Hurricane Hilary Churns Toward Baja California

Californians don’t typically spend a lot of time worried about hurricanes and tropical storms.

It’s been nearly 84 years since a tropical cyclone made landfall in Southern California. That was in September 1939, when an unnamed storm hit Long Beach.

“To those who must face it, a 65-mile wind blowing across open water is devastating,” The New York Times observed at the time, adding, “No one looks for heavy weather on that pleasant stretch of coast.”

But no one seems to have told Hurricane Hilary that. As of 2 a.m. Pacific time, the storm, which formed off the coast of Manzanillo, Mexico, on Wednesday, was churning west-northwest toward Baja California with sustained winds of 145 miles an hour — a major Category 4 storm — according to the National Hurricane Center.

The storm’s angle to the coast makes it difficult to pinpoint where, exactly, Hilary will make landfall, but forecasters are confident that the storm will continue on its current trajectory, turning north today and moving up the west coast of Baja California. Forecasters say Hilary will probably weaken over the weekend as it moves over colder waters, and be downgraded to a tropical storm by the time it reaches the United States.

Regardless of where the storm makes landfall, it is likely to bring heavy rain — and a chance of flash flooding — to Southern California, possibly as soon as Saturday morning and continuing through Monday. The National Weather Service has issued a flood watch for Los Angeles and Ventura Counties, including Catalina Island, from Sunday afternoon until Monday evening.

Stefanie Sullivan, a forecaster with the Weather Service in San Diego, said a worst-case scenario for Southern California would be if the track made landfall in California. That would mean stronger winds than if the storm made landfall farther south, and would increase the threat of destructive surf and rip-current conditions for the region.

The better scenario for Californians — landfall in Mexico — could be a worse one for Arizonans. If the storm tracks farther east into the Baja California peninsula over the next couple of days, the moisture and heavy rainfall would be shifted east.

A difference of just 100 miles or so in the track of the storm could mean a large change for the expected weather, forecasters with the Los Angeles weather office said.

Ms. Sullivan said it was “exceedingly rare” for a tropical storm to come off the ocean and make landfall in California. But storms have caused flooding and brought dangerous winds, even if they’ve only come close or have weakened before arrival. Last year, Kay, a post-tropical cyclone, brought high winds and rainfall when it moved up the coast of Baja California.

Some past storms have moved across the state after coming ashore in Mexico. In 1997, Hurricane Nora made landfall in Baja California before moving inland and reaching Arizona as a tropical storm.

What about farther back in history? A study published in 2004 in The Bulletin of the American Meteorological Society found that one had struck San Diego in 1858. “A terrific gale sprung up from the S.S.E. and continued with perfect fury until about 5 p.m.,” The San Diego Herald reported in October 1858.

This year’s hurricane season in the Eastern Pacific, which runs from May 15 to Nov. 30, has been complicated by the development of El Niño, a large-scale weather pattern that appears intermittently and can have wide-ranging effects on weather around the world.

In the Pacific, an El Niño pattern tends to reduce wind shear, a term that refers to winds blowing in different directions and speeds at one altitude than at another. Because wind shear tends to prevent cyclones from forming and intensifying, less of it means a greater chance for a big blow.

Where we’re traveling

Today’s tip comes from Jim Frazier, a retired wildland hydrologist in the Stanislaus National Forest, about two hours southeast of Sacramento. Jim recommends what he calls the Sonora Loop:

“The historic gold mining town of Sonora, renowned as the Southern Queen of the Mother Lode, is the starting line for a stunning adventure up and over the Sonora and Tioga Passes, the two highest road crossings in the Sierra Nevada mountains. They’re only a neighborly 30 miles apart and a tall tree or two from 10,000 feet high.

The loop begins by heading east from Sonora up State Highway 108 through the beautiful Stanislaus National Forest and crests at 9,628 feet at Sonora Pass. It continues eastward down to U.S. Highway 395 on the east side of the mountain range. The loop turns south on 395 to the small town of Lee Vining, near Mono Lake, the halfway point on the trip. From there it heads westerly up State Highway 120 until reaching Tioga Pass at 9,945 feet, the eastern entrance to Yosemite National Park. The loop then begins its gradual descent down Highway 120 through Yosemite and back to Sonora.

The loop can be done on one long summer day, though two or more days are highly encouraged to enjoy the many breathtaking stops along the way. The entire route is on well-paved, two-lane roads with scenery galore.

The loop is usually open from mid-June to late October, mountain weather permitting. Spectacularly green forested scenery spreads amid bright granite mountains, some with ancient dark lava flows atop them. Sparkling lakes, rivers and streams abound. Spring and summer offer eye-popping wildflowers and brilliant skies. Autumn brings out the spectacle of yellow quaking aspen and cottonwood trees, willows and other flora changing into dazzling colors.”

Tell us about your favorite places to visit in California. Email your suggestions to CAtoday@nytimes.com. We’ll be sharing more in upcoming editions of the newsletter.

Tell us

A number of Los Angeles landmarks are turning 100 this year, including the Hollywood sign, the Memorial Coliseum and the Biltmore Hotel downtown.

Do you have favorite memories of these L.A. institutions? Share them in a few sentences with CAtoday@nytimes.com, and please include your name and the city where you live.

And before you go, some good news

An inn in Big Sur has a strange but charming claim to fame: its so-called river chairs.

At some point, someone took an Adirondack chair from the Big Sur River Inn and set it directly into the Big Sur River so that the current washed over its legs. Lounging in those chairs — there are now many of them — has become a tradition at the hotel, SFGate reports.

“We really don’t know how the thing got started, but it became a thing,” the inn’s general manager, Rick Aldinger, told the news outlet. “It’s become a real institution.”