PHILADELPHIA (AP) — The Pennsylvania Department of Transportation has temporarily reduced speed limits to 45 mph on all interstates and other expressways in the commonwealth as a major ice storm approaches.

PennDOT is urging motorists to avoid unnecessary travel during the storm and urges anyone who has to drive to use caution.

The National Weather Service has issued an ice storm warning for much of eastern Pennsylvania north and west of Philadelphia. The worst of the glazing is expected between 3 a.m. and 9 a.m. Wednesday.

Forecasters say power outages are expected to due to ice breaking off tree limbs and wires, and the outages could be severe if the glaze exceeds three-quarters of an inch.

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