Tropical Storm Rachel was centered 720 miles south-southwest of San Diego at 8 p.m. PDT on Friday, Oct. 9, with maximum sustained winds near 45 mph, and a tropical storm watch covers the Southern California coast from the U.S.-Mexico border to the San Diego-Orange County line. The watch means tropical-storm-force winds are possible along that stretch of coast late Saturday night or early Sunday, Oct. 11.
The Southern California watch sits alongside outright tropical storm warnings for northern Baja California. Rachel is expected to strengthen a little more before it reaches the coast, then fall apart quickly over the mountains.
Watch and Warning Lines in NHC Advisory 52
The National Hurricane Center’s Advisory Number 52, issued at 8 p.m. PDT with the storm at 23.8 degrees north and 123.3 degrees west, keeps the Southern California watch in place and adds a new layer on the Mexican side. Tropical storm warnings now cover the west coast of Baja California from San Jose de las Palomas to the U.S.-Mexico border, and the east coast from Isla San Luis to Puerto Penasco, after Mexico upgraded the eastern Baja watch to a warning. A separate watch covers the east coast from Bahia de los Angeles to Isla San Luis and northwest Mexico from Puerto Libertad to Puerto Penasco.
Earlier in the day, Intermediate Advisory 50A at 11 a.m. PDT had listed winds of 50 mph and a central pressure of 994 millibars. By 8 p.m. the winds had eased to 45 mph and the pressure had risen to 995 millibars, a sign that the shallow, ragged storm had briefly lost ground.
A Northeast Track Toward Baja and the Peninsular Ranges
Rachel is no longer drifting. NHC Advisory 52 has it moving northeast at 9 mph, up from about 5 mph nine hours earlier, and the forecast calls for it to accelerate northeast and then north-northeast as it is pulled along the front of a deepening upper-level trough. In Discussion Number 52, forecaster Adams wrote that the storm should move inland over northern Baja California late Saturday or early Sunday.
The timetable in that discussion puts the center near 28.9 degrees north, 118.1 degrees west at the 24-hour mark, roughly 8 p.m. PDT Saturday and just off the Baja coast, and near 33.9 degrees north, 116.0 degrees west at 36 hours, about 8 a.m. PDT Sunday, as a post-tropical system over the interior. Intensity is forecast to rise to 50 knots, or 60 mph, at 24 hours despite increasing wind shear. Forecaster Kelly, in the earlier Discussion 50, had described the same approach to northern Baja or southern California.
Discussion 52 adds a detail that matters for San Diego: the low-level center is likely to dissipate over the Peninsular Ranges, while the mid-level circulation carries on into the southwestern United States.
Surf, Rip Currents and Coastal Flooding on the San Diego Beaches
For the coast, water may matter before wind does. NHC says swells from Rachel will build along Southern California and northern Baja California through the weekend, producing life-threatening surf and rip currents plus moderate to isolated major coastal flooding into early next week.
The National Weather Service office in San Diego laid out the local numbers in its area forecast discussion issued at 9:47 p.m. PDT on Oct. 8: a new south swell arriving Sunday with surf of 5 to 7 feet and sets to 9 feet on south- and southwest-facing beaches, easing to 3 to 6 feet Monday and Tuesday. Morning high tides near 7 feet, combined with the swell, keep a coastal flood advisory for the Orange and San Diego County coasts running until 2 p.m. PDT Tuesday, according to that discussion. The office also noted that its confidence in rainfall totals was low because everything depended on Rachel’s track, with some model members, including the 12Z GFS, pulling the storm farther north toward the Southern California Bight.
Wind and Rain Once Rachel Moves Inland
Within the watch area, NHC expects tropical storm conditions to be possible starting late Saturday night or early Sunday, and strong, gusty winds to spread over the interior Southwest, especially on higher terrain, into early next week. NWS San Diego’s Oct. 8 discussion expected stronger southwest to west winds Sunday, with marine gusts of 20 to 30 knots.
Rain is the lesser threat at the coast and the larger one inland. NHC’s rainfall guidance is 1 to 3 inches for parts of Baja California and 1 to 3 inches for the Southwest, with locally up to 5 inches. The Weather Prediction Center’s excessive rainfall discussion, updated at 0102 UTC on Oct. 10, has a Moderate Risk of flash flooding for portions of southern California on Saturday, with rain of 1 to 3 inches possible in the southern California mountains.
The next intermediate advisory is due at 11 p.m. PDT, and the next full advisory at 2 a.m. PDT on Saturday, Oct. 10. NHC’s forecast peak of 60 mph at the 24-hour mark, set against the 45 mph recorded at 8 p.m., is the figure that separates a gusty Sunday on the San Diego coast from a damaging one.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
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