Massachusetts · 5 towns compared
Northern lights in Massachusetts: tonight’s chance
Massachusetts needs a strong storm everywhere; the Berkshires and the Quabbin country give it a dark place to watch.
Tonight at Boston, MA
…
Reading the SWPC Kp forecast and the cloud forecast…
| Kp forecast during the dark hours | not yet forecast |
|---|---|
| Kp needed here | 7.0 (G3 strong) |
| Cloud cover in the dark hours | loading |
| Dark sky (Sun 18° down) | 7:38 PM to 5:22 AM EDT |
| Moon | 12% lit |
| Right now, OVATION (30 to 90 min) | loading or unavailable |
| Magnetic latitude (AACGM) | 49.9° |
Hour by hour, EDT
7 PM
Kp –
– ☁
No
8 PM
Kp –
– ☁
No
9 PM
Kp –
– ☁
No
10 PM
Kp –
– ☁
No
11 PM
Kp –
– ☁
No
12 AM
Kp –
– ☁
No
1 AM
Kp –
– ☁
No
2 AM
Kp –
– ☁
No
3 AM
Kp –
– ☁
No
4 AM
Kp –
– ☁
No
5 AM
Kp –
– ☁
No
Rules checked · Built by Radif Partners · How the answer works
- Kp to see it from Boston
- 7.0
- Storm level needed
- G3 (Strong)
- Kp for aurora overhead
- 8.0
- Most clear dark hours
- November
Massachusetts sees the northern lights only in strong geomagnetic storms. In the AACGM model the state lies around 49.9 degrees magnetic latitude, close to the G3 line that NOAA's storm scale draws at 50 degrees: Pittsfield, in the Berkshires, needs a planetary Kp of about 6.9, Springfield and Worcester about 7.0, Boston 7.0 and Barnstable, on Cape Cod, 7.2. Those are G3 storms, which NOAA counts at about 200 per eleven-year solar cycle, many of them in daylight or under cloud for New England. The differences inside the state come less from latitude than from light: the Boston metro area fills the eastern sky, while the hill towns of the west are dark. Pittsfield's NASA POWER cloud amount ranges from 51% in September to 74% in December. The tool opens on Boston; type your own town or ZIP code.
A state at the G3 line
From Pittsfield to Barnstable, Massachusetts spans little more than a degree of magnetic latitude, and its thresholds run from Kp 6.9 to 7.2. All of them mean a strong storm. When SWPC issues a watch for G3 conditions, the state is in play; for anything weaker, the drive north into Vermont, New Hampshire or Maine is the realistic option. Those storms usually follow a fast coronal mass ejection one to three days earlier, which leaves time to plan the evening.
What Kp does this town need?
Kp to see aurora from here
6.9
| Magnetic latitude (AACGM) | 50.5° |
| Kp for aurora overhead | 7.8 |
| Storm level | G3 Strong |
| How often that level comes | about 130 days per 11-year cycle |
View line: the more southern of the SWPC oval rule and the NOAA G scale latitudes at each Kp.
West is dark, east is bright
The Berkshires and the hill towns of western and north-central Massachusetts are the darkest part of the state. Ridges such as those around Mount Greylock and the open farmland of the upper Connecticut valley give views to the north without the glow of big cities. The country around the Quabbin Reservoir, a large protected watershed in the center of the state, is another dark zone close to Worcester and Springfield. East of Interstate 495, the Boston metro area lights the sky in every direction; a northern horizon there is never truly dark.
When the storm comes in daylight
Many strong storms peak while it is day in New England, and the aurora is invisible however high the Kp. A storm that starts in the afternoon can still be strong after dark, or it can fade. The hour strip of the tool rates each hour of the coming night with the Kp of its three-hour block, so it shows at a glance whether the forecast peak falls in the evening, in the middle of the night or outside the dark window altogether.
Coastal nights
On the coast, the sea offers dark horizons to the east and south, but the aurora is in the north, and the north shore of Massachusetts Bay faces the wrong way. Cape Cod's bay side looks north across the water toward the lights of the South Shore. Coastal fog and low cloud are frequent in late spring and early summer. The Boston page details the city's options, and the New Hampshire page the closest darker country to the north.
Kp needed across Massachusetts
| Town | Magnetic latitude | Kp to see it | Kp overhead | Storm level |
|---|---|---|---|---|
| Pittsfield | 50.5° | 6.9 | 7.8 | G3 (Strong) |
| Worcester | 50.0° | 7.0 | 8.0 | G3 (Strong) |
| Springfield | 50.0° | 7.0 | 8.0 | G3 (Strong) |
| Boston | 49.9° | 7.0 | 8.0 | G3 (Strong) |
| Barnstable | 49.1° | 7.2 | 8.4 | G3 (Strong) |
Darkness and clouds by month in Boston
| Month | Dark hours | Dark sky, 15th | Mean cloud | Clear dark hours |
|---|---|---|---|---|
| January | 11.3 h | 6:15 PM to 5:30 AM | 62% | 4.3 h |
| February | 10.2 h | 6:50 PM to 5:05 AM | 61% | 4.0 h |
| March | 8.9 h | 8:24 PM to 5:20 AM | 61% | 3.5 h |
| April | 7.2 h | 9:07 PM to 4:20 AM | 61% | 2.8 h |
| May | 5.4 h | 9:56 PM to 3:23 AM | 64% | 1.9 h |
| June | 4.3 h | 10:36 PM to 2:52 AM | 62% | 1.6 h |
| July | 4.8 h | 10:25 PM to 3:15 AM | 55% | 2.2 h |
| August | 6.5 h | 9:32 PM to 4:05 AM | 53% | 3.1 h |
| September | 8.3 h | 8:29 PM to 4:49 AM | 51% | 4.1 h |
| October | 9.8 h | 7:35 PM to 5:24 AM | 59% | 4.0 h |
| November | 11.0 h | 5:59 PM to 4:58 AM | 60% | 4.4 h |
| December | 11.5 h | 5:53 PM to 5:25 AM | 63% | 4.2 h |