Hilary: Flood Risk for California, Nevada, and Arizona

Tropical Storm Watch Issued for 

Southern California

Rainfall forecast for Hilary.
Serious flooding likely with this storm.
It will be similar to Hurricane Kathleen in 1976

There are people who are going to make a great deal out of "the first" tropical storm watch for Southern California but tropical storm watches and warnings should have been issued for Kathleen and other storms. For more on Kathleen and its devastating effects, which were similar to the current forecast path of Hilary, go here.

While Hilary is now a major hurricane south of Baja (below), it will weaken as it approaches the United States. As of 9am MDT, it has 145 mph sustained winds. However, it will weaken considerably before reaching the United States. 

Hilary at 8:41am MDT

Below is the forecast path of Hilary.

Here are the color and intensity codes:

• M = major hurricane (sustained winds of 100 mph or stronger)
• H = hurricane
• S = tropical storm (winds 39 to 74 mph)
• Red = hurricane warning
• Pink = hurricane watch 
• Yellow = tropical storm watch
• Blue = tropical storm warning 
• Brown = radius of hurricane-force winds (75 mph or stronger)
• Amber = radius of tropical storm force winds. 

There will also be tornadoes but the threat area is too uncertain to pin down at this point. 

I expect peak wind gusts (enhanced by mountains) to be around 60 mph in Southern California with isolated stronger gusts. Here is where the flood watches (green) are currently in effect.

If you live in the green area, it is time to plan for what you would do if rising water occurs. The smartest thing you can do now is create a "go kit" -- a suitcase or bag with essential items you can throw in the car in case you have to evacuate on short notice. 

Commentary:

While rare, Southern California has been struck by hurricanes and tropical storms. In 1858, a hurricane came ashore in the San Diego area with 75 mph winds. There have been tropical storms as far north as Los Angeles. 

I have researched this topic considerably because I have a book manuscript (working title, Hollywood Hurricane) which is about the inevitable Cat 2 hurricane striking the Southland (no one is forecasting a hurricane now). 

Global warming has nothing to do with Hurricane Hilary (in spite of what another Hillary may say before all of this is over) forming, strengthening, or its path. That stated, I have no doubt the people who specialize in panicking people about global warming are both salivating and working overtime as Hilary moves north northwest. 

A Hurricane Hunter is going to investigate the storm this afternoon which will give us the additional data needed to make a more precise forecast.