An evening of severe thunderstorms recently prompted this question. “Why do storms usually weaken just before moving into Fargo Moorhead? Is it the heat of the city?”
First of all, they don’t. But they may give this impression. Most thunderstorms pulse up and down and do not maintain their greatest strength for long. So unless you are just unlucky, it is likely that any storm will be stronger at some point before it hits you, not right when it hits you. Theoretically, a source of surface heat would tend to strengthen a storm instead of weakening it. But there is so much thermodynamic energy within a thunderstorm that a small surface temperature increase has little effect. The terrain differences in our region are not known to create any effects on thunderstorms.
