Convective Meteorology (Mesoscale Dynamics)

A number of novel techniques to examine polarimetric radar data collected via PPI scans in a time-height format have been developed in recent years. Using primarily polarimetric radar data collected by WSR-88D radars, techniques such as quasi-vertical profiles (QVPs), range-defined quasi-vertical profiles (RD-QVPs), and column vertical profiles (CVPs) have been used to investigate the vertical structure of precipitating systems such as winter storms, mesoscale convective systems, and landfalling hurricanes.

TBD     NWC 5600

TBD   NWC 5600

Numerical weather prediction models often fail to correctly forecast convection initiation (CI) at night in the Great Plains. To improve our understanding of such events, researchers collected unique observations from thermodynamic and kinematic profilers as part of the Plains Elevated Convection at Night (PECAN) experiment. The assimilation of these observations can aid in analyses of key features that are not easily observed by conventional datasets This talk presents forecasts of a nocturnal CI event from PECAN in which assimilating the PECAN dataset improves the timing, location, and orientation of CI.

TBD   NWC 5600

Day-ahead (20 – 22 hour) 3-km grid spacing convection-allowing model forecasts are performed for a severe hail event on 8 May 2017 using six different multi-moment microphysics (MP) schemes including: the Milbrandt and Yau double-moment (MY2), Thompson (THO), NSSL double-moment (NSSL), Morrison double-moment graupel (MOR-G) and hail (MOR-H), and Predicted Particle Properties (P3) schemes.

TBD     NWC 5600

In a previous study, Chen and Snyder (2007) showed that a large location error in the background forecast can result in a poor performance of ensemble Kalman filter (EnKF) data assimilation (DA) due to the violation of the Gaussian assumptions.  One way to alleviate this issue is to apply vortex relocation (VR) before the ensemble-based DA.

TBD   NWC 5600

TBD     NWC 5600