JACKSON, Wyo. — Why not close out the year with yet another appearance by the aurora borealis?
The National Oceanic and Atmospheric Administration’s Space Weather Prediction Center (SWPC) has announced that it is anticipating increased geomagnetic activity over the next few days with the arrival of two coronal mass ejections headed in the direction of Earth. The SWPC has issued a strong geomagnetic storm watch for the wee hours of Tuesday, Dec. 31, with the potential for more activity before and after that date.
SWPC’s aurora forecast projects a view line that appears to be right on the cusp for viewers in Jackson Hole. Viewers in Yellowstone National Park might have a better shot at seeing the lights.
NOAA is predicting a Kp index of six to be reached overnight. Derived from the German “Planetarische Kennziffer,” or planetary index, the Kp scale runs from zero to nine.
As explained by Wyoming Stargazing, the Kp index “measures the disruption of the horizontal distribution of the geomagnetic activity…A value of zero means that even Fairbanks, Alaska, would have difficulty in seeing the northern lights. One to three is most common, and that’s what is frequently seen in those northern latitudes of northern Canada and Alaska. A four would push them down into southern Canada, while a five, in the right conditions, might just barely be visible on the northern horizon here in Jackson Hole. To see them well, we typically need at least a six.”
2024 has been a major year for aurora-watching in Wyoming. In May, the Kp index reached nine, resulting in a powerful, multi-colored aurora. In October, the lights appeared again in a less powerful storm.
The National Weather Service’s Riverton Office forecasts cloudy skies in northwestern Wyoming on Monday night, which could hamper aurora viewing opportunities. But Monday night’s new moon could be helpful for visibility if the clouds end up parting. Even if viewing conditions are perfect, it’s difficult to predict the aurora with much certainty.
To try to view the aurora, head to a very dark place away from light pollution and allow the eyes to adjust, which could take 15 to 30 minutes. Turn to the north-northeast and look at the horizon.
Keep an eye on the Space Weather Prediction Center to see how the forecast evolves.
