The northern lights show over Philly on Sunday and Monday was ambushed by timing and smoke
Northern lights in Philadelphia were a miss on Sunday, but there's slim hope for sightings tonight
For Philadelphians, a storm forecast that doesn’t quite work out is a familiar experience, but in this instance it canceled a potential cosmic magic show.
All the ingredients appeared to be aligned for a possibly spectacular display of the northern lights, perhaps as far south as Alabama for Sunday night.
A “rare” and powerful geomagnetic storm that would incite the aurora borealis did arrive — unfortunately, several hours before forecast.
And to Philadelphia and other areas around the country, that evidently made all, or at least most, of the difference, said Bryan R. Brasher, project manager at NOAA’s Space Weather Prediction Center.
Two “severe” geomagnetic storms — G4s on the 1 to 5 scale — were officially observed at 4 a.m. and 9:46 a.m. Philadelphia time. Brasher noted the postings on social media of images of the aurora early Sunday in Wyoming, which is two hours behind Philly; however no such images were evident anywhere near our region.
For obvious and less-obvious reasons, daylight is no friend to auroral displays, said Brasher. In addition, the lights would have been competing against veils of Canadian wildfire smoke.
Aurora sightings were reported north of here after sunset, and some spectacular images captured in the early morning hours of Monday were posted on social media from Montana, Idaho, and Colorado. Those may been the result of a “substorm,” Brasher said.
Later Monday morning, a “major” G3 storm was detected; however it was unlikely to be powerful enough to turn on the lights over Philly, he said.
The space weather center predicted the show might come tantalizingly close to the region Monday evening. Unfortunately, the layer of smoke appeared to have thickened, said Paul Fitzsimmons, a meteorologist with the National Weather Service in Mount Holly, and was expected to persist.
There’s a reason the agency calls their outlooks “experimental.” They are very much subject to change, given that they are based on material arriving from the sun interacting with earth’s geomagnetic field.
“We used to say we’re about 50 years behind the meteorologists,” said William Murtagh, longtime program coordinator at the space weather center. “I remind the meteorologists, ‘You guys got the first 10 miles. I’ve got the other 93 million.’”
What causes the aurora borealis?
Solar storms — commonly called sunspots — can eject massive quantities of charged particles and magnetic fields that stream toward Earth at ultrahigh speeds.
That was the case Sunday. The interaction of the solar material from the so-called coronal mass ejection, or CME, and the magnetosphere created the colorful, undulating and pulsating curtains of light that some fortunate people got to observe.
The polar regions are the aurora’s most frequent venues; however, the stronger storms can drive them toward the midlatitudes, as was the case Sunday.
What happened to the lights Sunday?
Given the timing, it’s likely that over Philadelphia the lights were wasted on daylight and that persistent veil of smoke, said Tom Kines, senior meteorologist with AccuWeather Inc.
Sunlight would upstage the aurora, Brasher said, but it’s deeper than just the light. It’s better for the show if the geomagnetic storm develops after sunset.
On the night side of the planet, he said, the earth’s magnetic field behaves in such a way in darkness that it becomes more favorable to generating the lights.
Philly had its day (or night) in the lights in the fall
On rare occasions, it does all come together around here.
The lights did appear, albeit briefly, in October, rose-colored and purple-ish, and spectacular while they lasted.
And that was the first time they were visible around here in over 20 years.
Is that all there is?
Not necessarily, Brasher said. Sunspot activity peaks in roughly 11-year cycles, the most recent one beginning in 2019.
“We are still at the peak.” He said the sun isn’t quite as frisky as it was in 2024, but “solar activity remains elevated.
“We are likely to continue seeing more frequent and intense solar flares and CME storms over the next year or so.”
To monitor the aurora prospects, visit the Space Weather Prediction Center site, and its aurora dashboard, and check out the “Northern Lights Alert” Facebook page.