June 30, 2021: This was not in the forecast. A low-amplitude interplanetary shock wave (data) hit Earth’s magnetic field during the early hours of June 30th, sparking mid-summer auroras over Canada:
Catalin Tapardel photographed the display from the Municipal District of Opportunity (#17) in Alberta. “I caught the auroras hovering just above an expanse of noctilucent clouds,” says Tapardel.
We don’t know where this shock wave came from. It might be the early arrival of the June 27th CME, originally expected July 1st, or perhaps a different stealthy CME that “flew under the radar” when it left the sun. If it’s the latter, another jolt could occur in the next 24 hours.
Update: Philip Granrud also saw the auroras from Kalispell, Montana. “…and a patch of noctilucent clouds, too!” he says. “It was a beautiful night in Montana.”