Sean Stumbles while Invest 94L Plods West

Tropical Storm Sean expected to remain weak and over water but 94L may move toward the islands for late next week

Historically by this point in the hurricane season, roughly 85% of named storms have already formed in the Atlantic. This means that in a typical year, we would still expect 2 more named storms before the end of November, with one of those named storms strengthening into a hurricane. So while the season isn’t over by any measure, it’s transitioning from a steady stream of storms to a trickle.

Today we’re tracking two systems in the eastern Atlantic, a less common locale for formation this late in the season. In October, only about 1 in 7 tropical systems forms east of the islands in the deep tropics. In most Octobers getting one storm out here would be noteworthy, let alone two. The last time two tropical cyclones formed in the tropical Atlantic in October in the same season was back in 2001, when Iris and Jerry came together during October’s opening week.

Sean is still hanging on about 1000 miles west of Africa. The storm weakened Wednesday night to a Tropical Depression and continues to battle strong wind shear from the southwest. Wind shear should keep Sean from strengthening much if at all in the coming days, and NHC forecasts the system to unravel over the weekend as it stays over the open Atlantic.

Behind Sean, Invest 94L – a broad area of low pressure south of the Cabo Verde islands off Africa – will be slow to cook into the weekend. We’ll want to follow 94L into next week as it moves westward toward the islands. Some of our models show a more conducive environment for organization ahead, so gradual development can’t be ruled out. Any potential threat to the eastern Caribbean islands won’t come until late next week at the soonest so we’ll have plenty of time to monitor.

South Florida’s first real cold front of fall could signal a tapering off of tropical threats

We’ll be eyeing what looks to be the passage our first real fall cold front through South Florida by Sunday into Monday. Not only will this usher in some refreshingly dry and cooler weather, but it’ll kick us into dry season, a point in hurricane season we begin to see storm threats subside for South Florida. Tropical threats still happen even into November, so don’t toss out your hurricane supplies just yet. That said, making it to dry season without a South Florida hurricane is an important step to closing out hurricane season.