The Ultimate Philly Weather Forecast

Think the weather we’ve seen in the last couple of years has been crazy? In the next few decades, Philadelphia could transform from a Northern city into what feels like a Southern one. And that could change everything about who we are.


Let’s begin with the Doomsday Scenario.

For the record, that’s my phrase, not Katherine Gajewski’s.­ But as Philadelphia’s director of sustainability starts to talk about what would happen if we had, say, a couple weeks straight of 100-plus-degree weather—which might not be such a crazy scenario in the decades ahead—you can understand why my brain starts to shift into Book of Revelation mode.

For starters, explains Gajewski, the whip-smart 31-year-old brunette hired by Michael Nutter three years ago to turn Philly into the greenest city in America, there’d be all those people who couldn’t breathe because of the choking air quality: the elderly, kids with asthma, folks with other respiratory issues and heart problems. Even worse is what would happen when all three million of us who live in the eight-county region cranked up our air conditioners—day after day after ungodly hot day—in attempts to stay cool.

“When you project out what happens when you have a high heat day,” Gajewski says, looking serious as she sits this December afternoon in a city government office on Market Street, “people are using air-conditioning, you’re maxing out the grid system, you’re potentially going into a blackout or brownout. In the United States, our electrical infrastructure is pretty outdated. And so you’re looking at systems that can’t withstand a lot of that stress.”

The power outages are where things really start to get fun. Because without power, people not only can’t run their air conditioners—more breathing issues!—but they also can’t run their refrigerators. Which means you’re going to have a whole lot of spoiled food. Which means eventually, you’re not going to have enough food in general. Which means … well, it doesn’t take Michael Crichton to conjure up what happens when you have a few million hot, angry, hungry people trying to figure out where their next meal is coming from. You see why I hopped aboard the fast train to Doomsday, right?

All of this is hypothetical, of course—conjecture piled on top of speculation layered on top of supposition. But it’s Gajewski’s job to think about these things, as well as what else can go horribly wrong if Philadelphia really is, in fact, starting to heat up. As she puts it, “We don’t know exactly what kind of temperature increase we’re looking at, but we need to look at a range of scenarios. And be prepared for each of them.”