Thunder book

In the Annals from 1605, the Dubrovnik writer Jakov Lukarević says that Serbian kings Stefan Nemanja and Dušan "persecuted witches", whom he calls "evil women from Mount Hemo", and burned their book of magic, which was in Slavic tongue called Grominjak (Thunder book)...

That book probably had spells and rituals for affecting meteorological phenomena. St. Sava, in the "Zakonopravilo", condemns the magical summoning of hail, although he himself summons hail, in the story about the Hungarian king.

St Sava from Serbian folktales basically replaced Dabog, the old Serbian supreme god and took all his magical powers, including weather control...I talk about Dabog as both sun and rain god in two article "The last megalithic ritual in Europe" and "Weather stones" about the use of "weather stones" by Slavs to manipulate weather. Like here, where women raise Dabog's stone during drought to get cool and wet weather...

Another interesting bit here is that it is women who were always associated with rain (hail) storm rituals. 

Did you know that the sudden climate change which resulted in the medieval mini ice age was blamed on the weather controlling witches and was the excuse for the subsequent witch-hunt. I talked about this in my article "De Lamiis et Pythonicis Mulieribus" about the 1489 book "De Lamiis et Pythonicis Mulieribus" by Ulrich Molitor which talks about weather altering magic (witchcraft) performed by women...

This is an illustration from the book depicting "two witches conjuring up a destructive (hail) storm"...

In South Slavic folklore, cold, wet weather is "feminine"...Yin...

Which is why, in South Slavic folklore, it is a female dragon, ala, that brings hailstorms and unseasonably cold, wet weather during summer months, which destroys crops...I talked about this in my article "Pozoj"...

While male dragon, zmaj, brings hot, dry weather which brings drought, which destroys crops...Yang...I talked about this in my articles "Scaring off the dragon" and "Letnitsa treasure"...