Chance of West Coast Cyclones Rises as Seasons Grow Stronger

Hurricane Hilary, which developed on August 17 off the Western coast of Mexico, made landfall in Baja California as a tropical storm Sunday. Despite weakening in the process, it still caused heavy rains and flooding in Southern California and has moved into Nevada. One person died in Mexico.

It was the first tropical storm to hit California in 26 years, diverting attention away from this year's rather subdued Atlantic hurricane season to its Pacific counterpart, which has in the past dominated coverage. But as climate change is making extreme weather events more likely and more severe, the Pacific season has grown stronger. This is despite the fact that the cooler Pacific waters and the ocean's wind patterns generally make hurricanes less likely as well as lessening the possibility for them to make landfall.

Information from the National Hurricane Center at NOAA shows that while in the 1990s, an average year would see 5.3 tropical storms and 9.5 hurricanes in the Pacific, that was up to 7.2 storms and 10.7 hurricanes in the 2010s, upping the average number of cyclones per year from 14.8 to 17.9. 2023 so far has seen six Pacific hurricanes - of which Hilary was the only landfalling one - compared to just one Atlantic hurricane (Don). Three tropical storms in the Atlantic - Gert, Emily and Franklin - are currently active.