Lots of factors in play but Tropical Storm Sara is expected to form this week and could become a major hurricane threatening the US next week.

A somewhat rare November storm system is gathering steam in the Caribbean Sea. Tropical Storm Sara will eventually make a turn to the east and Florida.

The National Hurricane Center began advisories Wednesday on a system it forecasts to become the season’s next tropical depression or storm. Long-range forecast models predict it will intensify into a hurricane and threaten Florida by the middle of next week.