Old and Middle English thunder-books warn that thunder heard in Cancer means “there shall be great hunger and butterflies shall destroy fruitsâ€**
Unlucky days for June, according to the old Sarum Missal, are the 10th and 15th, so watch out! To quote F.C. Husenbeth’s fanciful translation:
The tenth a palid visage shows,
No faith nor truce the fifteenth knows.***
from GotMedieval.com’s Whan that Juine