Extra

The U.S. Navy's Blue Angels will be roaring over parts of the Bay Area starting this afternoon as San Francisco Fleet Week gets under way. 

The squadron will be rehearsing between 1 p.m. and 5 p.m. to prepare for air shows on Friday, Saturday and Sunday. 

The annual aerial displays over the San Francisco Bay can be seen from San Francisco and parts of the East Bay, the Peninsula and Marin County. 

But as many Bay Area residents know, the Blue Angels are sometimes heard before they are seen -- the F/A-18 Hornets' startling rumble is often the first sign that they are nearby.  

While the noise can be scary to humans, it is terrifying to many animals.  

"On a weekend like this, Fleet Week, we advise people to keep animals indoors," San Francisco SPCA spokeswoman Krista Maloney said. 

Maloney said the sound of the fighter jets passing overhead makes dogs and other animals run and hide, and sometimes get lost. 

She advised those taking their dogs outside to keep them on a leash and equip the pets with an easy-to-track-down collar, tags, and a microchip in case they run off. 

"It's not a good time to go to the dog park when the Blue Angels are out," she said. 

Fleet Week officially started this morning with military personnel convening at Piers 30/32 to overview disaster preparedness, response and recovery in San Francisco. The air shows are part of a series of Fleet Week activities that includes a Parade of Ships sailing under the Golden Gate Bridge on Saturday morning and military ship tours along San Francisco's southern waterfront through Monday.