Stagnant air undermines progress torward clear air in Pittsburgh and Philadelphia.

Urban Heat Islands

Cities are almost always hotter than the surrounding rural area but global warming takes that heat and makes it worse.

Summers are getting muggier as the dewpoint temperature rises

Summers in most of the U.S. are already warmer than they were in the 1970s. And climate models tell us that summers are going to keep getting hotter as greenhouse gas emissions continue.

Philadelphia is the 17th fastest-warming city in the U.S.

Currently, Pennsylvania averages fewer than 5 dangerous heat days a year. By 2050, the state is projected to face more than 15 such days annually.

More than 310,000 people living in Pennsylvania are especially vulnerable to extreme heat.

As summers get hotter under the planet’s growing blanket of heat-trapping greenhouse gases, the worst of it will happen downtown rather than out of town. Climate Central’s new analysis of the Urban Heat Island effect in 60 of the largest continental U.S. cities makes it clear just how big the gap can be during the summer.

Pennsylvania is projected to see an increase in severity of widespread summer drought of approximately 50 percent by 2050.

62 percent of meterological stations in Pennsylvania are getting more winter precipitation as rain than snow.

In Pennsylvania, there are more than 430,000 people living in areas at an elevated risk of inland flooding.

56.1 million gallons of sewage spilled in Pennsylvania from Hurricane Sandy.

Across most of the country, the heaviest downpours are happening more frequently, delivering a deluge in place of what would have been routine heavy rain. 

The most extreme precipitation events have increased in every region of the contiguous states.

Atlantic hurricane season is seeing more major storms

Today, Pennsylvania has 7,000 people at risk of coastal flooding. By 2050, an additional 6,000 people are projected to be at risk due to sea level rise.

Sea level threats down to zip code

Type a coastal place name in Pennsylvania and find local projections, maps and potential impacts on people, infrastructure, and much more with our interactive tool.

Pennsylvania has the smallest proportion of its total area currently in the 100-year coastal floodplain. By 2050, the area is projected to double from 10 to more than 20 square miles.

Marcus Hook, PA and sea level rise

Philadelphia is suceptable to sea level rise.

What's Happening in Your Region?

New York

Sandy’s Surge Was Extreme. It Could Become Normal

The risk posed by future storms like Sandy is only going to increase due to climate change. The potential for stronger storms and rising seas mean Sandy-level flooding could could occur once every 23 years as opposed to once every 400... More

North Carolina

Sinking Atlantic Coastline Meets Rapidly Rising Seas

New research using GPS and prehistoric data has shown that nearly the entire coast is affected, from Massachusetts to Florida and parts of Maine... More


U.S. Airports Face Increasing Threat From Rising Seas

The threat isn't that sea level rise will gradually breach the defenses surrounding each airport. Instead, at least during the next few decades, scientists say that sea level rise will be more of an enabler of storm-surge flooding, making it easier for even minor storms to produce more damaging surges and flooding... More


Maryland: Rain Causes 82 Percent of All Sewage Overflows

Increasing heavy downpours, fueled by climate change, cause millions of gallons of sewage overflows nationwide.... More

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