Why Is September The Peak Of Hurricane Season?
Hurricane season in the Atlantic runs from June 1st to November 30th. It hits its peak in mid September which is later than may people think. This is for two reasons.
1) Shear is at its lowest during the month of September. Shear is the change of direction and speed with height of the wind. Typically this time of the temperature difference between the equator and north pole, while large, is smaller than in winter leading to less shear. This is important because shear kills hurricanes.
2) The water is at its warmest this time of year. The temperature needs to be 80° or warmer to fuel a hurricane. The northern hemisphere will continue to see more than 12 hours of daylight for another couple weeks. This solar radiation will continue to warm the water or at least keep it warm. Once we get less than 12 hours of sun, we will see a slow cool off. It takes water three times as much energy to heat up and it also takes about 3 times longer to cool off. This is why the season can run all the way to November 30th.