Special Tropical Update: September 27, 2011 (5:00p.m EDT)
Tropical Depression Ophelia
Data from a Hurricane Hunter Reconnaissance aircraft investigating the remnants of Ophelia this afternoon has found that the system has developed a surface circulation defined enough to meet the criteria of a tropical cyclone. Tropical Depression Ophelia has also become increasingly organized convectively this afternoon, with good upper-level outflow fanning out in all four quadrants. Additionally, upper-level winds are currently a favorable 5-10 knots and are only forecast to become more conducive for intensification as time progresses. This should result in gradual intensification of Ophelia throughout the next few days, with the cyclone likely becoming a hurricane in the 2-3 day time frame.
The cyclone currently appears to be moving towards the west-northwest under the influence of the southwestern periphery of the subtropical ridge. This direction in forward motion is unlikely to persist for too long, and the cyclone will probably begin to make a turn towards the northwest and north-northwest tonight into tomorrow. In about 3 days time, an amplified mid to upper-level trough is forecast to advect off of the eastern United States, and cause for the cyclone to recurve off towards the northeast. Interests in the northern Lesser Antilles, the U.S Virgin islands, and Puerto Rico should all monitor the progress of Ophelia.
Bermuda should also keep a weary eye on Ophelia, although I believe that the cyclone will pass east of them.
Figure 1. Infrared satellite image of Tropical Depression Ophelia valid 20:52 UTC, or 4:52p.m EDT.