Irene does have a low level circulation!
"As of 11pm this evening, Irene is back to tropical storm status, with winds of 40mph. Earlier this evening, some of the data (namely QuikSCAT) were inconclusive as to whether or not there was a low-level center. However, the storm was right on the edge of the pass and, as we've seen, the technology isn't always perfect. It does a good job, particularly with wind speeds, but with small systems and circulations, it does have trouble from time to time. Nevertheless, visible imagery was absolutely conclusive -- there was and is a low-level center with the storm, with good banding features to the south of the center of circulation. Microwave imagery (SSM/I pass this evening, available from the NRL website) confirmed these banding features, both at the low and mid levels, suggesting a system with the building blocks firmly in place. The deepest convection is building closer to where the center is located on the NW side of the overall cloud pattern, shear values are down to around 10kt, and waters are progressively warmer to the west."
http://flhurricane.com/blog.php?met=Clark