WASHINGTON — Weather agencies around western Washington are warning residents to brace for severe thunderstorms and golf-sized hail on Wednesday.

With this weather pattern, power outages in some areas should be expected. Depending on the severity, these outages can last several hours or at worst-case scenario, a few days.

Here’s what you need to know

Power outages can cause an inconvenience at best and safety concerns at worst.

According to the Washington Department of Health:

Before a power outage

Register life-sustaining and medical equipment with your utility company.
Consider buying a generator. When installing a generator, follow the instructions carefully. Keep your generator outside and run a cord inside. Don’t connect your generator to main service panels—it’s dangerous! Be sure to place a carbon monoxide detector indoors. The DOH has generator safety tips here.
Make sure your disaster preparedness kit contains light sticks, flashlights, a battery-powered radio with extra batteries and a wind-up clock.
Have backup portable cell phone charges ready to go and already charged.
Have a safe alternative heat source and supply of fuel. Never burn charcoal or use a generator indoors.
If you own an electric garage door opener, know how to open the door without power.

During a power outage

Turn off lights and electrical appliances except for the refrigerator and freezer.
Even if it is dark, turn light switches and buttons on lamps or appliances to the “off” position.
Unplug computers and other sensitive equipment to protect them from possible surges when the power is restored.
Leave one lamp on so you will know when power is restored. Wait at least 15 minutes after power is restored before turning on other appliances.
Conserve water, especially if you use well water.
Never use gas ovens, gas ranges, barbecues or portable or propane heaters for indoor heating—they use oxygen and create carbon monoxide that can cause suffocation.
Candles can cause a fire. It’s far better to use battery-operated flashlights or glow sticks for lighting.
Using a kerosene heater, gas lantern or stove inside the house can be dangerous. Maintain proper ventilation at all times to avoid a build up of toxic fumes, and be sure to have a carbon monoxide detector.
Stay away from downed power lines and sagging trees with broken limbs.