The tropics are beginning to boil. After a quiet August so far, forecasters are eyeing a tropical wave that came off the African coast Sunday.

Another one to watch is expected to come off the coast Friday, said Jeff Masters of Weather Underground. That one has a better chance of “re-curving,” or turning toward possible landfall along the East Coast, he said.

There are signs that the shear winds and Saharan dust, which have been knocking down hurricane-forming storms in the eastern Atlantic, are easing.

Comparing satellite imagery and computer models from a month ago to today, “We’re seeing a little more tropical activity ramping up,” said meteorologist Emily Timte with the National Weather Service, Charleston.

It’s now the height of the Cape Verde period, the heart of the hurricane year, when tropical cyclones tend to form off the African coast and turn into powerful hurricanes as they cross the Atlantic. Those storms pose the greatest threat to the Southeast.

The season has produced five named storms, which is ahead of average, and it’s still expected to be a busier-than-average season.

The chance of a tropical cyclone forming doubles this week, according to National Hurricane Center charting of storms during the past 100 years.

The Cape Verde period tends to run from mid-August into October, but this year an early Cape Verde system, Tropical Storm Dorian, formed in July.

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