The National Hurricane Center raised its Atlantic hurricane forecast on Monday, increasing the chance that a trough of low pressure in the central subtropical Atlantic will develop into a tropical depression or storm to 40% over the next seven days. The system was still about 1,000 miles east-southeast of Bermuda at 2 p.m. EDT.
The outlook gives the system a much higher chance than the 20% forecast on Sunday. It also points to late this week as the earliest window for a tropical depression, which would make this the season’s next named system if development continues.
The NHC outlook
The National Hurricane Center said the trough remained disorganized, with showers and thunderstorms not yet organized around a center. That matters for the forecast itself: the system has a development path, but it has not yet made the structural change needed to become a tropical depression.
Forecasters said environmental conditions over the system are expected to become more conducive for development by the middle of this week, while the system moves slowly west-northwest over the subtropical Atlantic. That combination gives the disturbance more time over open water and more room to organize before any stronger system could emerge.
Arthur, Bertha, Cristobal, Dolly and Edouard have formed this hurricane season, but no actual hurricane has formed so far. The season began June 1 and runs through Nov. 30, with the height of hurricane season running from mid-August through mid-October.
Edouard and NOAA
The lull since Edouard adds weight to the new outlook. Edouard made landfall in Louisiana, and the National Hurricane Center’s last advisory on it came on Sept. 3 as it moved inland over Texas.
The National Oceanic and Atmospheric Administration last month said it expects between seven and 13 named storms this year, with two to six hurricanes and at most two major hurricanes. It also said an average year would see 14 named storms and seven hurricanes, with three of those reaching Category 3 strength or higher.
For now, the practical next step is simple: the system needs to organize further before any stronger classification comes into view. The NHC’s update puts the focus on late this week, when forecasters said a tropical depression could form if the disturbance keeps consolidating.
