Hurricane Kay is forecast to track north along the Baja California Peninsula through Friday. It will then turn westward off the coast just short of the US-Mexico border, but not before making the closest pass to Southern California for a hurricane since 1997’s Hurricane Nora. Kay is expected to remain at hurricane strength until it is about 250 miles from San Diego, something only four other storms have done since 1950, according to the National Weather Service, before weakening as it approaches. But the storm doesn’t have to be strong “to be a significant concern for Southern California,” said Brandt Maxwell, a San Diego NWS meteorologist. Forecasters warn that the system could intensify the region’s suffering from extreme heat, rather than alleviate it. Winds could gust more than 60 miles per hour as the system interacts with the mountainous terrain of Southern California. And those winds will come from the east, meaning they will have a warming effect on coastal cities. As the air travels down the mountains, it is compressed and its temperature increases. It will be similar to the Santa Ana wind phenomenon, which usually occurs in the fall and winter. “We don’t call them Santa Ana winds, but they will have their characteristics as they go through the canyons and the sloping terrain,” Maxwell told CNN. Warm, dry easterly winds will increase fire danger in the area. Temperatures could reach 100 degrees in coastal areas of San Diego and Orange counties on Friday. “This happened in 1984 as a Category 1 Hurricane Marie southwest of San Diego County forced temperatures to reach 100 degrees in San Diego,” Maxwell said. Overnight lows could remain in the 80s Thursday night and into Friday morning, making sleep uncomfortable, especially for those without air conditioning. Then, the unrelenting heat will “end abruptly and unusually” late Friday, the Los Angeles NWS said, as the tropical system’s cloud cover and rainfall move into the region, sharply lowering temperatures but creating new dangers. Although the Southwest has been mired in a multi-year mega-drought, Kay’s rainfall could pose a significant flood threat. “Confidence is rapidly increasing for a significant rainfall event across Southern California, Arizona and eventually central California and Nevada by Saturday,” forecasters at the Weather Prediction Center wrote on Wednesday. East-facing slopes near the Santa Rosa and San Jacinto mountain ranges could see the heaviest rainfall, with up to 4 inches possible by Friday. The WPC has issued a rare level 3 out of 4 outlook for excessive rainfall in this area for Friday. Although rainfall is desperately needed across parched Southern California, this much rain in a short period of time can cause creeks and rivers to rise rapidly. “It’s never good to get too much rain at once, a feature very common in slow-moving tropical storms,” the WPC said. “Thus, the potential for flash flooding increases summarily and rapidly.”
