The impact of GLOW wind profile data on numerical simulation of a warm season convection observed during IHOP_2002

The importance of moisture fields in the initiation and evolution of mesoscale convective systems has been well recognized and is actively being studied. However, the influence of wind measurements on numerical predictions of mesoscale convective systems has not been given much attention. This study examines the impact of assimilating multi-time wind profiles over a single station on the numerical simulation of a warm season mesoscale convection system over the region from the Kansas and Oklahoma border to the Texas Panhandle, observed 12-13 June 2002 during the International H2O Project (IHOP_2002). Wind profile observations, obtained from Goddard Lidar Observatory for Winds (GLOW) are assimilated into an advanced research version of the weather research and forecasting (WRF) model using its four-dimensional variational (4DVAR) data assimilation system. Results indicate that the assimilation of high temporal and vertical resolution GLOW wind profiles have a significant influence on the numerical simulation of the convective initiation and evolution. Not only the wind fields but also the structure of moisture fields associated with the convective system are improved. Data assimilation has also resulted in a more accurate prediction of the structure, location and timing of the convection; as a consequence, the skill of quantitative precipitation forecasting is enhanced.

The study is in progress to compare the relative impact of GLOW wind profiles with available sonde wind profiles. Further study of the impact of the wind and water vapor mixing ratio from a Raman lidar is in progress. Results will be presented in the conference.