Tuesday noon tropical update: Tropical Depression 13 forms

Tropical Depression Thirteen formed Tuesday morning in the Atlantic Ocean. The National Hurricane Center's forecast path shows the storm becoming a major hurricane late this week and approaching the northern end of the Caribbean Sea near the Leeward Islands by this weekend. At that point, it could be a Category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale, which would mean winds of 130-155 mph. The next name on the list is Lee.

Models are in fairly good agreement with significant strengthening of the system and with a path just north of the Caribbean. The main steering feature is a ridge of high pressure to the north around which the storm should curve. This path would take the system over record warm waters in that part of the Atlantic where sea surface temperatures are around 86°. Some northeast wind shear may limit its growth somewhat in the next couple of days, but later in the week the wind shear is expected to diminish. That would allow the storm to tap into those warm waters and strengthen quickly.

Longer-range models show it eventually swinging north and paralleling the East Coast of the US. Most models keep the center well east of the coastline, but it is too early to say if some impacts might reach the US.

It does not look like it will reach the Gulf of Mexico or pose a threat to Louisiana or Mississippi. We will watch it closely and will have more updates as the system takes shape this week.

Farther out, another strong tropical wave called Invest 96-L is moving out over the Atlantic from Africa. This one also has a high chance of development in the next seven days. It appears this one could stay on a more northerly route which may keep it out at sea. The next names after Lee are Margot, Nigel and Ophelia.