MAINE, USA — A geomagnetic storm is ongoing, with peak intensity expected to happen late Wednesday evening. While this storm is not necessarily something we can feel, it's certainly something we can see.
If you look up to the north tonight, keep an eye out for the aurora borealis, otherwise known as the northern lights.
There's a catch, though. The forecast calls for clouds tonight. The biggest hurdle to seeing the aurora in Maine or New Hampshire will be sky conditions.
The Forecast
If you're interested in trying to see the aurora on Wednesday evening (and let's be honest - who ISN'T interested?), keep a close eye on the clouds. Any breaks in the cloud cover will be the key to seeing the northern lights.
This forecast is not an optimistic one, unfortunately.
Given the placement of our upper level disturbance, it seems that overcast skies are a lock for the western mountains, central highlands, and northern Maine.
The story will be a little bit different in southern Maine, though.
Partial clearing is expected southwestern Maine tonight as the downsloping wind helps to dry out the atmosphere and leads to breaks in the clouds.
Expect to see some breaks in the clouds around 9 or 10 p.m. in parts of York, Cumberland, Kennebec, southern Oxford, and Androscoggin counties.
With the moonrise not happening until 12:35 a.m. in Portland, that gives a couple of hours with no extra light pollution to get a glimpse at the aurora.
The lines above represent the southern extent of the storm's strength. This has a direct implication for aurora visibility.
For example, the Kp7 line that runs from Fryeburg to Lewiston to Lubec is where the geomagnetic storm is strongest at magnitude G3. This is where the lights will be most visible, if the clouds break up enough.
Bottom Line
This is a complicated forecast for something that is fairly rare. Given the cloudy forecast, it could be a total bust for us locally.
If not, though, the late moonrise and active space weather could treat us to a wonderful light show.
For more info on the aurora, check out this link from the NOAA's Space Weather division.
For more forecast info as we get closer, follow me on Twitter, @MikeSliferwx.
