A nighttime mesoscale convective system (MCS) developed near the Arkansas/Louisiana/Mississippi border region after about 0700 UTC (2:00 AM local time) on 11 August 2015, and began to move southeastward. A comparison of 4-km resolution GOES-13 Infrared (10.7 µm) and 375-meter resolution Suomi NPP VIIRS Infrared (11.45 µm) images (above) showed the MCS around 0845 UTC, and highlighted the two advantages of polar-orbiter vs geostationary satellite imagery: (1) higher spatial resolution, for a more accurate assessment of the cloud-top IR Brightness Temperatures (the coldest GOES-13 IR BT was -73º C, while the coldest VIIRS IR BT was -83º C), and (2) minimal parallax error, for a more accurate geo-location of features such as thunderstorm overshooting tops (note how the storm appeared to be located farther to the northwest on the GOES image, centered over far southeastern Arkansas).

With the arrival of daylight the following morning, 1-minute interval GOES-14 SRSO-R visible (0.63 µm) images (below) revealed the presence of numerous short-lived overshooting tops which were penetrating the cirrus canopy of the persisting MCS. The formation of a well-defined outflow boundary was also seen, which continued to move southward during the late morning hours. The MP4 movie file is also available as a very large (73 Mbyte) animated GIF. A GOES-14 1-minute-image IR (10.7 µm) animation which shows the initial development and subsequent motion of the MCS can be seen here.

GOES-14 1-minute visible images (below) also showed the development of multi-cellular thunderstorms over parts of the Mid-Atlantic states, focused along trough axes ahead of an approaching cold frontal boundary — many of these thunderstorms produced damaging winds (SPC Storm Reports). The MP4 movie file is also available as a very large (102 Mbyte) animated GIF.