But this year, as the Atlantic hurricane season approaches its peak, it is much quieter. And there is little sign we will witness a repeat of last year’s devastating onslaught of storms.
At the moment, there are no named storms and the National Hurricane Center is only tracking a minor disturbance over west Africa which has a slim chance to develop once it emerges over the Atlantic waters.
For several months now, the water temperature in the deep tropics between Africa and the Lesser Antilles has been cooler than average. So when disturbances exit the continent, they are immediately greeted with more stable air and less fuel than they would in a typical year.
Further west in the Atlantic, dry air has been in place for much of August, which is also inhospitable for storm development. The air has been unusually dry in the zones surrounded by maroon dashed lines in the map below. In fact, no storms have existed anywhere within these regions so far this season.
Looking ahead, another factor working against storm development is the growing possibility of a fledgling El Niño. By the end of hurricane season, there is roughly a 60 percent chance that El Niño will develop. All other things being equal, El Niño events act to suppress Atlantic hurricane activity as they tend to introduce wind shear which disrupts thunderstorm development.
While conditions have been less than favorable for Atlantic tropical storm development and may remain so, five named storms have still managed to form. Two of these storms became hurricanes (Beryl and Chris), but none became major hurricanes, rated Category 3 or higher.
Normally, by this date, there would be four named storms, one hurricane, and zero major hurricanes. But some of this year’s storms were rather short-lived. In terms of Accumulated Cyclone Energy – a measure of both the strength and longevity of storms – 2018 is at about 86 percent of average, or slightly below par, as of today.
Today is the first day all season that the tropical Atlantic has fallen below 100% of climatological ACE (Accumulated Cyclone Energy)! It is at 96% of average, and this time of year, will quickly slip further behind without active tropical cyclones. #tropics #HurricaneSeason pic.twitter.com/P3uQc8UtfK— Brian McNoldy (@BMcNoldy) August 21, 2018
Because late August into early September is normally such an active time for Atlantic storms, it’s easy to fall further behind the curve relative to average when there is little activity. And that’s what we’re seeing at the moment.
Overall hurricane activity is expected to remain lower than average in the coming weeks due to the combination of cool sea surface temperatures, dry air, and possible El Niño development.
But remember that even during a “slow” hurricane season, significant storms can still form and make landfall. If one of them happens to hit your area, it won’t feel like a slow season!
When the time comes, the next name on this year’s list is Florence, and we are still a couple weeks away from the average date of seventh named storm formation. The odds are we won’t have to wait that long, even in this quieter season compared with last year.
This is the time of year when we watch every disturbance closely because the vast majority of major hurricanes occur between late August and late September.