While not all parts of the state have seen thunderstorms over the past few hot and steamy days, storms have been frequent each day and have continued overnight and into this morning. The featured chart presents the frequency of having the automated weather station at the Des Moines Airport report thunder. Frequencies are binned by week of the year and hour of the day. The middle of June is the approximate peak in frequency along with the 3-4 AM early morning hours, so the ongoing storms this morning fit this plot well. It is interesting to see the minimum during the noon hour, which some may think as counter-intuitive as that is the approximate hour of peak heating (quasi solar noon). Storms tend to develop after the accumulated effect of the day's worth of heating and associated erosion of an elevated layer of warm air. For Iowa, the overnight maximum is related to the rotation of the "low level jet" with peak transport of unstable low level air into the state during the early morning hours.

Voting:
Good = 14
Bad = 0

Tags:   thunder