{"id":43407,"date":"2021-11-19T09:36:00","date_gmt":"2021-11-19T09:36:00","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=43407"},"modified":"2021-11-19T17:42:01","modified_gmt":"2021-11-19T17:42:01","slug":"comparing-nucaps-profiles-and-nam-nest-profiles","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/43407","title":{"rendered":"Comparing NUCAPS profiles and NAM Nest profiles"},"content":{"rendered":"\n
\"\"<\/a>
GOES-16 Nighttime microphysics RGB, VIIRS ACSPO SSTs and NUCAPS Sounding Availability points, 0806-0811 UTC on 19 November 2021 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n

Cold temperatures over the Great Lakes (the Green Bay 850-mb sounding temperatures, for example, were -11.9\u00ba C at 0000 UTC<\/a> and -8.1\u00ba C at 1200 UTC<\/a>) on 18-19 November 2021 generated extensive cloud cover and occasional snow showers. The nighttime microphysics RGB, above, showed extensive stratiform clouds downwind of Lake Michigan. The GOES-16 Cloud Top Phase product at this time (here<\/a>) uniformly showed water droplets over lower Michigan. <\/p>\n\n\n\n

Skies over eastern Lake Michigan were clear enough at 0811 UTC to allow some lake-surface temperature computations using NOAA-20 VIIRS channels and the ACSPO<\/a> algorithm. Diagnosed lake-surface temperatures are in the low 50s (\u00ba Fahrenheit; the colorbar range is 40\u00ba to 55\u00ba F).<\/p>\n\n\n\n

NUCAPS Sounding Availability points are also shown in the image above, and three points near\/over western Lake Michigan — near Escanaba MI<\/a>, east of Sheboygan WI<\/a>, and near Racine, WI<\/a> — are shown below.<\/p>\n\n\n\n

\"\"<\/a>
NUCAPS Profiles near Escanaba MI (left), east of Sheboygan WI (middle), and near Racine WI (right) (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n

NUCAPS profiles on this day over western Lake Michigan were uniformly warmer than 2-hour forecast NAM Nest profiles from the 0600 UTC model run. The image below compares (via Sharppy, using the NUCAPS in the Cloud methodology outlined here<\/a>) model (red and green lines) and NUCAPS (purple lines) near Escanaba. NUCAPS shows warmer low-level temperatures (and also cooler mid\/upper-tropospheric temperatures). Comparisons for the NUCAPS point east of Sheboygan and NAM Nest values at Sheboygan<\/a>, and the NUCAPS point near Racine and the NAM Nest values at Milwaukee<\/a> (note that for those two linked plots, the colors are flipped: NUCAPS Temperature and Dewpoint are red and green, respectively, and NAM Nest values are purple) are similar: NUCAPS values in the lowest part of the atmosphere are warmer than the NAM Nest. How might that affect the downwind production of lake-effect clouds and precipitation?<\/p>\n\n\n\n

\"\"<\/a>
Sharppy display showing NAM Nest profiles at Escanaba MI at 0800 UTC, a 2-h forecast from an 0600 UTC initial time (red: Temperature; green: dewpoint) as well as the nearby NUCAPS profile (purple) (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n

NUCAPS profiles give a model-independent estimate of temperature and dewpoint in the atmosphere. They are available about halfway (in time) between routine upper-air soundings in the lower 48 states of the USA. ‘NUCAPS Sounding Availability’ can be found under the ‘Satellite > S-NPP and NOAA-20’ menu.<\/p>\n","protected":false},"excerpt":{"rendered":"

Cold temperatures over the Great Lakes (the Green Bay 850-mb sounding temperatures, for example, were -11.9\u00ba C at 0000 UTC and -8.1\u00ba C at 1200 UTC) on 18-19 November 2021 generated extensive cloud cover and occasional snow showers. The nighttime microphysics RGB, above, showed extensive stratiform clouds downwind of Lake Michigan. The GOES-16 Cloud Top […]<\/p>\n","protected":false},"author":19,"featured_media":43408,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[78,83,5],"tags":[],"class_list":["post-43407","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-noaa-20","category-nucaps","category-winter-weather"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/43407","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\/19"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/comments?post=43407"}],"version-history":[{"count":6,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/43407\/revisions"}],"predecessor-version":[{"id":43423,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/43407\/revisions\/43423"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/43408"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=43407"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=43407"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=43407"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}