Aurora forecast strong across Alaska early this week

The aurora borealis will be out in force across much of Alaska Tuesday evening -- although meteorologists say cloudy skies over much of the state may block a good view.

A Monday aurora forecast page on the University of Alaska Fairbanks Geophysical Institute projected aurora intensity as a 7 on a scale from 0 to 9.

"Auroral activity will be high," officials with the institute wrote. "Weather permitting, highly active auroral displays will be visible overhead from Barrow to King Salmon, and low on the horizon from most of the Aleutians."

Donald Hampton, a member of the geophysical institute's staff, said the solar winds that generate aurora activity are ebbing from the peak of an 11-year cycle but still remain high across northern latitudes. The aurora may be visible well into the northern tier of Lower 48 states.

"The sunspot period actually gets quite jumbled up," Hampton said. "And that's when you get this magnetic field that's pointed straight out into space, and that's when you get this high-speed solar wind."

In addition to the favorable sunspot conditions, Hampton said, part of the aurora activity could be chalked up to the remnants of previous aurora activity.

"We had some really good storms in early October -- that high-speed stream's going to sweep past us in the next day or so," Hampton said.

The intense aurora has the potential to cause limited disruption to satellite-based signals, such as those from global positioning satellites.

"It tends to affect lower-frequency radio waves, so ham radio operators will definitely see an issue," Hampton said. "GPS can be affected a little bit, but our receivers usually do a good job."

Despite the optimistic outlook for solar activity, Anchorage-based National Weather Service forecaster Joe Wegman had a more down-to-earth take on seeing the aurora through Southcentral Alaska's skies on Tuesday.

"We're in a stormy weather pattern right now -- it's not a favorable pattern for having a lot of clear skies to see the aurora," Wegman said. "A storm system just went through last night, and there's another one right on its heels; we've got several chances of precipitation still in the forecast."

Wegman said the forecast was personally disappointing as well, due to his own interest in seeing the aurora.

"I've been discussing that with my colleagues, because it's one of those times when I'd like the skies to be clear," Wegman said. "Unfortunately, it's just not in the cards right now."

Most of UAF's instruments, including cameras, radar systems and magnetometers, are ground-based -- but Hampton said that even with poor weather, researchers can compare their data with that collected by teams across the U.S. and from orbiting satellites.

Anchorage residents' best chance of seeing the aurora, according to Wegman, will occur Wednesday night as skies become partly cloudy. By then, the geophysical institute expects aurora displays to become "moderate," continuing through Friday until they weaken further over the weekend.