Hurricane or tropical storm in California? It’s not impossible – Daily News

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Hurricane Kay, which made landfall over central Baja California on Thursday, Sept. 8, is expected to bring heavy rainfall and strong winds to Southern California starting Friday, but shouldn’t pass directly over land on the U.S. side of the border.

A direct hit in California would be exceedingly rare — but not without precedent.

In recorded history, only one hurricane has made landfall in California. It hit San Diego in October 1858 and is estimated to have been at Category 1 strength. In September 1939, a storm that had just weakened from a hurricane to a tropical storm came ashore near Long Beach.

Two other systems made first landfall in Mexico but were still at tropical storm force when they arrived in California: Kathleen in September 1976, which crossed into the U.S. south of the Salton Sea, and Nora in September 1997, which passed over the point where Mexico, California and Arizona all meet.

The effects of tropical cyclones (the term used for any rotating storm system over tropical or subtropical waters — they’re categorized as tropical depressions if the winds are 38 mph or less, tropical storms with winds of 39-73 mph and hurricanes with winds of 74 mph or more) can extend across hundreds of miles, so it’s not unusual for systems to send clouds and rain into Southern California, but Kay will be the closest that one has come since 1997.

“Tropical cyclones come up there every now and then and have direct impacts every generation or two,” said Eric Blake, a senior hurricane specialist with the National Hurricane Center.

The forecast as of Thursday afternoon predicts Kay will head northwest for the next several days, weakening to a tropical storm by Friday morning and a depression by Sunday. There’s a chance it could get north of the Mexico/U.S. border, but it should be well out over the ocean by then.

1858: ‘A perfect hurricane’

In a 2004 paper for the American Meteorological Society, two meteorologists used historical newspaper accounts and weather records from the U.S. Army and Coast Guard to determine that the 1858 storm that hit San Diego was probably a Category 1 hurricane.

According to an account in the Daily Alta California, on the morning of Oct. 2, “the wind gradually increased, and the whole heavens seemed closing in with bank upon bank of dark, heavy, ominous-looking clouds, fleeting pretty close down to the ground, before the increasing gale.

“Several very heavy gusts of wind came driving madly along, completely filling the whole atmosphere with thick and impenetrable clouds of dust and sand, so much so, that one who was in the street could no more see around him than if he was surrounded by an Egyptian darkness; this continued for a considerable length of time, the violence of the wind still increasing, until about one o’clock, when it came along in a perfect hurricane, tearing down houses and everything that was in its way.”

The Los Angeles Star reported heavy rain and some damage to the wharf at San Pedro. Other reports indicated that there was heavy rain as far north as Fresno and Visalia, according to the American Meteorological Society paper.

1939: ‘The Lash of St. Francis’

An unprecedented four tropical cyclones affected Southern California during September 1939, with the last being the most devastating.

According to the National Weather Service, a tropical storm referred to as “El Cordonazo” or “The Lash of St. Francis” made a direct hit at San Pedro on Sept. 25 and brought the greatest September rainfall ever to the region. Los Angeles got 5.42 inches in 24 hours, and Mount Wilson got 11.6 inches. The storms put the eastern Coachella Valley under 2 inches of water.

Flooding killed 45 people across Southern California, while 48 more died at sea, the weather service reported.

The storm caused $2 million in damage along the coast — but that American Meteorological Society paper estimated that if the 1939 storm had hit in 2004, with inflation and the region’s increase in population and wealth, it would have caused roughly $200 million in damage.

1976: Catastrophic Kathleen

Tropical Storm Kathleen — which had briefly been a hurricane over the ocean — hit Baja California on Sept. 9 and crossed into the U.S. on Sept. 10, wreaking havoc in California and Arizona with winds still well above the 39-mph threshold of a tropical storm and a deluge of rain.

In the community of Ocotillo in Imperial County, “About half the town’s 400 residents were evacuated … when a six-foot-high wall of water rumbled out of a ravine and poured through the center of town,” The Associated Press reported at the time. The damage was catastrophic, with flooding destroying 70-80% of the town, according to a NASA description of the storm. Six residents were killed, half of the storm’s total fatalities in the U.S. Portions of Interstate 8 and a railroad were destroyed.

Elsewhere in Southern California, the southern slopes of Mount San Gorgonio got almost 15 inches of rain and Mount San Jacinto got more than 10 inches, according to the National Weather Service.

1997: Linda misses, Nora hits

The first threat to Southern California in September 1997 was Hurricane Linda, the strongest storm recorded to that point in the eastern Pacific. It reached Category 5 status, with peak winds on Sept. 12 estimated at 185 mph.

“For a couple of nerve-wracking days, National Hurricane Center forecasters warned the storm could barrel into Southern California, most likely as a tropical storm,” says a NASA summary of the storm. “Fortunately, the storm turned westward away from land.”

Even so, the associated rain caused disastrous flooding and mudslides in the San Bernardino Mountains, damaging or destroying nearly 80 homes.

Then on Sept. 25, Hurricane Nora hit Baja California. Moving almost due north, it skirted water again in the far northern Gulf of Mexico and came into the U.S. near Yuma at the California/Arizona border, with winds still at tropical storm strength.

Nora brought 5.5 inches of rain to Mount San Jacinto and 3 inches in Twentynine Palms. The storm was blamed for several traffic deaths and caused extensive damage to agriculture.

A map shows the tracks of named storms between late August and November 1997, including Linda (labeled #12) and Nora (labeled #14). (Courtesy of National Weather Service
A map shows the tracks of named storms between late August and November 1997, including Linda (labeled #12) and Nora (labeled #14). (Courtesy of National Weather Service

Why aren’t there more?

Direct hits to California are rare for several reasons.

First, tropical systems that form in the Northern Hemisphere generally travel west or northwest because of the Earth’s rotation. Eastern Pacific hurricanes are born in the waters off the coast of southern Mexico and Central America, so to reach California, they’d have to veer north to an unusual extent.

Additionally, storms need very warm water to give them the energy to turn into hurricanes, and the Pacific off California just doesn’t cut it.

“Our waters here are about 10 degrees colder than waters in Mexico,” said Ivory Small, a meteorologist with the National Weather Service office in San Diego, which also covers Orange County and the Inland Empire.

So what’s allowing Kay to get so close to California?

This is the time of year when our ocean water tends to be warmest, so it may be no coincidence that September and early October are when tropical storms have gotten closest. Small said another key factor is that right now we’re missing the winds that would normally push storms west toward Hawaii — which he said is a side effect of the recent heat wave.

Blake, from the National Hurricane Center, said scientists will study Kay to determine exactly what happened and whether climate change had a real impact on bringing a storm so far north.

But for now, he said, the focus is on the immediate danger the storm could bring.

“Pay attention to your local weather service office about high wind warnings as well as flooding,” he urged.

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