document updated 2 months ago, on Mar 27, 2024

aurora forecasts

planning ahead

We're interested in seeing the aurora some time.

There are specific conditions needed for observing. There must be minimal cloud cover, and it must be dark (so avoid areas with light pollution, and avoid latitudes and months where there's midnight sun).

planning — very short lead time

The aurora are sometimes visible further south than they normally are. These are caused by coronal mass ejections — a mass of plasma that shoots through space.

Coronal mass ejections (CMEs) travel between 250 to 3000 km/s. This means that the amount of warning we have, between when a CME headed towards Earth is observed and it hits our atmosphere, is 14 hours to 7 days. However, most websites quote a range of 14 hours to 3 days.

So we would have a fairly short notice in which to book a hotel and arrange all the travel plans.

planning — avoiding midnight sun

The Arctic Circle is defined as the region that periodically receives a 24-hour period of daylight. However, regions just south of the Arctic Circle also receive a 'twilight' version of midnight sun.

Some relevant Wikipedia articles — midnight sun, polar night.

One way to check the specifics is to just look up the sunset (and nautical twilight and such) of a particular city on a particular day, using your favorite weather app. (TODO — is there a map or calendar or something that shows this at a broader perspective?)

In general though, avoid dates close to the Summer Solstice in June, in combination of when traveling north of 48° 33′ 46.7″N.

To see towns north of 48° 00' 00"N, look at this map, and find the latitude line that goes through the center of Lake Superior (more precisely, the one that's just south of Thunder Bay).

forecasts, long term (≥24 hours) is the place to be. — maybe even more useful

Google News

Other pages: [1]

"What is kp?" [1] [2] [3] [4]

forecasts, short-term (≤3 hours)

planning — possible places

Because we have such a short lead time, it may be advantageous to have some things pre-planned. Some places we could possibly stay: