MIMIC Total Precipitable Water fields for the 24 hours ending 1700 UTC on 21 January, above, show abundant moisture flowing into southern Alaska. Hourly GOES-17 infrared imagery (Band 13 clean window infrared imagery at 10.3 µm), below, shows a large cyclonic circulation to the south and west of Alaska that is helping to draw moisture towards the state. Level 2 Total Precipitable Water (TPW) is overlain on the imagery and two things stand out: because it is a clear-sky only product, and because the north Pacific Ocean is very cloudy on the 21st, there is little TPW information. Also, GOES-R Total Precipitable Water is not completely Full Disk; TPW is computed to a Local Zenith Angle of 67^o (ATBD) and you can see the cut-off for the product in northwestern Canada. Those two things argue for the utility of microwave detection of moisture over Alaska, as shown above.

Much of Alaska Southeast from Yakutat to Wrangell is under a Flood Watch. (Image, taken from this site)

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The Community Satellite Processing Package (CSPP) Algorithm Integration Team (AIT) has released a new version of processing software that creates (using updated Enterprise algorithms) Level 2 GOES-R products from radiance products. It also includes processing to provide Quick Look imagery for those products; that is, if you have the processed Level 2 product files, you can display them. One example is shown above, Cloud Top Phase from 1401 UTC on 20 January 2022.

The processing package is available here (a quick easy registration may be required): Look for “AIT Framework V2.0beta4 Software for Linux” and download the gzipped tar file. Note also that documentation is also available (link). Per that documentation, I downloaded the software into a directory that I changed directories to, and I put that directory at the front of my unix PATH, i.e., export PATH=”$PWD:$PATH”. Then I used the aitf-ql (“ql” for quick-look) command:

aitf-ql /path/to/directory/holding/L2products/ACTPC/*s20220201401*.nc --image_size 2560.0 1920. -o /home/scottl/

I have specified both the image size, and the output directory. If you have access to L2 imagery (in NOAA CLASS, for example), this is an easy way to view the imagery. Note that this software will also create QuickLooks from ABI radiance files, as the GOES-17 example below shows. You can create imagery for computed brightness temperature (Bands 7-16) or reflectance (Bands 1-6).

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GOES-16 (GOES-East) Mid-level Water Vapor (6.9 µm) images (above) revealed the formation of a standing wave cloud along the Minnesota shoreline of Lake Superior on 19 January 2022. This cloud feature was formed by a vertically-propagating internal gravity wave that resulted from the interaction of strong post-cold-frontal northwesterly winds with the topography of the shoreline — the terrain quickly drops from an elevation of about 2000 feet above sea level (over northeastern Minnesota) to about 600 feet above sea level (over Lake Superior) in a very short distance.

In a toggle between GOES-16 Water Vapor and Suomi-NPP VIIRS Infrared Window images at 1811 UTC (below), the coldest cloud-top infrared brightness temperatures were around -40ºC (lime green enhancement).

A northwest-to-southeast oriented cross section of RAP40 model fields along line segment F-F’ (below) showed a deep pocket of positive Omega (upward vertical motion, yellow to red colors) that corresponded to the cloud band along Minnesota’s Lake Superior shoreline. Note that this Omega feature was vertically tilted in an “upshear” direction (toward the northwest), and extended upward to the 500 hPa pressure level. The depth and magnitude of this positive Omega decreased with time, leading to the dissipation of the standing wave cloud.

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GOES-16 (GOES-East) Day Snow-Fog RGB images (above) displayed widespread streamers of blowing snow (pale shades of white) across much of North Dakota and far northwestern Minnesota on 18 January 2022. Blowing snow was lofted from the surface by elongated horizontal convective rolls that developed in the wake of a strong cold frontal passage — surface winds gusted to 58 knots (67 mph) at Garrison in western North Dakota, and the surface visibility was reduced to zero at several locations. An arctic air mass behind the cold front helped the surface temperature drop to -22º F at Willow City, ND the following morning.

A more uncluttered view — without plots of surface reports — is shown below (Interstates and major highways are plotted in gray). Some secondary highways were closed due to the ground blizzard conditions.

Here were the latest road conditions as of 7 pm. Wind speeds were finally beginning a slow decrease. #ndwx #mnwx pic.twitter.com/36ExfahP7k

— NWS Grand Forks (@NWSGrandForks) January 19, 2022

Here is a look at the highest wind gust reports from today. #ndwx pic.twitter.com/vboUpzToRt

— NWS Bismarck (@NWSBismarck) January 19, 2022

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