SECTION 1: Summary of Graduate Student Research Activities (a) Distribution of Warm/Cool Season Precipitation Associated with 500 hPa Cutoff Cyclones

• Main Author: Matthew Scalora
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2008
• Subjects: Greenland; Hudson; Hudson Bay; Pacific
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.667.2723; http://cstar.cestm.albany.edu/CSTAR_docs/CSTAR-Report+11-24-08.pdf

progress. The first part of this research involved updating the 500 hPa cutoff low climatology performed by Smith (2003). The 6-h 2.5 ° x 2.5 ° NCEP–NCAR reanalysis grids and FORTRAN programs were used to extend this global and regional climatology. Figure 1 shows the total number of cutoff low events per grid point for 1948–2007. Maxima of cutoff low activity include the North Pacific Ocean, Hudson Bay, Canadian Maritimes, and off the coast of southeast Greenland. This climatology will be updated through 2008 after the conclusion of this year. Another important component of this project is to study several warm season cases of cutoff lows in the CSTAR domain using 6-h 0.5 ° x 0.5 ° GFS grids. These case studies will focus on the precipitation patterns of various cutoffs. Consistent with this focus, cases will be chosen that illustrate various problems with forecasting heavy precipitation and severe weather associated with cutoffs. Common synoptic-dynamic features throughout the troposphere will be composited along with selected parameters used in convective weather forecasting. Null cases, in which only nonsevere thunderstorms or light precipitation amounts occurred, also will be considered. Precipitation plots will be created from 6-h analyses obtained from the NWS National Precipitation Verification Unit Quantitative Precipitation Estimates.