Tropical Storm Rina has strengthened a little more today as it moves northward into the cool waters of the Northern Atlantic. Rina has begun to acquire some subtropical characteristics, with a comma-shaped cloud pattern and little deep convection near the center. However, Rina maintains a warm core so it has not been declared a post-tropical cyclone yet. Regardless, Rina should transition into an extratropical cyclone late tonight or early Thursday as it loses all deep convection and becomes embedded in a frontal zone. Rina remains no threat to land and should dissipate before reaching the British Isles.
As of 10:00 a.m. EST Wednesday, Tropical Storm Rina was centered near 39.4°N 48.7°W, and was moving northward at about 21 mph. Maximum sustained winds were 50 knots (60 mph), with an estimated minimum pressure of 997 mb. Although a little more strengthening cannot be ruled out later today, the window for Rina to strengthen appears to be closing, and Rina is not expected to become a hurricane as it moves over even cooler waters late tonight and transitions into a post-tropical cyclone. Rina’s transition into a post-tropical cyclone could be the end of the 2017 Atlantic hurricane season, although with the way this season is going, I think we may see one more named storm before the season is over. The average final named storm for an Atlantic hurricane season dissipates in early November. If we do see another tropical cyclone form in the Atlantic before season’s end, it will most likely be in the central or eastern subtropical Atlantic or the southwestern Caribbean Sea.
I will be back with another post tomorrow, when Rina is likely to have transitioned into a post-tropical cyclone.