Large MCS affects Nebraska, Iowa, Kansas and Missouri
** GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing **A large Mesoscale Convective System (MCS) developed over eastern Nebraska late in the day on 16 June 2017, which continued to grow in size as it propagated southeastward and produced severe weather across western Iowa, northeastern Kansas and northwestern Missouri during the subsequent overnight hours (SPC storm reports). GOES-16 Infrared Window (10.3 µm) images (above) include plots of time-matched SPC storm reports; the report locations are parallax-corrected to match those of the cloud tops. The strong winds downed numerous trees and power lines; Kansas City Power & Light reported that as many as 93,000 customers — more than 10 percent — were without power within the utility’s service area (which covers 46 counties in Kansas and Missouri).
In a comparison of Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 0721 UTC or 2:21 am local time on 17 June (below), the Day/Night Band image showed a bright cluster of lightning streaks (cloud tops illuminated by intense lightning activity) straddling the Kansas/Missouri border. Note how the city lights of the Kansas City area were almost completely attenuated by the dense and vertically thick MCS core, while a diffuse signature of city lights was seen through the thin cirrus canopy around the edges of the storm. Packets of cloud-top gravity waves evident on both images, and the coldest cloud-top Infrared brightness temperatures were -85º C (darker violet color enhancement), located in both Kansas and Missouri.