Kaiserwetter

Etymology
From 🇰🇲. Originally referred to the notion that the weather was usually sunny on the birthday of Austrian Emperor (reigned 1848–1916). In the German Empire, it also referred to the belief that there was sunny weather when Emperor (reigned 1888–1918) appeared at open-air events.

Noun

 * 1)  clear, sunny weather, usually with pleasant temperatures, and especially when there is some event