by Ted Keller
Ring of Fire
6:17 am in Did You Know? by Ted Keller
This is a phrase which I’ve actually heard more in connection with the volcanic activity which lines the Pacific Ocean basin but it has also been used to describe the ring of thunderstorms which is sometimes observed in the central United States during the summer months.
Thunderstorms should love summer in the U.S. because the air is hot and humid making it unstable. But as the jet stream retreats northward during this season, it is replaced aloft by an area of high pressure. This feature promotes sinking air which has the effect of “snuffing out” storms which are by there very nature creatures of strongly rising air.
Other features which can help lift the air such as fronts or strong jet streams aloft are circulating around this high, turning in a clockwise direction. This activity is mostly observed on the northern edge of the high.
A ring is a circle of course. To complete the effect, storms are often active on the western edge of the high near the Rocky Mountains where a weak jet stream and orographic lifting are in play. Also, weak easterly waves, sea breeze circulations and a deeper humidity supply found near the Gulf of Mexico round out the southern edge of the ring.
