As of 8:00 a.m. PDT on Friday, September 23, 2011 (NHC Advisory #10): Hurricane Hilary remains a Category 4 hurricane, with maximum sustained winds of 145 mph. Hilary is currently moving west (275°) at 9 mph, and is expected to continue in that direction during the next 48 hours.
During the next two days, Hilary is forecast to remain a major hurricane as she continues to track over very warm waters. The hurricane is expected to enter the Southern California swell window on Monday at Category 2 strength, at which point the forecast models diverge, with some predicting a recurvature towards Mexico, and others a continued WNW track. The official forecast splits the difference, but may be adjusted to the north (or even northeast) later today.
At this point, the majority of swell generated by Hilary is being pushed west into the Pacific, however some 12-second south-southeast swell (165°) is visible in the Point Loma forecast for next Wednesday and Thursday. Nothing substantial at this time, with swell heights currently topping out at 2 feet.
However, if Hilary turns north once she enters the swell window, there is potential for additional size depending on Hilary’s movement and intensity. Cooler sea surface temperatures in the region mean a weakening trend is expected, but a northerly track would allow Hilary to pump her remaining energy into the water at a favorable angle, meaning swell heights would be larger than currently forecast.
We’ll have to wait until Sunday or Monday to see what Hilary does, but the swell arrival time is looking like late Wednesday into Thursday.