Hundreds of black-clad rockers were treated for heat exhaustion on the first day of the Wacken heavy metal festival in northern Germany on Thursday, the Hamburg-based Abendblatt newspaper reported.
And emergency services are repeating warnings to swimmers to be careful after nine people died in Bavaria just last weekend. Last year 383 people died in Germany's lakes and along the coast.
Hail the size of ping pong balls caused serious damage in the south west of the country earlier in the week - and as rising temperatures again increase the risk of storm, hail planes are on standby in Baden-Württemberg to fly into clouds. When up there, they spray a chemical which makes the ice chunks smaller, a spokesman from the Rems-Murr regional government said on Thursday.
Daytime temperatures of 24C in the north east and up to around 35C in the west during Thursday will not drop much as evening arrives, the German Weather Service (DWD) said, with top night time temperatures of between 21C and 14C.
On Friday, temperatures will rise to between 30C in the north east and 37C in the west. The absence of anything more than a light breeze will make the day feel particularly sticky.
By Saturday the north west will be hit with bad weather, with a strong chance of thunder and heavy, sporadic showers. This should ease by the afternoon though and the rest of the country should stay sunny.
Highs in the west and north west will stick between 24C and 30C while in the east and south it will be warmer – between 30C and 37C. As always, it will be a little cooler along the coastline.
Saturday night will be cloudy for those in the north west, but generally dry. Showers will head to give the east and south east a soaking, along with the occasional lightning bolt. Temperatures will stick at between 20C and 13C.
Sunday will be dry for most of the country. In some areas of the east and south it may be a little cloudy but everywhere else will once again see temperatures into the 30s. A gentle wind will offer only little relief from the heat.