Philly’s summerlike Sunday will shift to thunderstorms, with hail and a tornado possible

It’s officially spring in Philadelphia, but it’s going to feel a bit like summer today before shifting over to some winter chills Monday.

Blame an incoming cold front, which is expected to move in from the west sometime after 4 p.m. Severe thunderstorms are possible, complete with damaging winds, large hail, and the possibility of some isolated flooding.

Forecasters also said an isolated tornado is possible. Last week, two confirmed tornadoes touched down south of the city — one in central Delaware and on Maryland’s Eastern Shore. Both were EF1s on the enhanced Fujita scale, with wind speeds clocked around 100 mph.

“The severe weather risk is a little unusual in it being a little early,” said Ray Martin, a meteorologist and the National Weather Service’s Mount Holly observatory.

Before storms roll through, it will be unseasonably warm in and around Philadelphia, with temperatures reaching the mid-70s. That’s about 20 degrees higher than the normal average for this time of year, which is right around 55 degrees.

But thanks to Sunday night’s storm, temperatures will dip down into more springlike temperatures Monday, with the high reaching 50 degrees and a chance of some showers before 2 p.m.

This is more or less normal for Philadelphia this time of year, as cold air masses from the north collide with warming temperatures, creating storms along the battle lines. At least temperatures won’t mimic the 48-degree plunge we experienced in the city last week.

While daytime temperatures will feel normal most of the week, it will get cold at night, with Monday night temperatures forecast to drop to a winter-like 32 degrees.

If it doesn’t dip below freezing Monday night, it could by the end of the week, with a weekend low of 29 degrees currently forecast for Friday night.

Here’s an extended outlook for Philadelphia, according to the National Weather Service:

The good news is we’re almost out of the woods in terms of the bone-chilling temperatures Philadelphia experienced this winter.

The average last freeze in Philadelphia is March 30, while it extends into mid-April in the suburbs.

“The urban heat element is very real,” Martin said.

Snow is another story. 30.1 inches of snow and ice have dropped on Philadelphia this season, the most since 2013-14, when 68 inches fell across the city.

While there is no snow currently in the forecast, It’s certainly possible. Nineteen inches of snow fell in Philadelphia on April 3, 1915, and measurable snow has fallen in the city as late as April 27.