Fox News Weather Center

PHOTOS: Northeast Sunset Illuminates Mammatus Clouds Following Severe Storms

After severe storms trekked across the Northeast Tuesday night, skies were sprinkled with unique cloud formations against a dazzling sunset as the background.

A cold front intersected warm and humid air, setting off dangerous storms that produced large hail and destructive winds. However, as the storms retreated, many in the Philadelphia area were left with views of small, pillowlike clouds dotting the sky.

Known as mammatus clouds, the round, puffy appearance creates an intriguing sight.

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Mammatus clouds form when air sinks, unlike most clouds which form due to rising air. This results in the pouches of condensation that give these clouds their bumpy appearance.

The clouds then move along with the storms, pushed by the same wind moving the system, according to AccuWeather Chief Meteorologist Elliot Abrams. As the clouds form after a storm due to sinking air, they do not foreshadow potentially severe weather.

While the unique clouds offered a compelling sight as the storms ended, many were left to deal with damage left in the storms' wake.

NBC Philadelphia reported that four construction workers were injured after a house they were working on collapsed as the intense storms hit the area. Wind gusts reached up to 71 mph in the area at the time of the incident.

In Chester Heights, Pennsylvania, a man was trapped in his house after a tree crashed onto the roof. He had to be taken to a local hospital along with his wife and a firefighter attempting the rescue, NBC Philadelphia reported.

The strong gusts sent trees crashing onto roadways and other homes, knocking power lines down.

Hundreds of thousands were without power across Pennsylvania and New Jersey. More than 180,000 were still without power early Wednesday morning.