Some states near and along the Canadian border may have an opportunity to view the northern lights on Wednesday night, which may be the last chance for stargazers this week, according to the National Oceanic and Atmospheric Administration.
A portion of the northern U.S. could have an opportunity to see the colorful phenomenon.
The NOAA forecast a Kp index of three on a scale of nine for Wednesday night, indicating there will be an increase in auroral activity that can be “quite pleasing to look at” for stargazers in the right areas.
Wednesday’s view line—marking a minimal chance of seeing the phenomenon—is expected to be pulled further south to more states as the Kp index is expected to increase above four, the NOAA said.
Auroral activity is expected to decrease over the next two days, with a Kp index of two and one expected for Thursday and Friday, respectively, according to NOAA’s three-day forecast.
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Most of Alaska and northern Canada will have a chance to see the northern lights, while parts of northeastern Washington, northern Idaho, northern Montana, North Dakota, northern Minnesota, northern Wisconsin and Upper Michigan have a lower likelihood. If the Kp index increases to four, similar forecasts push the view line into South Dakota, and areas in northern Maine may have an opportunity to view aurora borealis. (See view line below.)
Wednesday night's view line.
The northern lights are best seen between 10 p.m. and 2 a.m. local time while at a high vantage point away from light pollution, according to the NOAA.
If using a regular camera, National Geographic suggests using wide-angle lenses, an aperture or F-stop of four or less and a focus set to the farthest possible setting to capture the northern lights. If using a smartphone, it’s recommended to turn on night mode and disable flash.
Aurora borealis is the result of electrons from solar events—solar flares and coronal mass ejections—interacting with molecules and atoms of nitrogen in the Earth’s atmosphere. This activity causes these electrons to become “excited” before producing the colorful displays of the northern lights. More northern lights displays are expected through early 2026, after activity on the sun’s surface reached a “solar maximum” in October 2024. Activity on the sun’s surface is measured over 11-year periods, during which a “solar maximum” and “solar minimum” are achieved. The latest “solar maximum” resulted in a 500-year peak for auroral activity in 2024, as the strongest geomagnetic storm in the last two decades affected Earth in May, bringing the northern lights as far south as Texas and northern Florida.