Long Island’s weather roller coaster will continue.

After this past week saw a mixed bag of weather events, including temperatures dipping into the teens, a wintry mix of snow, freezing rain and rain, this week will start off with yet another change. Temperatures are expected to be 10 to 15 degrees above normal Sunday, with a high of 57 degrees, said National Weather Service meteorologist Brian Ciemnecki.

The forecast for Sunday calls for rain but milder temperatures in the mid 50s by noon. Normal for this time of year in Islip is 42, Ciemnecki said. On Saturday, an average of 3 inches of snow fell across the area followed by freezing rain and finally rain.

By Sunday night, temperatures will fall back to the low 20s with black ice possibly developing into Monday when water left by melting snow refreezes.

“When the rain ends we’re going to start cooling off again,” Ciemnecki said.

The changing weather pattern is because multiple fronts have moved into the area recently, Ciemnecki said.

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Late in the week cold air arrived with an arctic front that moved across the area. On Friday night a warm front arrived from the South that started pushing back into the region, warming temperatures.

“As that warm front moved into our area, a wave of low pressure developed,” Ciemnecki said. “With cold air still in place the combination created precipitation, which is why we got the snowfall. As the front moved through and that wave of low temperature started to move away, temperatures rose, precipitation started to transition from snow to freezing rain to rain.”

The wet and icy conditions made for hazardous driving.

Suffolk County police Commissioner Timothy Sini early Saturday urged motorists to stay off the roads. He said there were about 100 accidents reported on Long Island’s roads starting overnight Friday, a number that is not atypical for this time of year. None of them involved any major injuries, he said.

In Nassau County, westbound lanes of the Long Island Expressway at Exit 42 were reopened about 8 a.m. Saturday; authorities had closed them because of a crash at the entrance to the Northern State Parkway in Jericho, Nassau County police said.

Temperatures are expected to rise through part of Sunday along with rain, then another cold front is expected.

Through Thursday a mix of sun and clouds is expected with temperatures in the low to mid-40s. Mostly cloudy skies and a chance for periods of rain are possible on Friday, when highs are expected to reach 48 degrees. Overnight lows for later week will be in the low to mid-30s.

Ciemnecki says the early forecast for Christmas Eve looks dry with temperatures a degree or two above the normal of 45, but no snow.

With Sarah Armaghan