We now have the ability to “see” where lightning strikes anywhere on Earth. (here’s current lighting over the U.S.). Yes, we do get summer thunderstorms well up into the Arctic. Check out this map that shows where lightning occurred over a two-week period in late June-early July, 2016.
Note that the lightning occurred over interior land areas and not as much near the coasts, where cool, stable air made thunderstorms less likely. Juneau gets one thunderstorm every 1.9 years. Yakutat gets 3.1 thunderstorms per year. Eve In this area, lightning is most common in late summer and early fall, when the ocean is warmest. In the northernmost town of Barrow (Utqiagvik) has seen a couple of thunderstorms. From 2002 to 2015, the National Weather Service Offices in Anchorage and Fairbanks issued 51 severe thunderstorm warnings. 50,030 lightning strikes were observed from 1986-2012 for an area within 50 miles of Fairbanks. Half of those strikes occurred between June 16th and July 12th; a 27-day window.
Fairbanks averages 8 days per year with thunderstorms. The pic. above is from Eielson AFB at Fairbanks during a thunderstorm the evening of June 17 on base. Lightening storms are somewhat rare to base residents, however it is not uncommon for thunderstorms to occur in Alaska. (U.S. Air Force photo by Staff Sgt. Kevin Carter)