Premise: The Battle of Mokra took place on October 10, 1445 near mountain Mokra (today in Makedonski Brod, Macedonia). It was an Ottoman retaliation to a message sent by Skanderbeg to Murad II. The Albanian forces under Skanderbeg defeated the Ottoman forces under Firuz Pasha. It was the second major Albanian victory over the Ottoman Empire.
Hypothesis: It was raining when the Battle of Mokra took place.