For the first time in history, a tropical storm watch has been issued for southern California. Impacts are expected to begin arriving there by Sunday night.
Hurricane Hilary is currently a cat 4 storm, with maximum sustained winds of 145 mph. The storm will weaken substantially as it moves closer to southern California. Cooler ocean temps, which normally protect California, interaction with land, and an inhospitable atmosphere will combine to downgrade Hilary to a tropical storm by Sunday night’s impact to southern California.
The storm is expected to bring catastophic flooding to parts of the southwest U.S. In addition. the winds of this system will be stronger in the mountains, leading to widespread damage of forestland.
This will only be the third time southern California has been directly impacted by a tropical system. The last time this occurred was in 1939. They were impacted by the first one in 1858 and that was actually a weak hurricane and the one and only one we know of to ever hit there!
There have been several close calls, as the map below shows. Many of those on the map weakened below tropical storm status before moving across southern California.
This is a historical moment in weather history. Populations have increases dramatically in southern California over the past several decades, leaving many more people in danger from this storm. Thankfully, this storm is being well forecast and folks have time to take precautions. That will surely keep death tolls and property damage much lower than they would otherwise be.
Closer to home, the Atlantic is getting busy, too! Nothing is an immediate threat to the U.S., but that may change over the next week to ten days.
