A comparison of AWIPS images of 1-km resolution MODIS 0.65 Âµm visible channel, 11.0 Âµm IR channel, and 6.7 Âµm water channel data (above) revealed subtle Kelvin-Helmholtz (K-H) billow features across parts of eastern Iowa on 10 February 2013 that were only apparent in the water vapor imagery. In the vicinity of these elongated mesoscale wave signatures, there were a few pilot reports of light to moderate turbulence (primarily within the 14,000-21,000 foot altitude range).
An animation of 4-km resolution GOES-13 6.5 Âµm water vapor images (below) did not show any evidence of these K-H billow features within the dry slot that was wrapping around the center of a large and intense winter storm that was producing blizzard conditions from Nebraska to North Dakota.
A comparison of the 1-km resolution MODIS water vapor image with the corresponding 4-km resolution GOES-13 water vapor image (below) demonstrated the advantage of improved spatial resolution for the detection of such potentially-important mesoscale features. The slight northwestward shift of features seen on the GOES-13 water vapor image is due to parallax.