Last week I wrote about how quiet it was across the tropics - not just in the Atlantic Basin but across the rest of the Northern Hemisphere as well. There hasn’t been any further development anywhere in the world since my last update, and I’m seeing signals that at least the Atlantic Basin may remain quiet over the coming weeks.
For much of the month of June, a weak upward motion pulse has dominated the western Caribbean Sea and the East Pacific. These pulses of upward-moving air travel around the globe, causing increasing thunderstorms and often a significant increase in tropical development for weeks at a time as they pass. But that wasn’t the case with the current upward pulse. Only a single named storm has developed in the East Pacific, and it appears we’ll make it through June without a named storm in the Atlantic Basin. But what can we expect over the coming weeks?
The graphic above is a two-week prediction of areas of rising and sinking air across the tropics. Note the huge area of sinking air from the Indian Ocean through the West Pacific. In India, they’re praying for rain as the monsoon is more than three weeks late. Only a couple of named storms have formed in the West Pacific this month in that sinking air region. Now look at the projections for the East Pacific and the Caribbean Sea/Tropical Atlantic. The period of increased thunderstorms across this region is forecast to come to an end in a few days, replaced by an ever-expanding area of sinking air and even fewer thunderstorms by mid July.
Such a large area of sinking air, should it materialize, would certainly inhibit tropical cyclone formation in the main development region of the Atlantic Basin in July. That’s not to say it’s a guarantee of no tropical storms or hurricanes in the entire Atlantic Basin for the next 2-4 weeks. The area north of 20N latitude, including much of the Gulf of Mexico, may not be affected, as well as the open Atlantic north of 20N latitude. So it’s not impossible for something to develop in the upcoming weeks, it just appears unlikely that development will occur.
I’ll continue to monitor this projection over the coming weeks and will report back on its development from time to time. Meanwhile, enjoy the tropical quiet while it lasts.
