Can the Atlantic Extend its Dry Spell Another Week?

Invest 97L sputtering in the eastern Atlantic

For the first time since early July, the Atlantic this week showed signs of springing back to life, as a healthy disturbance rolling off Africa on Sunday quickly garnered modest development odds from hurricane forecasters, even before splashdown in the eastern Atlantic.

Early guidance from weather prediction models painted a mostly ripe environment ahead for the tropical sapling to slowly develop through about mid-week. Fast forward to today, and the system – designated Invest 97L by the National Hurricane Center on Monday – hasn’t done much more than spit and sputter westward, backfiring a trail of disjointed thunderstorms through the deep tropical Atlantic. With conditions looking less primed headed into the weekend, NHC is ratcheting down 97L’s formation potential, and the Atlantic may extend its period of hibernation – since Tropical Storm Colin on July 3rd – yet another week.

So far, the Atlantic has recorded three named storms – Alex, Bonnie, and Colin – about on schedule for early August. However, each of these storms was weak and short-lived, so overall tropical activity as measured by Accumulated Cyclone Energy or ACE, a seasonal scorecard based on storm strength and longevity, is well below average for the year. Though a full 90 percent of the Atlantic’s tropical activity comes after August 10th – an important consideration when looking ahead – the ACE so far is the lowest measured through August 10th since 2009. Even so, years like 2019, 1999, and 1998 recorded similarly low tropical activity early on, but ended the year above average, in some cases flipping the switch to hyperactive hurricane seasons.

In previous newsletters, we’ve discussed not reading too much into early season activity, as past performance is not necessarily an indicator of future performance, particularly before mid-August. With bullish predictions of a very active hurricane season in 2022, getting through the first ten days of August with such little activity and no hurricanes certainly feels unusual. But on the scorecard of a typical hurricane season, activity before about the last week of August doesn’t usually count for all that much.

The Atlantic’s on the clock, but with the brief window of opportunity quickly closing for Invest 97L, it looks like we may skate through another week without any organized tropical activity. Any week in August without a storm is a good week, so let’s hope the dry spell spills into overtime for the week ahead.