July 01, 2024
Steve Stulb/for PhillyVoice
A photo taken in Plymouth Meeting, Montgomery County, shows mammatus clouds during Sunday night's sunset, which followed a heavy storm that swept through the region.
The prize for an oppressively hot, humid and rainy Sunday was a spectacular sunset that cast a peculiar glow over the Philadelphia area and beyond.
Sunday's dusk stood out because of the unusual mammatus clouds that hovered in the sky after the storm broke. They form when cold air condenses at the base of a rain cloud. Heavy water and ice particles sink and heat up, leading to the appearance of drooping bulbs on the underside of the large storm cloud, according to the UCAR Center for Science Education.
If the timing is just right with a sunset, it can produce the brilliant effect seen Sunday night in much of the Delaware Valley and South Jersey.
Views like this with vivid color are a result of mammatus with the outflow boundary PLUS the sunset and angle of the sun hitting the ice crystals in the cloud(s) and producing this somewhat rare effect. More common to see this after a severe weather day, like today. https://t.co/U9N8wKWoFw
— Bobby Martrich | EPAWA (@epawawx) July 1, 2024
The ominous appearance of mammatus clouds is generally a sign that the worst of a storm has passed, although the instability in the atmosphere could still mean lightning, rain and hail are possible. The clouds are often associated with turbulence during flights. Sunday's storms contributed to disruptions and delays at Philadelphia International Airport.
On the bright side, people from across the region took stunning photos and videos of the sunset.
MAMMATUS ☁️over Center City, Philadelphia. @NBCPhiladelphia pic.twitter.com/7UeOOwdpfV
— Justin Godynick NBC10 (@JGodynick) July 1, 2024
8:45PM still with sunlight. And the sunset bouncing off the thick after storm clouds literally had the sky glowing yellow then red and made me feel like I was in a movie with CGI. pic.twitter.com/XePDWkm8ao
— wannabGM (@PhillyWannabGM) July 1, 2024
Pretty incredible sky in Philly tonight! I learned these are called mannatus clouds @phillywx pic.twitter.com/rE5OhlkXM5
— jos (@trader__jos) July 1, 2024
the mammatus clouds tonight in the Philly burbs were GORGEOUS 🤩 pic.twitter.com/OUqiUPq6lp
— (base)bail // 55-29 (@marshsbadomens) July 1, 2024
@6abcadamjoseph @CecilyTynan check out these clouds over Blue Bell, PA tonight! What kinds of clouds are they? Thanks for any details you can provide. pic.twitter.com/k5R6t2xJkJ
— Jill Short (@jillsaintclaire) July 1, 2024
A beautiful display of mammatus clouds outside of @6abc tonight! pic.twitter.com/nStJ7sxF5A
— Brittany Boyer (@Brittany_Boyer) July 1, 2024
Hey @6abcadamjoseph @CecilyTynan it looks like mammatus clouds in Chester County tonight! pic.twitter.com/Erei61lfqf
— John Paul (@JPaulOnAir) July 1, 2024
Here's a look at the National Weather Service forecast for the week.
Monday: Mostly sunny, with a high near 81. North winds around 15 mph, with gusts as high as 25 mph. At night, mostly clear with a low around 64.
Tuesday: Sunny with a high near 86. At night, partly cloudy with a low around 63.
Wednesday: Mostly sunny with a high near 86. At night, partly cloudy with a low around 70.
Thursday (Fourth of July): A chance of showers and thunderstorms after 2 p.m. Partly sunny, with a high near 92. Chance of precipitation is 30%. At night, mostly cloudy with a low around 74. A chance of showers and thunderstorms.
Friday: A chance of showers and thunderstorms after 2 p.m. Partly sunny with a high near 91. Chance of precipitation is 40%. At night, mostly cloudy with a low around 75.
Saturday: A chance of showers and thunderstorms. Mostly sunny with a high near 93. At night, a chance of showers and thunderstorms. Mostly cloudy, with a low around 74.
Sunday: A chance of showers and thunderstorms. Mostly cloudy with a low around 74. Mostly sunny with a high near 91. Chance of precipitation is 30%.
