BOSTON - There's a chance that the northern lights could make an appearance over Massachusetts tonight, and the aurora borealis forecast says the possibility of seeing the colorful display will continue for the next several nights in New England.

The region was treated to a once-in-a-generation northern lights display back in May. And over the last few days, there have been multiple coronal mass ejections from the surface of the sun.

Two of these "CMEs" ejected out of Sunspot AR3842, a big hole in the lower center of the sun. These ejections took place when the active sunspot was facing directly at Earth.

Northern lights possible over Massachusetts

Therefore, we are now "on alert" for a potential geomagnetic storm and possible auroras over the next few nights.

Since the sun is 93 million miles away, it takes a few days for the CMEs to reach Earth.

Predicting the speed, size and intensity of these CMEs is extremely difficult, much harder than forecasting the weather.

Therefore, we cannot really know the exact impact it will have on Earth until it reaches some of our outermost satellites which are located about a million miles from Earth's surface. This gives us less than an hour's "heads up" as to the exact magnitude and impact of each wave of CME.

Scientists are typically able to get an initial indication (estimate) almost immediately after the explosion on the sun's surface.

The two flares of interest were measured at X7.1 and X9.1, quite high on the solar flare scale and plenty strong enough to produce mid-latitude auroras.

What causes the northern lights?

An aurora borealis occurs when these large and dense solar ejections collide with the molecules in the Earth's upper atmosphere. Our magnetic field causes the particles to be largely re-routed toward our Poles, hence why it is so much more typical to see the northern lights that farther north you live.

When we have large ejections and strong geomagnetic storms the lights can seen farther south.

These storms are measured on a "K index." Typically, when the K index is 7 or higher that indicates a higher chance of auroras at lower latitudes (including New England). The forecast for the next few nights is currently right at 7.

How to see the northern lights

If you want to optimize your chances to see the northern lights, you need to find an area with the least amount of light pollution (dark sky). Also, give yourself a view of as much open sky as possible without any obstructions. Other than that, good luck. More often than not, aurora hunting in New England ends in disappointment.

Weather-wise your odds are better Saturday night as there will be periods of clouds Friday night.

Finally, if you are able to snap some pics tonight, we would love to see them. Send them to weather@wbztv.com

A word of warning: most of the images you see of the northern lights online and on TV are using long exposure, very expensive cameras. Seeing an Aurora with the naked eye likely won't be nearly as vivid or deep in color but, it is still well worth the effort.