Seasonal LargeScale Environments Associated with Mesoscale Convective Systems

Seasonal Large-Scale Environments Associated with Mesoscale Convective Systems over the U. S. Great Plains ● ● ● ● Objective Identify favorable and unfavorable large-scale environments associated with mesoscale convective systems (MCSs) during spring and summer. Quantify the predictive power of favorable environments for MCSs number, rain rate, and rain area. Approach Track MCSs based on radar and satellite datasets using a recently developed MCS tracking algorithm. Composite and identify the large-scale environments where MCSs initiate using a self-organizing map (SOM) analysis. Correlate large scale environments and SOM identified favorable environments using a large-scale index. Impact Provided insights on different environments where MCSs form and why MCSs are less predictable in summer versus spring in the U. S. Great Plains. Quantified the variance of MCS number, rain rate, and rain area explained by the favorable large-scale environments to provide insights for future MCS predictions. Mesoscale convective system (MCS) wind and specific humidity anomalies during March-April-May (MAM) in each type of favorable large-scale environment as determined by self-organizing map. Understanding the large-scale environments associated with MCSs is important for current predictions and future variability in environmental changes. Song F, Z. Feng, L. R. Leung, R. A. Houze, J. Wang, J. Hardin, C. Homeyer, 2019: Contrasting spring and summer large-scale environments associated with mesoscale convective systems over the U. S. Great Plains, Journal of Climate, 32 (20), 6749 -6767, DOI: 10. 1175/JCLI-D-18 -0839. 1.