After space weather experts said earlier this week the northern lights might make a rare appearance in the Colorado sky, people across the state braved the cold and the wind overnight hoping to catch a glimpse of the light show.

But alas, the lights did not light up the sky, and experts say it is not likely they will show up tonight either.

Joe Kunches, a forecaster with the Space Weather Prediction Center in Boulder, said the solar storm was not powerful enough to produce lights strong enough to be clearly visible in Colorado -- or the entire North American continent for that matter.

"It just didn't pan out," Kunches said. "It was not the right stuff."

This photo of the aurora borealis was taken Thursday in Norway by Harald Albrigtsen. Despite forecasters saying the lights had a chance to make their way
This photo of the aurora borealis was taken Thursday in Norway by Harald Albrigtsen. Despite forecasters saying the lights had a chance to make their way as far south as Colorado, they did not appear in the U.S. (spaceweather.com)

Kunches said the disturbance created by the storm did arrive, but it was a lot weaker than forecasters had predicted.

"When we measured, it turned out to be really weak," Kunches said. "As a consequence, the disturbance was very minor and the auroras were not that bright."

The aurora borealis is caused when energetic electrons from solar storms interact with the thin gases in Earth's upper atmosphere. But Kunches said the brightness of an aurora is hard to predict beforehand because it is hard to gauge how strong the storm will be.

"There is a complicated key ingredient that dictates how strong the magnetic storm -- which dictates how bright and equator-ward the aurora will be -- that forecasters just don't know days ahead," Kunches said. "It's like in baseball. You can see where the pitch is coming from, but it's hard to see the spin on the ball. In this case it's not quite spin, but just an embedded feature of the plasma that comes from the sun."

Kunches also said most of the U.S. was cloudy Thursday night, so even if the lights had been stronger, it's not likely they would have been very visible.

"For better or for worse, the weather over North America was cloudy, so even if there would have been a big event, it would not have been visible from most places," he said.

Kunches said the only place he knew of where the northern lights were clearly visible was in Norway, where they are far more common.

"The good news is the lights were seen," he said. "The bad news is they weren't here."

And Kunches said there is even more bad news: The lights will not likely show up tonight either.

"I've been burned before, but I'm going to go out on a limb and say I don't think there will be any activity tonight," he said. "We think we're done with this one, and we've seen all we're going to see."

For those still willing to take a gamble, the forecast tonight calls for partly cloudy skies, but winds will be 16 mph to 21 mph. Experts say the best places to see the aurora borealis are away from city lights with a clear view of the northern horizon, including Wonderland Hill in north Boulder.

Kunches said the sun will be at the peak of its solar cycle for another few years, so there still remains a chance Colorado and parts of the lower 48 could see the lights return. But even during the peak, there are only about four times every year when that is even a possibility.

"Even at the height of the solar cycle, this is a rare event," he said. "It hasn't been a strong peak anyway, and we're making our way toward the solar minimum."

Those who want updates can also check the Space Weather Prediction Center for updates on the storm and www.aurorasaurus.org, a site designed to track confirmed aurora borealis sightings.

Contact Camera Staff Writer Mitchell Byars at 303-473-1329, byarsm@dailycamera.com or twitter.com/mitchellbyars.