A Multi-Faceted Examination of the Extratropical Transition of Tropical Cyclones
Steve Guimond, Jeffrey Hawkins, Joe Turk, Clay Blankenship and Patrick Harr
The Extratropical Transition (ET) of a tropical cyclone from a symmetric, warm-core structure into an asymmetric,
cold-core structure
occurs frequently in various subtropical ocean basins and can result in intense baroclinic storms affecting activities on land and at sea. One of the largest societal impacts and forecasting complexities with ET is the potential for precipitation enhancement that can lead to excessive accumulations. Therefore, a need exists for a detailed analysis in the area of quantitative precipitation forecasting (QPF) during ET events that will improve on the deficiencies of the present state.
Hurricane Karl (2004) and Typhoon Sonca (2005) were used to test some new approaches relating to the dissection of ET
precipitation that
include: (1) development of an algorithm to compute sounding parameters from AMSU retrievals of temperature and moisture (2) analysis of different multi-satellite blended
precipitation products utilizing calibrated IR observations and (3) mapping the structural phase of ET from a satellite perspective. In addition, a qualitative comparison
of the synoptic fields from the ECMWF and NOGAPS models with respect to each storm will be presented.
CLICK HERE TO DOWNLOAD FULL POWERPOINT SEMINAR PRESENTED TO THE NRL 19 JULY 2005
[Link to TRMM PR Animation of Typhoon Meari's (2004) Vertical Reflectivity Structure]
[Link to ECMWF Animation of Hurricane Karl's (2004) Potential Vorticity Structure]