Storm system off U.S. East Coast has 40 per cent chance of tropical development

A storm-force low-pressure system off the coast of North Carolina could gradually develop subtropical or tropical characteristics over the next several days, according to the U.S. National Hurricane Center.

The system, designated AL93, remains attached to an occluded frontal boundary a few hundred miles offshore. It is expected to move slowly north-northeastward over the Gulf Stream, potentially developing more organized thunderstorm activity as it gradually loses its frontal features.

The system has a 30 per cent chance of developing into a subtropical or tropical system within 48 hours and a 40 per cent chance over the next seven days.

By the end of the week, the low is expected to accelerate northeastward away from the eastern United States, where environmental conditions are forecast to become less favourable for further development.

Regardless of whether the system becomes subtropical or tropical, high winds, coastal flooding and dangerous surf are expected along portions of the U.S. East Coast over the next few days.