The above image was just taken from the radar site at San Juan, Puerto Rico. As you can see, Tropical Storm Irene is becoming better defined, with an eye-like feature clearly taking shape around the center. As of the 8pm EDT National Hurricane Center advisory, the center was located 90 miles East/Southeast of San Juan, and moving West/Northwest at 15 mph.
The wind velocity (wind speed and direction) mode of the radar indicates sustained winds of 64 mph about 5,000 feet above the surface, on the Northern side of the center (white circled area with text notation on the image below):
About a half an hour ago, an Air Force Hurricane Hunter aircraft measured a surface wind of 60 mph near the same location. Meanwhile, the barometric pressure at the airport in St. Croix has fallen to 29.38 inches of mercury - another sign of an intensifying system.
Based on the present track of the system, as well as the location of the strongest surface winds in relation to the center, at least Tropical Storm force winds can be expected across Puerto Rico this evening into tonight, and I would not be surprised if Hurricane or near Hurricane force winds were to take place later tonight, particularly across the Northern one-half of the island.
For details on the forecast track of Irene beyond Puerto Rico, including the potential for a significant impact across most of the U.S. Eastern seaboard, please see my earlier post here.
If you enjoy reading 'The Original Weather Blog', please be sure to "like" our facebook page!