Something fascinating and more than a little spooky is happening right now with Hurricane John in the eastern Pacific. The storm is undergoing rapid intensifcation, so rapid that it has developed what forecasters call a "pinhole eye"--an extremely tight eyewall contraction evident in the image above. The same thing happened when Hurricane Wilma put on a record burst of intensification last year, building up from a tropical storm into a Category 5 hurricane in just 24 hours.
The forecasters were more than a little surprised by Wilma's intensification, and they seem surprised by John as well. At 8 am PDT this morning, they called the storm a Category 1 hurricane with 70 knot (or 80 mph) winds. In 12 hours, they predicted, it would be an 85 knot (or nearly 100 mph) Category 2 storm.
Well, instead, it's now a 100 knot or 115 mph Category 3 storm, and they're predicting 115 knots or 133 mph winds (weak Category 4) within 12 hours. I guess we'll see whether John surprises them again...but note these key words from the current forecast discussion:
THERE ARE NO APPARENT ENVIRONMENTAL CONDITIONS WHICH SHOULD INHIBIT ADDITIONAL
Meanwhile the AP is reporting that John could possibly hit Baja, California. I don't know whether or not that's alarmist, but I certainly don't see it in the 5 day cone for this hurricane....apparently storms in the east Pacific have, on at least one historical occasion, come up to hit San Diego, but it's an extreme rarity as they usually curve westward out to sea.
Correction: I made a silly mistake: It's the Baja California peninsula we're talking about, which is actually part of Mexico....
Michael Chenoweth and Chris Landsea wrote a fun paper in BAMS about the great San Diego hurricane of 1858 - fascinating to me for the way they pieced the story together from old newspaper clips etc.:
Also (from memory so maybe slightly fuzzy on the dates here), a TS hit the L.A. basin in the 1930s and apparently a sizable hurricane a century earlier. If SST increases work their way up the coast enough, L.A. could find itself looking like LA.