The best month to see the northern lights

Aurora activity is set by the solar wind, which no one can forecast months ahead. What you can plan is when the sky is dark enough, and SWPC adds one seasonal tendency: larger geomagnetic storms, and thus better auroras, tend to occur near the equinoxes, in March and September.

The other planning input is the moon. It follows a 29.5 day cycle, so every month has a darker half. The month you pick matters less than which nights inside it you choose; the month pages list new and full moon dates for each town.

The matrix gives hours of civil night, the sun at or below -6 degrees, on the 15th of every month of 2026. Each cell links to the full month page for that town, with every night of the month.

The far-north towns swing hard. Tromsø runs from 19.2 hours on December 15 to none from May through July. Fairbanks runs from 17.2 hours in December to none on the 15th of May, June and July. The lower 48 towns stay between about 6.5 and 14.5 hours all year: Minneapolis has 7.0 hours in June and 14.0 in December.

For Fairbanks, Yellowknife, Reykjavik, Anchorage and Tromsø, the equinox months combine SWPC's storm tendency with nights long enough to use. On September 15 Fairbanks has 9.2 hours of civil night and Tromsø 8.4. On March 15 the figures are 10.4 and 10.2.

Midwinter adds hours but not storm odds. December nights are the longest of the year there, which gives the most time to wait for activity. If your trip is short and fixed, a long December night can beat an equinox night with a few hours less darkness. The month pages, such as Tromsø in December and Yellowknife in September, show the trade-off night by night.

May through July is off the table at the high-latitude towns. SWPC's own tips say combining a summer vacation to the Arctic with aurora watching usually does not work. The midnight sun guide gives the exact no-darkness dates.

Duluth, Minneapolis, Seattle, Buffalo and Portland, Maine have civil darkness every night of the year. For them the month matters less than the storm. SWPC's equinox tendency still applies, so March and September carry a small edge, and winter nights give more hours to wait.

The lower 48 guide covers the storm levels those towns need, and the month hubs compare all 10 towns for each month.

• Pick a month with long civil nights at your destination from the matrix.
• Prefer weeks near an equinox if darkness allows, per SWPC.
• Center the trip on a new moon with the moon planner.
• Compare two destinations in the comparison tool.

Weather differs by place and season. The best month tool weighs civil night against NASA POWER's cloud average for your town. Build in spare nights so one cloudy night does not end the trip.