{"id":7898,"date":"2011-04-25T23:58:40","date_gmt":"2011-04-25T23:58:40","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=7898"},"modified":"2011-04-27T02:27:08","modified_gmt":"2011-04-27T02:27:08","slug":"what-the-heck-is-this","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/7898","title":{"rendered":"What the heck is this?"},"content":{"rendered":"
\"GOES-13<\/a>

GOES-13 6.5 \u00c2\u00b5m "water vapor channel" images (click image to play animation)<\/p><\/div>\n

We received the following in an email message from Paul Fuentes at the National Weather Service forecast office at Key West, Florida:<\/p>\n

“Just though you might be interested in a peculiar little feature we noticed at the WFO Key West on AWIPS from GOES-13 IR imagery on 4\/23\/11 starting at about 22:301Z over Andros Island (24.21N, 77.7W) and persisted to into the afternoon on 4\/24\/11. The feature looked almost like a smoke ring (several miles across) that was drifting off to the Northeast that emanated off of Andros Island and was also apparent in VIS\/WV.”<\/p><\/blockquote>\n

McIDAS images of 4-km resolution GOES-13 6.5 \u00c2\u00b5m “water vapor channel” data (above)<\/em><\/strong> showed the feature in question, as it first appeared along the east coast of Andros Island (the large island in the lower left corner of the images)<\/em> at 22:45 UTC on 24 April 2011<\/a><\/strong> — and then propagated northeastward, grew in size, exhibited progressively colder brightness temperatures, and at times took on a ring-like shape.<\/p>\n

A closer look using 1-km resolution GOES-13 0.63 \u00c2\u00b5m visible channel images (below)<\/em><\/strong> again revealed the ring-like structure that was evident at various times during the day on 25 April 2011<\/a><\/strong>.<\/p>\n

\"GOES-13<\/a>

GOES-13 0.63 \u00c2\u00b5m visible channel images (click image to play animation)<\/p><\/div>\n

The feature (as seen on 10.8 \u00c2\u00b5m POES AVHRR IR imagery, below)<\/em><\/strong> seemed to follow the CRAS model 300 hPa wind flow — and southwesterly winds were not found until the 375 hPa pressure level on the 12 UTC rawinsonde report<\/a><\/strong> from Nassau in the Bahamas.<\/p>\n

\"POES<\/a>

POES AVHRR 10.8 \u00c2\u00b5m IR images + CRAS model 300 hPa wind flow<\/p><\/div>\n

A comparison of the MODIS 0.65 \u00c2\u00b5m visible channel, the 11.0 \u00c2\u00b5m IR window channel, the 6.7 \u00c2\u00b5m water vapor channel, and the 1.3 \u00c2\u00b5m cirrus detection channel images at 15:57 UTC (below)<\/em><\/strong> seem to support the idea that this was a high ice cloud feature.<\/p>\n

\"MODIS<\/a>

MODIS visible, IR window, water vapor, and cirrus detection channel images<\/p><\/div>\n

So what exactly was this interesting satellite feature? Until an explanation is found, this blog posting shall remain in the “What the heck is this?” Category…<\/p>\n","protected":false},"excerpt":{"rendered":"

We received the following in an email message from Paul Fuentes at the National Weather Service forecast office at Key West, Florida: “Just though you might be interested in a peculiar little feature we noticed at the WFO Key West on AWIPS from GOES-13 IR imagery on 4\/23\/11 starting at about 22:301Z over Andros Island […]<\/p>\n","protected":false},"author":18,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[22,11,12,26,38],"tags":[],"class_list":["post-7898","post","type-post","status-publish","format-standard","hentry","category-avhrr","category-goes-13","category-modis","category-poes","category-what-the-heck-is-this"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/7898","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/users\/18"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/comments?post=7898"}],"version-history":[{"count":6,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/7898\/revisions"}],"predecessor-version":[{"id":7900,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/7898\/revisions\/7900"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=7898"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=7898"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=7898"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}