A toggle between NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images valid at 0805 UTC or 2:05 AM CST on 12 November 2022 (above) showed a broad plume of lake effect clouds streaming south-southwestward from Lake Nipigon, Ontario (north of Katatota Island, station CWKK) toward Lake Superior. A strong northeasterly flow of cold air across the still-unfrozen Lake Nipigon was helping to create this plume of lake effect clouds.

During the subsequent daytime hours, GOES-16 True Color RGB images from the CSPP GeoSphere site (below) displayed the lake effect snow (LES) bands that were streaming southwestward from Lake Nipigon and across the western portion of Lake Superior. The dominant LES band produced snowfall amounts as high as 10 inches in western Upper Michigan and 13.8 inches in northwestern Wisconsin.

GOES-16 Day Cloud Phase Distinction RGB images (below) suggested that there was some glaciation of the dominant LES band, as indicated by the shades of yellow to green.

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A comparison of GOES-16 Day Cloud Phase Distinction RGB, Cloud Top Pressure, Cloud Top Height, Cloud Top Phase and Cloud Optical Depth at 1756 UTC (above) highlighted the southern portion of the dominant LES band that produced the heaviest snowfall reports in Upper Michigan and northwestern Wisconsin.

Cursor-sampled values of GOES-16 Day Cloud Phase Distinction RGB components, Cloud Top Pressure, Cloud Top Height and Cloud Top Phase (below) showed typical values of those parameters along the dominant LES band at 1756 UTC.

Cursor-sampled values of Level 2 Derived Products (such as Cloud Top Phase and Cloud Top Height) can also be obtained directly from RGB imagery — in this case, Day Cloud Phase Distinction (below) — using an AWIPS “Local Menu Items” option, as discussed in this Satellite Book Club presentation.

Animations of GOES-16 Cloud Top Pressure, Cloud Top Height, Cloud Top Phase and Cloud Optical Depth derived products during the period from 0001-1956 UTC on 12 November are shown below. Note that Cloud Optical Depth values are only displayed across the southern part of the satellite scene, since the operational version of this product is only created for pixels having a local solar zenith angle of 65 degrees or less (and the November sun angle was low across that region).

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RADARSAT-2 overflew Guam early on 10 November 2022, and the toggle above shows both Himawari-8 imagery at that time with the SAR wind estimates overlain. This was a time of light winds and minimal shower activity. It’s interesting that the wake of weak winds downwind of the islands of Guam (and Rota) are apparent in this regime of weak easterly winds. (Metop-B ASCAT winds from late on 9 November are here, and late on 10 November are here; both images are from the NOAA/NESDIS ‘manati’ website).

A zoomed-in version of the image above is shown below. The windspeed downwind of Guam shows downstream variations in speed, oriented north-south. Those speed changes are very small, from 11-12 knots (cyan enhancement) to 8 or 9 knots (dark blue) enhancements. The coldest cloud tops in the Himawari-8 imagery — to the west of Guam — are associated with strong/weak wind dipoles. The region of stronger winds (around 18 knots, green in the enhancement used) to the west-northwest of Guam are associated with slightly cooler cloud tops, but this line of tropical convection has brightness temperatures in the 15-18^oC range: not very tall at all!

Imagery is also available at the NOAA/NESDIS STAR SAR Winds calendar here; the wind speed and the Normalized Radar Cross Section information are both available, and they are shown in a toggle below.

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Day Night Band imagery from NOAA’s AOML Direct Broadcast site, above, shows a low-level circulation with deep convection over the center at 0719 UTC. GOES-16 Low-Level water vapor (Band 10, 7.3 µm) mesoscale sector one imagery, below, (from this website) shows abundant mid-level dry air to the south of the Nicole. Nicole is near a dry environment.

Nicole’s path, shown below, (from this website), is along a corridor of low shear, and towards the warm waters of the Gulf Stream.

A true-color visible mp4 animation, below, from the CSPP Geosphere site, (direct link to animation) shows the center of Nicole very close to dryer air to the south. This proximity to dry air argues against rapid intensification.

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Nicole does have a very large windfield. HY-2C scatterometery, above, (from this website), show the very large region of tropical storm-force winds over much of the South Atlantic Bight, from the Bahamas up to Cape Hatteras! Coastal erosion and flooding from the wind and generated waves (in addition to storm surge) is likely, and residents along the coast should heed advisories/warnings.

For more information on Nicole, refer to the National Hurricane Center website.

10 November Update: Hurricane Nicole made landfall along the coast of Florida around 0800 UTC on 10 November, producing wind gusts as high as 75 mph.

#VIIRS Day/Night Band and Infrared images from @NOAASatellites #NOAA20 valid at 0707 UTC (2:07 AM EST) showed Hurricane #Nicole about 53 minutes prior to landfall near Vero Beach, Florida: https://t.co/JoLBqn1hcc #FLwx pic.twitter.com/0vJmkTHXLt

— Scott Bachmeier (@CIMSS_Satellite) November 10, 2022

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The Day Night band on Suomi NPP and on NOAA-20 (and on the soon-to-be-launched JPSS-2 that will become NOAA-21) rely on reflected moonlight to provide crisp imagery of clouds. When a lunar eclipse occurs, as happened early on 8 November 2022, lunar illumination is lost. The lunar eclipse of 8 November started at 0803 UTC, with totality from 1017 to 1142 UTC, and the eclipse ended 1249 UTC. (Details are here.)

The toggle above shows Suomi NPP and NOAA-20 imagery (from the VIIRS Today website); when Suomi NPP overflew the east coast (at around 0700 UTC, viewing Tropical Storm Nicole to the east of Florida) and the midwest (around 0830 UTC), the lunar eclipse had not yet started, or its effects were minimal (here is a map of Suomi NPP orbital paths). NOAA-20 overflew the midwest 90 minutes after Suomi NPP when the Lunar Eclipse was starting to reduce illumination. For both satellites, the overflights over the western US occurred during totality; lunar illumination was minimal.

Previous lunar eclipses are discussed here, here and here.

In a sequence of #VIIRS Day/Night Band images from #SuomiNPP & #NOAA20, the loss of illumination from the Full Moon during #lunareclipse2022 was evident over the western US & Pacific Ocean during eclipse totality: https://t.co/0HH347ehe1 More info: https://t.co/Fml9vRH19H pic.twitter.com/NxdP86tgwW

— Scott Bachmeier (@CIMSS_Satellite) November 8, 2022

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