Hi Brian,

Brian O'Halloran wrote:
Bz is now strongly negative - and I can spot a strong glow even though
we're deep in twilight (53N 7W)!

Bz was positive all day and into the evening when the skies were clear.
I think it was the arrival of clouds that made it flip. All we can see
now is the streetlight nebula.

Best Regards,
John.