Doppler radar quick-looks from 4 PM P-3 flight, 25 August 2011

 

As Irene’s intensity remains steady as she moves up off the east coast of Florida north of the Bahama Islands (outlined in black south of the storm) NOAA P-3 missions continue to collect 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 Hurricane Irene sampled from the tail Doppler radar on the P-3 late on 25 August 2011. These images are at three altitudes, 1km, 5km, and 10km, using a composite of winds from all four legs oriented north-south, southeast-northwest, west-east, and northeast-southwest. Note the very broad area of strongest winds on the east-northeast side of the storm at all altitudes from 1 to 10 km, with a suggestion that the wind maximum is rotated upwind with increasing altitude from 1- to 5- km altitude. There is no noticeable tilt in the center of the circulation from 1- to 10-km altitude, however the wind field is very asymmetric suggesting that Irene is encountering vertical shear of the horizontal wind that is increasing from the west-southwest. Also visible in the analyses is a slight increase of scatterers from the previous analyses in the storm core at 10 km altitude suggesting that the deep convective activity has increased somewhat as the shear is increasing.

All the Irene radar composites at 0.5-km height resolution and gridded data are available at http://www.aoml.noaa.gov/hrd/Storm_pages/irene2011/.