If you're ordered to evacuate, keep in mind that it could be days -- if not weeks -- before you can return to your home. That means you're going to need important supplies to take with you, like your prescription medications and anything for your pets or small children.
And even if you can get home -- or if you don't evacuate -- it may be weeks before you have electricity or water.
Remember the long lines for water and ice immediately after Wilma hit South Florida in 2005? You don't want to be one of those unprepared victims, so make sure to plan early.
Officials say the bare minimum that you should have is enough food, water, and ice for three days -- especially now that FEMA says they won't be handing out ice. But of course, the more supplies you have, the better.
We've put together a list of some important items to buy before a storm hits. Many of these things can be stored for months or years in advance, so get them now or risk facing long lines or shortages when a storm threatens the Bay Area.