GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed a string of mesovortices over the eastern portion of Lake Superior, along with a small, isolated mesovortex just offshore in the western portion of Lake Superior on 13 February 2022. Increasing ice coverage was also seen along the edges of the lake.

Farther to the east, GOES-16 Visible images showed a large and well-defined mesovortex over Lake Huron, with smaller mesovortices along a northern Lake Michigan cloud band (below).

Finally, over southern Lake Michigan a distinct mesovortex developed along the southern end of a long lake cloud band that began to move inland across far southwestern Lower Michigan (below).

A closer look at the Lake Michigan vortex using 1-minute Mesoscale Domain Sector GOES-16 Day Cloud Phase Distinction RGB images (below) portrayed the shades of green indicative of glaciating convective clouds around the core of the mesovortex and the trailing Lake Michigan band. The confluence of the western periphery of the mesovortex with the trailing lake cloud band produced a prolonged period of heavy snow at Benton Harbor (KBEH) and up to 12 inches of snowfall at downwind locations in Berrien County, Michigan.

In a sequence of 1-minute GOES-16 Cloud Top Phase Distinction RGB and Cloud Top Phase derived product images from 2000-2100 UTC (below), the supercooled/mixed phase core of the inland mesovortex was surrounded by a ring of ice phase clouds — while the adjoining Lake Michigan cloud band was classified as a mixed-phase feature as it began to move inland.

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GOES-16 (GOES-East) Day Snow-Fog RGB images (above) showed the signature of widespread horizontal convective rolls — which highlighted areas where blowing snow was creating ground blizzard conditions — across parts of eastern North Dakota and far western Minnesota on 11 February 2022. The elongated bands of blowing snow were more concentrated where they were being channeled by strong northerly winds through the lower elevations of the Red River Valley (peak wind gusts included 60 mph in North Dakota and 56 mph in Minnesota). The surface visibility was briefly reduced to near zero at reporting sites such as Crookston MN (KCKN) and Wahpeton ND (KBWP).

A closer view using 1-minute Mesoscale Domain Sector GOES-16 Day Snow-Fog RGB images (below) showed portions of Interstate 29 (between Grand Forks KGFK and Fargo KFAR) and Interstate 94 (between Jamestown KJMS and Fargo KFAR) that were impacted by these bands of blowing snow.

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This event is also discussed at the Satellite Liaison Blog (link).

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This presentation from the TOWR-S Satellite Book Club details TOWR-S RPM 22 additions to AWIPS (additions spearheaded by Tim Schmit and Bill Line, both from NOAA/STAR) that add Level 2 product readouts to RGBs in AWIPS. Thus, for example, the Airmass RGB, above, is underlain by Level 2 products: Cloud Mask and Total Precipitable Water (TPW) and Level 2 Stability Indices (CAPE and Lifted Index). Those Level 2 products are all clear-sky only, however, so sampling in cloudy regions will not yield level 2 product information.

Adding Gridded NUCAPS fields (in the example above and below, total precipitable water has been added; one could also add CAPE and Lifted Index), is an effective way of including estimates of atmospheric thermodynamics in clear and cloudy regions that can then be sampled, as shown below with two sampling examples, one each in clear and cloudy skies. The sampling location is just northwest of the Clear Sky Mask value (i.e., the screen capture did not capture the cursor).

An efficient way to load these data in AWIPS is via a procedure. The augmented RGB loads are part of TOWR-S RPM 22.

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Suomi-NPP VIIRS Visible (0.64 µm) images (above) revealed numerous cloud plumes that were emanating from natural gas flaring sources at oil drilling sites across the North Slope of Alaska on 08 February 2022. Surface air temperatures were around -50°F in that area, with Deadhorse setting a daily record low of -53°F.

A sequence of Suomi-NPP VIIRS Visible (0.64 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images is shown below. The cloud plumes appeared significantly warmer in the 3.74  µm images due to reflected incoming solar radiation — and warmer in the 11.45 µm images since those cloud tops were located within the warmer air aloft of a pronounced boundary layer temperature inversion (00 UTC Utqiagvik/Barrow rawinsonde plot | text).

A closer view of the Suomi-NPP VIIRS Shortwave Infrared image at 2339 UTC (below) included a cursor readout, which indicated gas flaring point source infrared brightness temperatures as warm as +21.6°C (orange pixels).

In a sequence of nighttime to dawn VIIRS Day/Night Band (0.7 µm) and daytime False Color RGB images from NOAA-20 and Suomi-NPP visualized using RealEarth (below), a larger/brighter gas flaring signature was evident about 4 hours prior to sunrise at the point source of the cloud plumes (intermingled with numerous smaller flaring signatures).

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Carl Dierking from GINA at the University of Alaska Fairbanks noted this event as well, discussed here. The toggle above compares a VIIRS Day Land Cloud RGB and a later Day Night Band image. A light source (that is, burning flares) exists at the head of each cloud plume.

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