Idaho, Oregon, Washington, Nevada and Utah.

In California, nearly 9,500 lightning strikes Tuesday sparked scores of blazes a year after a similar barrage spawned devastating fires. Firefighters said more than 4,600 acres had burned, but they held most of the blazes to an acre or less in the drought-parched wildlands.

Crews were hampered by 100-plus-degree temperatures, winds and lightning in some areas. The unfavorable conditions were expected to continue today.

Altogether on state land, 73 lightning-sparked fires burned 2,700 acres, said state Department of Forestry spokeswoman Karen Terrill.

U.S. Forest Service spokesman Matt Mathes said 43 lightning-caused fires in Southern California national forests burned just 30 acres, while 60 blazes in Northern California national forests blackened 1,900 acres.

''We are flying over the areas to determine if there are any (other) hot spots,'' Terrill said.

Near San Francisco, fire swept through dry brush and trees Tuesday in Orinda, destroying five houses and badly damaging two others.

Police believe an electronically ignited toy rocket may have sparked the blaze, which was controlled in about two hours without reports of injuries.

''This has been the worst time of my life,'' said Beverly Hopp, whose 33- year-old home was destroyed. ''What do you do after all these years?''

The only thing she and her husband, Al, could save was a desk containing money and insurance papers.

In Wyoming, flames from the 90,000-acre North Fork fire at Yellowstone National Park moved to within a quarter-mile Tuesday of the Canyon hotel and campground complex. A military helicopter dropped foam on the visitors center and other buildings in the complex, which includes hundreds of wooden cabins.

Park officials closed the area last week when flames moved to within a half mile.

Firefighters hoped for an early winter to quell blazes burning about a fifth of the 2.2 million-acre park, but Yellowstone's superintendent offered little encouragement.

''When will this end? Frankly, ladies and gentlemen, that's anybody's guess,'' Robert Barbee told about 100 people Tuesday night at a meeting in nearby Gardiner, Mont.

Gusty winds forecast for this afternoon threatened to again close some park roads that were put off limits Tuesday afternoon but later reopened. The wind ended several days of calm weather.

Yellowstone spokeswoman Linda Young said activity on the 34,000-acre Wolf Lake fire forced closure of one road, and a flareup in North Fork blaze closed Yellowstone's west entrance for several hours. The entrance was later reopened, but Young said it could be closed again today depending on the fire's activity.

To the north in Montana, winds played havoc with efforts to control the 190,000-acre Clover-Mist fire, burning in Yellowstone and in neighboring Shoshone National Forest.

Officials closed U.S. 212 near Cooke City for a time Tuesday as soldiers chased spot fires.

Ranchers were planning for possible evacuation today along western Montana's Rocky Mountain Front where a previously ''let-it-burn'' wilderness fire jumped onto national forest and private land Tuesday. Hundreds of firefighters rushed to keep it from spreading further.

The 39,000-acre blaze in the Scapegoat Wilderness roared into Lewis and Clark National Forest, burning 7,000 additional acres.

Livestock and horses were removed from cabins threatened by the 9-week-old blaze, which was sparked by lightning, and some ranchers left as a precaution. Authorities did not know how many people lived in the sparsely populated area.

In Idaho, crews near the Wyoming line worked to protect ranches in the Caribou National Forest after a 6,000-acre fire burned to within a mile of the properties Tuesday. One family was evacuated because they lack a telephone and couldn't be notified in case the blaze blew up. Seventeen major fires are burning 70,000 acres in Idaho.

The number of firefighters more than doubled Tuesday to 679 at Oregon's biggest forest fire, which has burned 36,000 acres in the Wallowa-Whitman National Forest and the Hell's Canyon National Recreation Area.

Favorable weather in eastern Washington helped thousands of firefighters gain a handle on fires burning on more than 23,000 acres. Winds were light Tuesday as crews cut trails around nearly 70 percent of major fires on the Colville Indian Reservation and the Colville National Forest, officials said.