The tropics continue to be quite active which is not too surprising given that the month of September is the climatological peak for the Atlantic basin tropical season. There are now three separate systems to monitor including Tropical Storm Leslie, Tropical Storm Michael and what can be called the “Son of Isaac”.
Of all three of these systems, Tropical Storm Leslie is of most concern as it will become a large Atlantic hurricane. In fact, it is now very near hurricane strength with sustained winds at 70 mph and some intensification should continue over the next few days. Leslie continues to move at a snail’s pace (North at 2 mph) and will continue to do so for the next few days as it is encountering a blocking high pressure ridge to the north and east of the storm center. By the weekend, a strong trough of low pressure will move out of southern Canada towards the US east coast and it should act to accelerate Leslie to the north. There still are a few questions that remain regarding the exact strength and location of the deep trough that will drop out of Canada this weekend and heads towards the US east coast; consequently, there are still some concerns that Leslie takes a slightly more westward track than currently projected by the models (ie closer to the US east coast). We’ll continue to monitor it – right now odds favor an ultimate movement of Leslie towards the Atlantic Canadian provinces of Nova Scotia or Newfoundland early next week after perhaps hitting Bermuda quite hard this weekend. Nonetheless, Leslie will cause rough surf up and down the US east coast right through the weekend and this projected track can still shift to the west somewhat.
Tropical Storm Michael is way out there in the Atlantic, well to the east of Leslie, and it appears to be headed in a generally northward direction over the next few days which will keep it far from any land masses for the foreseeable future.
Finally, a very slow-moving disturbance near the north-central Gulf of Mexico is actually associated with the “tail-end” remnants of Isaac. It is somewhat difficult to decipher, but it appears as if Isaac split into two parts over the past couple of days with one feature now over the eastern Great Lakes and the other near the Gulf of Mexico. This Gulf system that can be referred to as the “Son of Isaac” will generate more heavy rainfall over the next couple of days from Louisiana to the Florida Panhandle. It is a little too early to tell if the core of this system will actually intensify over the Gulf of Mexico waters into something strong enough to achieve “tropical storm” status (if so, it would not get the name Isaac).