Snow showers and squalls are possible into Monday evening in the Philly area

After one of the colder mornings of the year, snow squalls rippled through parts of the region Monday afternoon — along with an outbreak of cellphone weather alerts — and more squalls or snow showers were expected into Monday evening.

The National Weather Service warned heavier showers, or the more-intense squalls, could reduce visibility briefly to near blizzard levels and coat the ground.

“Snow shower and squall coverage continues to run greater than expected,” the weather service said Monday afternoon. The squalls seemed to strike randomly, and yielded to the sun almost as suddenly as they had arrived. A lot of people might have been left wondering what all the fuss was about.

But they showed their disruptive power in Schuylkill County. During a squall, a a massive pileup occurred on Interstate 81, with dramatic social-media videos showing multiple vehicles plowing into each other. In all, 40 were involved and that 24 people taken to area hospitals, said John Blickley, an official with the Schuylkill County Office of Emergency Management. The Associated Press quoted a county official as saying at least three people were killed.

No weather-related accidents were reported in the Philly region, but this was hardly just another spring day.

The ambitious daffodils and other plants enticed to bloom by the warmth of March are having quite a blue Monday.

Temperatures around daybreak dropped into the low and mid-20s — with no immunity for the Philly urban heat island or the Jersey Shore. Nor will the rest of the day be a day at the beach, with highs in the 30s, gusts as high as 30 mph, and wind chills in the teens and low 20s.

And temperatures Tuesday morning will be even lower.

Temperatures at mid-afternoon in Philadelphia were in the mid-30s: The lowest daily high for a March 28 was 35 degrees, set in 1877.

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“We’re talking about the polar vortex moving right across the Northeast,” said John Feerick, senior meteorologist with AccuWeather Inc.

The vortex, a band of strong, frigid winds in the high atmosphere that is a prime agent of extreme cold outbreaks, wasn’t much of a factor around here during the winter. The Arctic air-pressure patterns generally favored keeping the persistent cold to the higher latitudes, meteorologists said.

One symptom of that is the fact that the coverage extent of Arctic sea ice this season was a bit greater than it has been in most recent years, said polar scientist Judah Cohen, with Atmospheric and Environmental Research, in Massachusetts.

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This being spring, nothing cold can stay, but it will be impressive while it lasts. With winds dying down and skies clearing — ideal for overnight cooling — readings are due to tumble to the upper teens to low 20s early Tuesday.

“That’ll freeze anything,” said Jeff Lynch, grounds manager at Chanticleer Gardens, in Wayne. They will head back to the 20s early Wednesday.

Local horticultural experts recommend covering sensitive plants with sheets, burlap, or other light fabrics. The weather service isn’t issuing freeze warnings, said Amanda Lee, a meteorologist in the Mount Holly office. because technically the growing season — timed to the last-freeze date — hasn’t begun.

Temperatures will moderate some Tuesday and Wednesday with highs in the 40s, still 20 degrees or more below normal for the date.

March will end Thursday with lamb-like highs back into the 70s, but with a roar of thunder possible with showers.

Save for another round of flurries on Monday, no snow is in the near- or long-term outlooks, and that could well be it until the winter of 2022-23.

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“You never say never,” said Feerick. “As you get into April, it gets really hard. Everything has to line up perfectly.

“I would take the under on an inch of snow.”