Research Summaries

Back Improvement of Short-Term Prediction of Tropical Cyclogenesis in the 0-5 Day Lead Time by Incorporating and Evaluating the HWRF-Genesis Model Within the Marsupial Framework and New Lagrangian Flow Techniques

Fiscal Year 2015
Division Graduate School of Engineering & Applied Science
Department Meteorology
Investigator(s) Montgomery, Michael T.
Sponsor National Oceanic & Atmospheric Administration (Other-Fed)
Summary The investigation proposed herein is aimed at improving short-term prediction of tropical cyclogenesis in the Atlantic and East Pacific sectors at 0-120 hours lead time (0-5 days), specifically by guidance from HRD’s HWRF-Genesis model. This work best meets Program Priority #5 by providing enhanced diagnostics for the HWRF-Genesis model on the location and timing of cyclogenesis. The methodology is derived from the suite of “pouch products” accessible publicly at the Naval Postgraduate School (NPS) Montgomery Research Group (MRG) website. The scientific basis of the new methodology is given in Dunkerton et al. (2009, ACP) and Montgomery et al. (2012, BAMS).
Regions of quasi-closed recirculation are identified in the lower troposphere (700-925 hPa) using available 5-day forecasts from HWRF-Genesis. These regions are tracked for as long as they exist in the 5-day forecast interval. Metrics of vorticity (?), Okubo-Weiss parameter (OW), relative humidity (RH), and pouch- & deep-layer vertical shears (PShear, DShear) are evaluated within the area encompassed by the wave pouch following the pouch center at 12-hour forecast intervals up to 120 hours. Additional Lagrangian fields are computed, such as equivalent potential temperature (?e) as analyzed and forecast by HWRF-Genesis, and as predicted by horizontal advection of a conserved tracer (w/o sources and sinks). A new ingredient, not yet available publicly at the NPS/MRG website, is a depiction of satellite imagery in the co-moving frame of the pouch.
The NPS/MRG pouch products have been used successfully in several recent scientific field campaigns in the Atlantic and West Pacific (TCS08, PREDlCT/GRIP/lFEX 2010, HS3 2012). The HWRF-Genesis model has already been successfully incorporated into the NPS/MRG product suite during the 2011 and 2012 hurricane seasons. This proposal seeks to expand the diagnostic suite with a new objective technique and three additional visualization tools. The performance of the objective techniques will be compared with that of a standard HWRF-Genesis parameter to determine the improvement gained by incorporation into the marsupial framework. Inspection of the other three additional visualization tools will provide additional insights into the HWRF-Genesis handling of cyclogenesis. Finally, the inclusion of HWRF-Genesis in our multi-model ensemble of deterministic models will help us develop a formation probability forecast cone product.
Publications Publications, theses (not shown) and data repositories will be added to the portal record when information is available in FAIRS and brought back to the portal
Data Publications, theses (not shown) and data repositories will be added to the portal record when information is available in FAIRS and brought back to the portal