Northern Lights Put on a Show for Nine Border States Last Night

A Quiet Celestial Display Along the Northern Tier

Residents along the U.S.-Canadian border got a rare late-summer reason to step outside and look up. On Sunday night, August 31, the aurora borealis had a chance to shimmer over nine northern states, offering a modest but welcome celestial display as summer drew toward its close.

NOAA forecast a Kp index of four out of nine on Sunday night, meaning the aurora could appear brighter with more "motion and formations" in some places. While that's not the dramatic, sky-filling spectacle that major geomagnetic storms can produce, a Kp-4 reading is enough to push the northern lights visibly southward from their usual polar home — and that's all many skywatchers need.

Which States Were in the Viewing Zone

The aurora had a "low" likelihood of visibility for several states along the U.S.-Canadian border, according to NOAA's forecast map. These include northern Washington, Idaho, Montana, North Dakota, South Dakota, Minnesota, Wisconsin, and Michigan's Upper Peninsula. That's a broad swath of the northern tier, stretching from the Pacific Northwest all the way to the Great Lakes.

The lights also had a high likelihood of visibility from most of Alaska. However, the sun sets very late in Alaska during the summer months, meaning the night sky might not get dark enough for the aurora to become visible. It's one of the quirks of chasing auroras in late summer — even when solar activity cooperates, daylight doesn't always.

Forecasters at NOAA were not expecting any space weather events that could impact the aurora on Sunday night, according to the agency's most recent three-day forecast. However, the agency did issue an alert for the higher expected Kp index on Sunday afternoon. In other words, no solar storm was driving the show — just a natural uptick in geomagnetic activity that nudged the auroral oval a little further south than usual.

What Makes the Aurora Visible — and How to Catch It

The aurora borealis is a natural light display generated when charged solar particles travel across space and collide with Earth's magnetic field and atmospheric gases. Earth's magnetic field acts as a shield, funneling these high-energy solar particles toward the polar regions. When activity picks up, that funnel widens, and the glowing curtains of light drift toward lower latitudes.

Viewers should position themselves on an ideal vantage point with a good view of the sky facing north, ideally as far away as possible from cities or other sources of bright lights. The aurora is most active in the hours just before and after midnight, according to NOAA, so viewers should try to search for the aurora between 10 p.m. and 2 a.m. Dark, rural landscapes — open fields, lakeshores, elevated hillsides — give the best results.

For those who tried to photograph the display, modern smartphones are surprisingly capable. Photographers should remember to bring a tripod and remote timer when trying to capture images of the lights, as all cameras need to be held still for long periods of time to capture the aurora in the dark night sky. Smartphone users should also remember to turn off their flash settings, turn on night mode, and shoot using RAW image format if possible.

Looking Ahead: Aurora Season Is Far From Over

Sunday's display was relatively low-key, but the broader aurora season remains active. Just days earlier, a potent stream of solar wind and a coronal mass ejection struck Earth's magnetic field, with space weather forecasters predicting a G2-class geomagnetic storm that potentially brought the aurora into view from northern-tier states near the Canadian border. That event on August 28–29 was considerably more dramatic, underscoring how quickly conditions can change.

During periods of heightened solar emissions, the auroral oval expands, shifting the boundary of the visible lights further south. While major geomagnetic storms can push this boundary deep into the continental United States, even moderate increases in space weather activity can make the lights visible along the northern border. With solar activity still elevated in the current cycle, residents of northern states would be wise to keep an eye on NOAA's real-time forecasts — the next spectacular display could arrive with very little warning.