Northern lights Pennsylvania tonight
Pennsylvania at roughly 51°N magnetic latitude needs Kp 4 from dark sky sites. Cherry Springs State Park in north-central Pennsylvania is one of the best-known dark sky parks in the eastern USA - Bortle 1 conditions on a 700 m plateau. The state sits at a productive latitude for regular aurora events. Best season: September to April.
Aurora visibility - Pennsylvania
Unlikely tonight
Kp 1 is well below the Kp 4–5 threshold needed for aurora to be visible from Pennsylvania.
Current Kp
1
of 9
7-day outlook for Pennsylvania
Today
3 Jun
Tomorrow
4 Jun
Fri
5 Jun
Sat
6 Jun
Sun
7 Jun
Mon
8 Jun
Tue
9 Jun
Based on CME arrival predictions from NASA DONKI. Arrival times ±6 hours.
auroratonight.space
What Kp is needed here?
Pennsylvania sits at a magnetic latitude of approximately 51°N. The Kp index - a global measure of geomagnetic activity on a scale from 0 (quiet) to 9 (extreme storm), updated every 3 hours - needs to reach Kp 4–5 before the auroral oval expands far enough south to be visible from here.
At Kp 4–5, visibility is possible from Pennsylvania but skies need to be clear and dark. Cloud cover and light pollution remain the main obstacles even when Kp is high enough.
Best dark sky sites near Pennsylvania
Light pollution is the biggest obstacle after cloud cover. These sites give you the best dark northern horizon within reach.
Cherry Springs State Park
Get directions ↗Designated an International Dark Sky Park in 2018, Cherry Springs sits at 680 m on a high plateau in Potter County with Bortle 1 conditions on the main observation field. The state forest surrounds the park for 30 km in all directions. The north-facing side of the observation field gives an open northern horizon. Cherry Springs is the best dark sky park in the eastern USA for aurora - at 41.7°N geographic (roughly 52°N magnetic), the Kp threshold is about Kp 4.
Tioga State Forest / Pine Creek Gorge area
Get directions ↗The state forest surrounding Cherry Springs gives Bortle 2 sky over a large area. Forest roads give additional dark sky positions beyond the park boundary. The Pine Creek Gorge - known as the Pennsylvania Grand Canyon - near Wellsboro gives north-facing gorge-rim positions with dark sky and dramatic foreground for photography.
Forbes State Forest / Laurel Highlands
Get directions ↗In the Appalachian ridge country southeast of Pittsburgh, the Laurel Highlands give Bortle 3 sky with north-facing ridge positions. Ohiopyle State Park and the ridges along the Youghiogheny River give accessible dark sky within an hour of Pittsburgh. The southern Fayette County ridges at 500-600 m face north across the river valleys.
Delaware Water Gap NRA (east Pennsylvania)
Get directions ↗The Delaware River valley between Pennsylvania and New Jersey gives Bortle 3 conditions in the gap between the two metro areas. The ridge tops on the Pennsylvania side face north. Accessible from the I-80 corridor. About 65 miles from Philadelphia and 130 miles from New York City, this is the closest practical dark sky escape for eastern Pennsylvania residents.
Best time to see the northern lights in Pennsylvania
Pennsylvania's aurora season runs from late September through to March, when nights are long enough for truly dark skies. The equinox months, September and March, bring a natural boost in geomagnetic activity, making them statistically the best of the season. Summer months bring too much twilight for aurora to be visible at this latitude.
Activity peaks around the September and March equinoxes, when Earth's magnetic field geometry is most favourable for coupling with the solar wind. Events during these two windows tend to produce the strongest displays of the year for observers at Pennsylvania's latitude.
April through August brings persistent astronomical twilight that washes out aurora completely. Even strong events (Kp 6+) remain invisible during this period because the sky never gets dark enough.
Other USA aurora forecasts
← USA overviewCompare nearby locations
Up to 4 locations
Related pages
USA Aurora Overview
State-by-state aurora forecast and Kp thresholds across the United States.
New York Aurora Forecast
Aurora forecast for New York, including the Adirondacks and upstate dark sky sites.
Maryland Aurora Forecast
Aurora forecast for Maryland with western mountain dark sky sites.
New Jersey Aurora Forecast
Aurora forecast for New Jersey, including the Pine Barrens and High Point State Park.
Kp Index Guide
What the Kp index means and how to use it to plan aurora viewing.
Aurora photographs from Pennsylvania
Aurora borealis over Pennsylvania
Public domain · Source
Aurora borealis over Pennsylvania
ISS Expedition 29 crew · Public domain · Source
Aurora borealis over Pennsylvania
ISS Expedition 29 crew · Public domain · Source
Aurora borealis over Pennsylvania
ISS Expedition 29 crew · Public domain · Source
Aurora borealis over Pennsylvania
The original uploader was 14jbella at English Wikipedia. · CC BY-SA 1.0 · Source
Common questions
Aurora viewing in Pennsylvania - Cherry Springs, Kp thresholds for Pittsburgh and Philadelphia, and the best dark sky sites in the state.
