A wave of wintry weather swept across New England on Wednesday, bringing a mix of snow, ice, sleet and freezing rain that led to hazardous driving conditions and widespread school closures, while forecasters warned of additional storms later in the week.

Rain, snow and slush coated roads across the region, prompting dozens of school districts to either close or delay opening. Although snowfall totals were expected to be modest, officials said icy roads made it too dangerous to operate school buses safely.

Some areas saw around a tenth of an inch of ice accumulation—enough to create slick and dangerous conditions, though slightly below levels typically associated with widespread power outages. Even so, several thousand customers lost electricity, mainly in Maine, with hundreds more affected in Massachusetts.

School officials cited safety concerns as the main reason for closures. Administrators at Maine Regional School Unit 21 in Kennebunk said icy conditions along both morning and afternoon bus routes posed risks to students and staff.

All six New England states were placed under winter weather advisories by the National Weather Service, which also issued hazardous outlooks for northern regions that may face more severe winter storms in the coming days. Forecasters warned that heavy rain followed by falling temperatures could further worsen road conditions later in the week.

Transportation officials in Maine, New Hampshire and Massachusetts reported numerous crashes and vehicles sliding off roads, though no serious injuries had been reported by late Wednesday morning. Several regional airports, including Boston’s Logan International Airport, were forced to deice aircraft due to the snow and ice.

In parts of southern Maine, winter weather advisories were issued even though snowfall was expected to reach only about two inches. Meteorologists said the combination of freezing rain, sleet and snow justified the warnings. Another weather system is forecast to bring rain late Friday into Saturday, followed by a chance of snow extending into Sunday.

Patriotic crystal ball to light up Times Square on New Year’s Eve as US 250th anniversary begins

Officials said such mixed winter precipitation significantly worsens travel conditions, even when snow totals remain relatively low.