TROPICAL STAY QUIET INTO NEXT WEEK AT A PATTERN CHANGE BRINGS MORE DUST
A strong high-pressure system is establishing itself over the Atlantic Ocean – the so-called Bermuda High. The flow around this high has two main effects on the tropics.
First, the uninterrupted air flow from Africa all the way to Florida and the Gulf of Mexico is a corridor for more Saharan Dust to push across the Atlantic. As we have seen, the plume of dust dries out a layer of the atmosphere above the ocean’s surface, which makes it difficult for tropical systems to develop.
But also, a strong high-pressure system like this one tends to push the disturbances that move off Africa – low-pressure systems – farther south where it is harder for them to develop. And if they do develop, they run into South America.
A key factor in getting a tropical system rotating is the spin induced by the rotation of the earth. That factor is weaker the closer to the equator you get. So systems farther south have a harder time getting going.
So even though robust disturbances are moving off Africa, there are no signs that the atmosphere over the Atlantic will allow them to organize.
Embedded in the river of air across the ocean are mini-disturbances, however. They come by with moisture and sometimes an increase in the ocean breeze, increasing the chances of rain over the Florida peninsula.
Two back-to-back mini disturbances will impact South Florida over the next several days bringing in more clouds and thunderstorms. The stronger ocean breeze will also keep the temperatures close to the normal range, breaking the extended heat wave that has been dominating this summer.
When the mini disturbances move into the Gulf of Mexico, conditions are sometimes a bit more favorable for development, so we’ll keep an eye on that. But there is no sign of anything getting organized anytime soon.
The bottom line is, no tropical develop is expected well into next week, at least.