As Tropical Storm Tomas continues to reorganize south of Hispaniola and Jamaica (seen in upper left and right of image outlined in black lines) a NOAA P-3 mission collected airborne Doppler radar data to use in improving our understanding of tropical cyclone intensification, as well as for initializing and evaluating model guidance. Included here you will see images of the horizontal winds within about 150 km of the center of the disturbance sampled from the tail Doppler radar on the P-3 late on 4 November 2010. These images are at three altitudes, 1 km, 3 km, and 6 km, using a composite of winds from three legs oriented east-west, southwest-northeast, and north-south. Wind, temperature and relative humidity from GPS dropsondes dropped from the P-3 are also visible at 1 and 3 km altitudes. The changes observed in the circulation between the next two missions suggests that the storm is getting better organized, which was also suggested by the minimum central pressure falling from 997 hPa in the first flight to 989 hPa in the second, roughly 12 h later. Compared to the previous flight the circulation appears to be more aligned in the vertical at all altitudes. As in the earlier flight the circulation from 1-3 km altitude appears to have the stronger winds closer to the low-level center, whereas at 6 km altitude the circulation appears more asymmetric about the center with the stronger winds a little closer to the circulation center. The outer circulation still appears to be relatively asymmetric suggesting that the storm is still feeling southwesterly vertical wind shear of the horizontal wind.
Published on: November 6, 2010