First chance I've had to observe the Sun in many days!
There is a correlation between Solar Minimum and an increased occurence of noctilucent clouds.
During Solar Minimum there are more coronal "holes" that allow solar particles (solar wind) to escape. This can actually trigger geomagnetic storms. Which may enhance the noctilucent effect. I think ?.

Canon IXUS185, Coronado P. S. T.
Eyepiece projection at 26X