A storm named Eunice has developed over the British Isles and is causing severe winds, up to 122 mph observed at the surface. The storm is associated with a very active jet stream in the North Atlantic. Eunice follows another storm, Dudley, that hit England, Ireland, and Scotland on Wednesday 2/16/22 and brought heavy winds and flooding.

ECMWF produced a short write-up on this storm, and two others that week (link).

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GOES-16 Dust RGB and Split Window Difference (10.3-12.3 µm) images, along with topography [click to play animated GIF | MP4]

GOES-16 (GOES-East) Dust RGB and Split Window Difference (10.3-12.3 µm) images (above) revealed a pulse of blowing dust (or haboob) that was created by strong surface outflow from collapsing thunderstorms near the California/Nevada border on 15 February 2022. Much of this wind-lofted dust (appearing as brighter shades of magenta in Dust RGB images, and brighter shades of yellow to green in Split Window Difference images) was then channeled southward through the lower elevations of Death Valley, California — reducing the visibility to zero and causing power outages (Local Storm Report).

A toggle between GOES-16 Dust RGB and Split Window Difference images at 2156 UTC (along with topography) is shown below.

GOES-16 Dust RGB and Split Window Difference (10.3-12.3 µm) images at 2156 UTC, along with topography [click to enlarge]

The blowing dust was also evident in GOES-16 True Color RGB images created using Geo2Grid (below) .

GOES-16 True Color RGB images [click to play animated GIF | MP4]

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The sharp eye of Rick DiMaio notes a change in Lake Erie ice coverage from a port in Ontario and then around Long Point. Information from this website suggests this is the tanker Algonorth! Follow this ship today at your favorite website that shows GOES-16 animations! For example: CSPP Geosphere ; CIRA Slider. (Update the times as needed!)

This website (link) can be used to track this ship. Here is the path through 2000 UTC on 14 February 2022, in agreement with the imagery above (and below). The ship (with a draught of 7.6 m) is bound for Sarnia, Ontario (ETA at 1600 UTC on 15 February), on the south shore of Lake Huron where the St. Clair River starts. There is a lot of ice between its present position and there!

An updated loop (through 2126 UTC) is shown below. The obvious wake through the ice becomes much less obvious during the day, suggesting that the ship is passing through thicker and thicker ice.

Something similar happened on 15 February as well, with a ship (an icebreaker) leaving Cleveland.

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GOES-16 Cryosphere products — Ice Mask, Ice Concentration and Ice Surface Temperature — have been developed and are in a testing phase. The AWIPS screenshot above shows ice concentrations over parts of Lakes Superior, Huron and Erie. These products are created over the Full Disk ABI domain in regions of clear sky only (clouds over Lakes Michigan and Ontario mean Ice Concentration is not computed there at 1300 UTC). The Ice Mask at the same time, below, shows ‘Day Ice’ (cyan) and ‘Night Ice’ (green) flags; cryosphere products are created day and night, but different algorithms are used: Bands 14 and 15 (11.2 µm and 12.2 µm, respectively) are used day and night; the daytime product also uses Bands 2, 3 and 5 (at 0.64 µm, 0.86 µm and 1.61 µm, respectively) as noted in the Advanced Theoretical Basis Document — ATBD — here.

The strength of ABI is frequency (every hour) of observations, so an animation, as shown below, will allow a user multiple views of the lakes; in partly cloudy (or clearing) conditions, values from one hour can augment values from other hours. An example is shown below with Ice Concentration over the Great Lakes. Clearing skies over Lake Erie allow for a more complete description of Lake Ice, whereas increasing clouds over western Ontario and western Lake Superior mean GOES-R Cryosphere observations are lost. In the absence of very strong winds, however, lake ice does not erode quickly, so although the observations are precluded by cloud cover, earlier observations likely remain valid. It is important to know where the clouds are, however, when viewing these products.

The utility of these clear-sky products with good temporal frequency is augmented in combination with all-sky products that give observations only once or twice daily — such as Synthetic Aperture Radar (SAR) ice observations that available here. For example, the 2307 UTC 13 February Normalized Radar Cross Section (NRCS) image (below) over eastern Lake Erie can be used to fill in information not available from the GOES-16 Cryosphere product.

The AWIPS toggle below shows Ice Surface Temperature plotted below and on top of the Binary Cloud Mask. You will note that there are regions where Ice Surface Temperature is computed in regions where the Binary Cloud Mask shows clouds! How can this occur in Clear Sky products such as the Cryosphere products (a similar toggle could be created with Ice Concentration or Ice Mask)?

The Cloud Mask in AWIPS shows regions that are Clear or Cloudy — it is binary. The Cloud Mask actually has 4 different states (as noted here): Clear, Probably Clear, Probably Cloudy and Cloudy. The Cloud Mask in AWIPS assigns ‘Cloudy’ to all pixels that aren’t Clear: that includes ‘Probably Clear’, ‘Probably Cloudy’ and ‘Cloudy’ pixels. In contrast, the Cryosphere products are produced in regions that are both Clear, or Probably Clear (as noted in the ATBD). That’s why Cryosphere products can show up in regions that AWIPS shows are Cloudy.

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