A rare September storm is heading straight for California, courtesy of a ... typhoon. [View all]

There are three of these typhoons spinning off the coast of Japan. Even though that’s over 5,000 miles from us, we’re likely going to feel some residual impacts.

Typhoon Merbok is being pushed by neighboring typhoons north, toward the jet stream. Weather models show that Merbok will eventually lose its typhoon status and its remnants will get absorbed into the jet stream, churning its moisture into Alaska by Thursday and Friday.

Starting Saturday, the new storm will slide south into the West Coast, where the European, American and Canadian weather models expect the center of the system to be just off the coast of the Bay Area. There is a wide range of possible impacts from this storm depending on whether the center stays over water, or inches closer to land.

Both the European and American weather models have been going back and forth on the timing of the first rain showers, but for now it is looking like the earliest showers will arrive in Northern California around Saturday night. Most of these initial showers will hover over the southern Cascades and the Mendocino Coast before eventually curling into the San Francisco Peninsula, the Sonoma Coast and the Central Coast by Sunday morning.

PAYWALL: https://www.sfchronicle.com/weather/article/Typhoon-will-bring-a-rare-September-storm-to-17441978.php


Predictions from the link:

• Rainfall totals by the end of Sunday to range from a tenth of an inch to as much as a third of an inch in the North Bay highlands, the Santa Cruz Mountains, on the Peninsula and in the Berkeley hills, while some isolated northwest-facing areas on the coastline may see up to a fifth of an inch of rain.

• The Central Coast: Monterey Bay forecast to see between a quarter of an inch to three-quarters of an inch of rain. The Big Sur coast could see much higher totals, over an inch if enough moisture curls into the Santa Lucia mountains on Sunday.

• Showers are then likely to develop over the Sierra Nevada by Saturday afternoon, with some models even bringing rain showers over the Mosquito wildfire perimeter.

• Some models expect as much as four-tenths of an inch of rain, while others lean toward less than a tenth of an inch.

• Sierra residents above 3,000-4,000 feet may wake up to flurries and even a couple of inches of snow on the ground.

• The area where the Mosquito Fire is burning could also get a dusting.