INDIANAPOLIS (AP) - A mix of freezing rain and snow moving across Indiana slowed traffic and prompted dozens of school districts to cancel classes.

The National Weather Service issued a winter storm warning through Friday for most of southern Indiana, with up to 5 inches of snow and some ice accumulation. Slick roads and lower snow amounts were expected in central and northern Indiana.

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Numerous school districts from all over the state of Indiana closed on Friday. Vehicle slide-offs snarled traffic on highways in the Indianapolis area, but no major crashes or significant injuries were immediately reported Friday morning.

At least a dozen counties across southern Indiana have issued travel advisories, recommending only essential travel, such as to and from work or in emergency situations.