The Midsummer Tropical Nap Continues Though There Are Hints It Might Wake Up

There are no signs of any tropical development well into August, but there are early signs that the eastern Atlantic might become more hospitable to disturbances moving off Africa around the middle of the month.

For now, the El Niño-driven hostile upper-level winds and Saharan dust are dominating the atmosphere over the Caribbean and the tropical Atlantic. In addition, the ocean water remains quite cool, though it's warming into a range that could support tropical development.

On average, the mechanism over Africa that produces the large Saharan dust plumes begins to wind down in August, or at least the dust outbreaks are less frequent. But sometimes they continue into early September. We'll see what happens this year.

The extremely hostile upper-level winds are likely to continue over the Caribbean as the El Niño heads for "super" status. That means if a disturbance moving off Africa were to develop, it would likely have to track north of the islands where the atmosphere is somewhat more conducive to development, and the ocean water is quite warm.

Tropical disturbances have been departing Africa all summer, but the Atlantic has been so inhospitable that they have remained weak until they reached the Pacific, where a number have developed into hurricanes.

The long-range computer forecast models are finally indicating the possibility a strong enough disturbance will move off Africa around the middle of next month that it can survive over the tropical Atlantic. At this long forecast horizon, the odds are still low, but it's interesting to see the possibility show up in both the traditional and AI models.

It would be more unusual if we didn't see some African disturbances in the models over the Atlantic in mid-August, so there's really nothing to think about right now.

Enjoy the nap.