Thunderstorms and lightning strikes are most likely in spring and summer storms.
The only law against magic made by Constantine in 321 AD exempts magical “steps taken in country districts, that there may be no apprehension of (heavy) rain when the grapes are ripe, or that they may not be dashed to pieces by the force of hailstorms.” (You can read more in Witchcraft and Magic in Europe: Ancient Greece and Rome.)
There are references to weather magic as early as ancient Greece, as in this quote by Empedocles:
And you’ll stop the force of the tireless winds that chase over the earth
And destroy the fields with their gusts and blasts;
But then again, if you so wish, you’ll stir up winds as requital.
Out of a black rainstorm you’ll create a timely drought
For men, and out of a summer drought you’ll create
Tree-nurturing floods that will stream through the ether
And you will fetch back from Hades the life-force of a man who has died.
(see more in Ancient Philosophy, Mystery, and Magic: Empedocles and Pythagorean Tradition, with thanks to http://www.otherworld-apothecary.com)
In the Jewish practice, a blessing “…He who does acts of creation” is to be recited, upon sighting lightning. The Talmud refers to the Hebrew word for the sky, (“Shamaim“) – as built from fire and water (“Esh Umaim“), since the sky is the source of the inexplicable mixture of “fire” and water that come together, during rainstorms. This is mentioned in various prayers and discussed in writings of Kabbalah.
The Norse rune known as “Thorn” is also associated with lightning for a variety of reasons. It is the rune of cutting, sharpness, and pain, as well as brute strength, the destructive power of chaos and ruin. It also stands in for death and regeneration, transformation and the breaking down barriers. It can be used to bring on the energies of the berserker and energies this wild should only be used in war or attack. It can be used in magic to raise and guide thunderstorms and direct lightning. In many German fairy tales such as “Sleeping Beauty” the prick of a thorn, pin or spindle casts a spell upon the victim. The bloodstone has been used with this rune in the raising of thunderstorms.