After a six-week run of wintry weather that bumped some of the region’s seasonal snow totals past 40 and 50 inches, the region’s trees are about to impersonate Mummers as the atmosphere fast-forwards the calendar by six weeks.
Temperatures in Philly are due to hit 80 on Friday and Saturday for the first time since Oct. 10. That was Week 5 of the NFL season, back when the Eagles were 4-1.
While conditions might appear ideal for yard work and gardening, the soil might still be marinating in the melted snows, and Emelie Swackhamer, a horticulture specialist at the Penn State cooperative extension in Montgomery County, recommends a certain caution.
In the meantime, above the ground the bud-swollen trees are likely to take the cues from the blossoming warmth.
The magnolias already are showing off in the city, said Swackhamer, and other flowering trees, including the peach and cherry, are about to join the party.
“I would expect things to pop out,” said Paul Walker, a senior meteorologist at AccuWeather. “It will probably be a high pollen day.”
Walker is among the allergy sufferers, and the tree-pollen season is approaching its annual peak in the region.
On Thursday, tree pollen counts were “very high,” according to the Asthma Center, and conditions Friday – 80-ish, breezy, dry – should be ideal for pollen flight.
Hitting 80 in mid-April isn’t all that unusual in Philadelphia. The record for an April 13 – 89 degrees – is well out of reach, and the daily records from now until October are 90 or better.
“The unusual thing is how darn chilly it’s been this month,” said Walker. Thus far, temperatures at Philadelphia International Airport are averaging 6 degrees below normal, and 4.1 below since March 1.
The official low Wednesday, 29 degrees, marked just the second time in the last 25 years that an official subfreezing reading was recorded this late in April.
And like a stubborn common cold, the chill isn’t going away quite yet. Right now, it isn’t all that far away, having passed through customs and taking residence in southeastern Canada.
On Sunday it is due to slip south via a “back door” front, a staple of spring and so named because it moves northeast to southwest, as opposed to west to east.
Those fronts import chilly air from the north country and promote onshore winds from the Atlantic, where sea-surface temperatures are in the 40s.
Temperatures Sunday afternoon could be 20 to 30 degrees cooler than Saturday, with a nasty rainstorm to follow Sunday night into Monday. While precipitation has been on the light side so far in April, for the last 60 days it has been well above normal throughout the region, getting a boost from that sequence of nor’easters in March.
Swackhamer said the wetness could be an issue for weekend gardeners. “You need to be aware of soil conditions,” she said. “If the soil is wet, you can do a lot of damage.” She said if it feels like Play-Doh, “You don’t want to be tilling.”
Her recommendation: “This weekend people should be concentrating on cleaning out debris and pulling out perennial weeds.”
Ultimately, spring as we’ve known it should take hold. Walker said readings should return to normal by the middle or end of next week, but “normal,” at least around here, isn’t necessarily normal.