Much of the upper US could be treated to some celestial theatrics.
The Space Weather Prediction Center (SWPC) at NOAA has some good news for skywatchers this weekend. The geomagnetic storm watch notice is calling for ample geomagnetic activity ... which means an increased chance of viewing the aurora borealis farther south than normal.
"Geomagnetic activity is expected to rise on September 27th due to an increasingly disturbed solar wind field associated with effects of a positive polarity coronal hole high speed stream," notes the SWPC. "Geomagnetic activity is expected to escalate further in reaction to the elevated solar wind speed and likely reach G2 storm levels on Saturday, the 28th."And a waxing moon is the icing on the cake, ensuring a darker sky for increased effect.
Geomagnetic storm watches are now in effect for 27-29 Sep due to CH HSS influences. A new and young waxing moon this weekend will make for dark skies where it is clear; so keep checking https://t.co/9n7phHb5ok for the latest information and forecasts regarding this activity. pic.twitter.com/S8YLRaxNIs— NOAA Space Weather (@NWSSWPC) September 26, 2019
The map above is a bit difficult to read (a larger version is here), but as Thrillist explains, "with a maximum Kp level of 6, you're looking at an area between the green and yellow lines during the G2 alert and as far south as the green line during a smaller G1 alert."
Beyond Canada and Alaska, for whom surely this is old hat by now, northern Idaho, northern Iowa, Maine, Michigan, Minnesota, Montana, New Hampshire, New York, North Dakota, South Dakota, Vermont, Washington, and Wisconsin will all get a chance to potentially view the aurora as well.
The SWPC notes the following:
• G1 (Minor) Storm Watch: Friday, September 27 UTC-day
• G2 (Moderate) Storm Watch: Saturday, September 28 UTC-day
• G1 (Minor) Storm Watch: Sunday, September 29 UTC-day
So here's the drill: Be sure you are away from light pollution (sorry, city slickers), wait until it gets dark, and look towards the northern horizon. They may come and go, so be patient. They will likely not look like the psychedelic light shows seen in Norway and other parts far north, but even baby northern lights are pretty thrilling.
For more information, visit the Space Weather Prediction Center.