30-day loop of analyzed 500-hPa heights and anomalies. Each frame is an five-day mean, centered on the date indicated in the title, of 500-hPa heights and anomalies from the NCEP Climate Data Assimilation System (CDAS).  Contour interval for heights is 120 m, anomalies are indicated by shading.   Anomalies are departures from the 1991-2020 daily base period means.