GOES-East upper level (6.2 um) water vapor imagery with GLM and RAP analysis overlay depicted the Friday night – Sunday morning evolution of a storm system that brought severe thunderstorms to the southern US (Figure 1). A closed upper low initially centered over southern California on Friday accelerated east across northern Mexico Saturday as it evolved into an open wave, and eventually progressed ENE into the southern plains and southeast Sunday into Monday morning. Water vapor imagery shows the drying/warming descending air (warm colors) wrapping around the southern portion of the strengthening shortwave in conjunction with the intense upper level jet. Strong ascent is apparent east/northeast of the upper energy below the exit region of the upper jet represented as regions of cooling (cool colors and white) and developing thunderstorms. The RAP overlays help one to conceptualize what is being observed in the more detailed (temporally and spatially) water vapor imagery.

Additionally in Figure 1, a shortwave trough is diagnosed digging southeast across the northwest US Saturday and then east across Colorado into the central high plains on Sunday as it swings around the base of a broad upper low slowly sinking south into the far north-central US. This system brought a swath of snowfall to the Rockies, central high plains, and into the Midwest, which is apparent in the GOES-East Day Cloud Phase Distnction RGB as green (Fig 2).

Visible/GLM FED Sandwich combo imagery with NWS warning polygons during the daytime shows the development and evolution of thunderstorms throughout the day, and the relationship between lightning activity and strong (warned) storms (Fig 3). GLM is effective in highlighting the location of updraft cores and updraft trends within a messy cloud field and long flashes extending outward from the main updrafts and into the anvils. The image combination includes quantitative information from GLM without sacrificing the vital texture information from the VIS.

Bill Line, NESDIS and CIRA