On July 5th, Dr Gary Lackmann from NC State University lead a webinar entitled “How are tropical cyclones represented in operational model initial conditions? And why does it matter?” The webinar was attended live by more than 15 different offices with the recorded presentation and a PDF of the slides available at the links below.
The presentation was inspired by research activities associated with CSTAR Grant #NA10NWS4680007 that in part aimed to better understand tropical cyclone (TC) initial conditions and investigated the use of the GFDL bogus vortex to improve local modeling of TCs. In addition to sharing these results, the presentation begins with some background and motivation that notes some of the challenges of TC prediction and initialization. The presentation provides some background on data assimilation (DA) and discusses tropical cyclone DA. The Hybrid DA now used in the GFS is discussed a great deal since it is new and hopefully will provide some notable improvements and since the GFS is cycled into the NAM & RAP and used in the HWRF & GFDL. A short discussion of the operational models and tropical cyclone initial conditions is provided for the GFS, HWRF, GFDL, RAP, and NAM.