![\"GOES-13](\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2013\/11\/131104_g13_vis_distrails_lake_ontario_anim.gif\" "\\"GOES-13")
<\/a>GOES-13 Visible (0.63 \u00b5m) images [click to play animation]<\/p><\/div>Hat tip to NWS Buffalo NY<\/strong><\/a> forecasters Jon Hitchcock and David Zaff for letting us know about a number of aircraft dissipation trails (also known as “distrails” or “hole punch clouds”)<\/em> over the Lake Ontario region on 04 November 2013<\/strong><\/a>. A series of McIDAS images of 1-km resolution GOES-13 Visible (0.63 \u00b5m) data (above)<\/strong><\/em> showed these features as they drifted eastward during the day.<\/p>\n A comparison of AWIPS II images of 375-meter resolution Suomi NPP VIIRS Visible (0.64 \u00b5m) visible and the corresponding False Color “Snow Cloud Discrimination” Red-Green-Blue (RGB) at 18:17 UTC (below)<\/strong><\/em> indicated that the cloud layer penetrated by aircraft was composed of supercooled water droplets (which appear as brighter shades of white on the RGB image)<\/em> — but the particles in the aircraft exhaust acted as ice nuclei and caused the cloud to glaciate (ice crystal clouds appear as varying shades of red on the RGB image)<\/em>.<\/p>\n Suomi NPP VIIRS Visible (0.64 \u00b5m) and “Snow\/Cloud Discrimination RGB” images [click to enlarge]<\/p><\/div>AWIPS images of the POES AVHRR CLAVR-x<\/strong><\/a> Cloud Type product confirmed that the cloud layer over the Lake Ontario region was a supercooled water droplet cloud (green color),<\/em> with the Cloud Top Height product indicating tops in the 7-9 km range (below)<\/strong><\/em>. However, higher-altitude cirrus clouds were beginning to overspread the region from the west (Cirrus=orange; Thick Ice=yellow; Overlap=violet)<\/em>.<\/p>\n<\/a>