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As Tropical Storm Isaac passed into the southeastern Gulf of Mexico west of Florida (outlined in black line in top right of image) NOAA P-3 missions collected airborne Doppler radar data to use in initializing and evaluating model guidance. Included here you see images of the horizontal winds within the inner core of Tropical Storm Isaac sampled from the tail Doppler radar on the P-3 early on 27 August 2012. These images are at three altitudes, 1 km, 3 km, and 6 km, using a composite of winds from four legs oriented north-south, east-west, southwest-northeast, and northwest-southeast. Also plotted on the 1-km altitude analysis are the locations of dropsondes deployed (plotted using standard station symbols). Isaac’s circulation is much more organized than in the previous mission, with a clear circulation center at all altitudes shown, but still very asymmetric with the stronger winds north and east of the circulation center. The circulation center is only slightly tilted from south to north with increasing altitude from 1-km altitude to 6-km, much less so than the precious mission. The observed tilt with increasing altitude suggests that the southerly shear Isaac is embedded in is much weaker than in the previous mission. Above 6 km the circulation center tilted 5-10 km to the north and almost vanished above 9-km altitude, suggesting the storm has a way to go is gaining strength.

All the Isaac radar composites at 0.5-km height resolution are available at http://www.aoml.noaa.gov/hrd/Storm_pages/isaac2012/radar.html.