Northern lights in Pennsylvania tonight
The aurora forecast for Pennsylvania, hour by hour: the Kp index NOAA expects, how dark it gets, the Moon and the clouds, for the north of the state (Erie) where the odds are best.
Unlikely Tuesday, October 27
The highest Kp expected after dark tonight is 1.67. Erie (north Pennsylvania) needs about Kp 6 to see the aurora low on the northern horizon, and the sky cover forecast after dark averages 67%. The Moon is 94% lit.
| Time | Sky | Kp | Clouds | Moon | Chance |
|---|---|---|---|---|---|
| 7 PM | Twilight | 2.33 | 51% | down | Not dark yet |
| 8 PM | Dark | 1.33 | 35% | 9° | Unlikely |
| 9 PM | Dark | 1.33 | 38% | 19° | Unlikely |
| 10 PM | Dark | 1.33 | 28% | 29° | Unlikely |
| 11 PM | Dark | 1.33 | 57% | 40° | Unlikely |
| 12 AM | Dark | 1.33 | 76% | 51° | Clouds in the way |
| 1 AM | Dark | 1.33 | 92% | 61° | Clouds in the way |
| 2 AM | Dark | 1.67 | 83% | 70° | Clouds in the way |
| 3 AM | Dark | 1.67 | 81% | 73° | Clouds in the way |
| 4 AM | Dark | 1.67 | 87% | 69° | Clouds in the way |
| 5 AM | Dark | 1.33 | 81% | 60° | Clouds in the way |
| 6 AM | Dark | 1.33 | 84% | 50° | Clouds in the way |
| 7 AM | Twilight | 1.33 | 82% | 39° | Not dark yet |
Forecast from NOAA SWPC (Kp, 3-hour blocks) and the National Weather Service (sky cover), checked when this page was built. The page updates itself when it can reach our data feed.
What Kp you need in Pennsylvania
The farther north (in magnetic terms) you stand, the lower the Kp you need. From Erie, an aurora usually shows low on the northern horizon once Kp reaches about 6; overhead displays need about two steps more. A phone camera in night mode often records it one step earlier than the eye. How we estimate this: our method.
How often the aurora reaches Pennsylvania
Our own count from the official Kp archive: on how many nights each year the Kp index reached about 6 or more while it was dark at Erie. Clouds are not counted, so the real number of nights with a visible aurora is lower. Over the last 10 years the average was 2.4 nights a year; in 2025 it was 8.
Data: Kp index since 1932, GFZ Helmholtz Centre for Geosciences (Matzka et al., 2021), CC BY 4.0. Darkness computed by us for each 3-hour interval (Sun 12° or more below the horizon).
The next 27 days
NOAA's 27-day outlook has no day with a largest Kp near the 6 that Erie needs. The outlook repeats the Sun's 27-day rotation and cannot see sudden storms, so check the 3-day forecast too.
| Day (UTC) | Largest Kp | At Erie |
|---|---|---|
| Tue, Oct 27 | 2 | Unlikely |
| Wed, Oct 28 | 2 | Unlikely |
| Thu, Oct 29 | 2 | Unlikely |
| Fri, Oct 30 | 2 | Unlikely |
| Sat, Oct 31 | 5 | Unlikely |
| Sun, Nov 1 | 4 | Unlikely |
| Mon, Nov 2 | 3 | Unlikely |
| Tue, Nov 3 | 2 | Unlikely |
| Wed, Nov 4 | 2 | Unlikely |
| Thu, Nov 5 | 3 | Unlikely |
First 10 days shown. Full table: 27-day aurora forecast.
Where to watch in Pennsylvania
Pennsylvania has a famous dark sky spot in Cherry Springs State Park, and the north central forests around it are among the darkest in the East. Erie also has a view north across Lake Erie. Philadelphia and Pittsburgh need strong storms and a long drive.
Use open fields in the Pennsylvania Wilds or a north-facing Lake Erie beach.
- Cherry Springs State Park: certified dark sky park in Potter County, north central Pennsylvania
- Presque Isle State Park: Lake Erie peninsula park in Erie
- Allegheny National Forest: national forest in northwest Pennsylvania
Nearby states
Questions people ask
Can you see the northern lights in Pennsylvania?
Yes, on active nights. From Erie it takes about Kp 6, which happened on about 2.4 nights a year over the last 10 years (before clouds).
What time is best?
Usually between 10 pm and 2 am local time, when the sky is fully dark and your location faces the night side of the auroral oval. Storms can bring it earlier or later.
Which way should I look?
North, toward a low, open horizon away from city lights. In strong storms the aurora can climb higher or appear overhead.
Is this an official forecast?
No. It is our estimate built from NOAA's Kp forecast, the National Weather Service sky cover forecast and the Sun and Moon positions. It is not a promise.
Sources: Kp forecast and 27-day outlook: NOAA Space Weather Prediction Center (public domain). Sky cover: National Weather Service (public domain). Kp archive: GFZ, CC BY 4.0. Coordinates: U.S. Census Bureau Gazetteer. Magnetic latitude: our calculation from the IGRF-14 model of Earth's magnetic field. Sun and Moon: Astronomy Engine. Unofficial estimates, not a guarantee.
Page checked: October 27, 2026.