Many are already threatened by tree limbs overburdened by last week's ice and snow.
When the forecast calls for a half inch or more of ice, PECO goes into emergency prep mode.
They've called in extra crews, and they have all employees prepared to pitch in.
They still remember the nightmare of January 7, 1994. Three inches of ice coated the power lines, knocking out service to over half a million customers for days.
That's why they're urging customers to get ready now for the possibility.
"We want customers to prepare now, so they have the supplies that they need in their home," PECO Communications Manager Cathy Engel said.
That means flashlights on every floor of the house and plenty of batteries. Lanterns are much safer than candles.
Many people will turn to generators, but they have to be used safely.
Don't run them indoors or in an attached garage.
And don't plug into a regular household outlet.
Also, to protect your home and stay warm, open your faucets slightly to prevent frozen pipes.
Never use a gas range or stove for heat.
In the daytime, open your blinds to let the sunshine in and close them at night to minimize heat loss.
And if you have downed wires near your home, stay clear, even if they're not sparking.
Also, keep this number handy to report an outage: 1-800-841-4141. For more tips you can go to PECO's Storm Center.