LOS ANGELES (KABC) -- Los Angeles and Orange County are under a tropical storm watch for the first time in history as Hurricane Hilary makes its way toward Southern California.
Though Hilary was downgraded to a Category 2 storm Saturday afternoon, the National Weather Service said it'll still pack a punch with heavy rain likely to prompt flash flooding in some mountain and foothill areas, along with powerful winds Sunday into Monday.
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Many residents have already been stocking up supplies and groceries, but what exactly do you need and how do you know you're fully prepared? Here's what you need to know.
Make sure sure you and your family are prepared by having a well-thought out plan. Do you have all your emergency phone numbers written down? Are they stored in your cell phone?
Make sure you know how you and your family will get in contact with each other should an emergency occur. Also, take some time to review your insurance policies to make sure you have adequate coverage for your home and personal property.
The CDC also recommends you build a "plan by location." Do you and your family live in a home or an apartment building? Are you traveling and are stuck in an area under a warning? The CDC has a webpage dedicated to these plans that you can view here.
Make sure you have enough food, water, medication and other supplies to last you and your family for several days.
Before the storm, officials recommend you have the following items:
Consider adding the following items to your kit based on your individual needs:
The National Weather Service encourages everyone to familiarize themselves with the meaning of NWS watches and warnings. You can find a break down of each one here.
Local officials may tell you to evacuate or to stay in place so FEMA encourages people in any possible impact areas to pay close attention to local emergency information and alerts. Be sure to sign up for your local weather alerts and pay attention to the NWS.
Plan where you and your pet will stay in case you need to evacuate. Pets may not be allowed in some local shelters, unless they're service animals. Some disaster evacuation centers may not accept pets and other animals.
According to the Red Cross' website, when possible, Red Cross shelter workers will do all they can to accommodate domesticated pets comfortably, but depending on the situation, pets may need to be housed in a different location with support from animal welfare groups.
Work to find shelters or out-of-town friends or relatives where your pets and other animals can stay during an emergency. Track down boarding facilities or animal hospitals near you or maybe ask a neighbor you can trust who can check on your animals and can evacuate your animals if necessary.
As the saying goes, turn around, don't drown! Authorities strongly urge people to stay off bridges over fast moving water in areas experiencing flooding. Officials say the water can wash bridges away without warning.
Also, stay inside your car if it is trapped in rapidly moving water. If you're stuck, get on the roof if water is rising inside the car.
A storm can bring power outages so be sure to take inventory of your items that rely on electricity. If you have critical medical equipment, you can ask your power provider to put you on a list for priority power restoration, according to FEMA.
If you have a generator, remember to only use it outdoors and away from windows. If the power goes out, throw away any food that has been exposed to temperatures 40 degrees or higher for two hours or more, or that has unusual odor, color or texture.
If the power is out for more than a day, discard any medication that should be refrigerated, unless the drug's label says otherwise.
If you are near a stream or channel, be alert for any sudden increase or decrease in water flow or water that changes from clear to muddy. These can be signs that a landslide is coming.
Plus, be sure to avoid river valleys and low-lying areas and never cross a road with water or mud flowing. Plus, never cross a bridge if you see fast flowing water because it can grow faster and larger too quickly for you to escape. If you do get stuck in the path of a landslide move uphill as quickly as possible.
Be sure to check on your neighbors to see if they need any help preparing.
For more ways you can prepare now for a hurricane, visit ready.gov/hurricanes.
This article contains emergency planning information from FEMA, American Red Cross, the CDC and the National Weather Service.
City News Service also contributed to this report.