A sequence of GOES-16 (GOES-East) “Red” Visible (0.64 µm), Day Cloud Phase Distinction RGB and Day Snow-Fog RGB images (above) showed widespread fog/stratus across parts of Montana, North/South Dakota and Minnesota during the day on 06 January 2023. With a quasi-stationary area of high pressure located over that area (surface analyses), winds remained light and the fog/stratus layer was slow to dissipate over much of the region (where snow cover was generally in the 10-20 inch range). The surface visibility was near zero at some sites, with scattered reports of freezing fog and/or light snow.

Plots of rawinsonde data from Bismarck ND (KBIS) and Aberdeen SD (KABR) are shown below — both sites indicated that a strong and moist boundary layer temperature inversion remained in place during the day, which also helped the fog/stratus layer to persist or dissipate rather slowly. Judging from the pressure level of sharp dew point decreases, these fog/stratus features were confined to altitudes of 1200-1400 meters (3900-5000 feet) or lower.

GOES-16 Day Snow-Fog RGB images at 1901 UTC — with an overlay of the corresponding CLAVR-x and Operational versions of the Cloud Top Height (CTH) derived product — include cursor-sampled those two Cloud Top Height values at Bismarck ND (above) and Aberdeen SD (below). It would appear that the 10-km resolution Operational CTH values were unrealistically high — which can often occur over areas with snow cover — compared to the 2-km resolution CLAVR-x CTH values (the full-resolution CLAVR-x products are produced at CIMSS).

A comparison of GOES-16 Day Snow-Fog RGB image, CLAVRx Cloud Top Height and Operational Cloud Top Height derived products at 1901 UTC is shown below.

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From GOES-A (1) in 1975, to GOES-T (18) launched in 2022! On January 4, 2023 GOES-18 is operational as GOES-West, here’s a look-back at all the GOES. Note that the GOES-R series imagers support the generation of a true color image, given they have the blue (or 0.47 micrometer) band. Continuity is critical for operational satellites and this shows the case, as well as these GOES satellite timeline from this CIMSS Satellite Blog post. A glimpse into a bit of what the GOES ABI observed in 2022.

The GOES-18 thumbnail is when the satellite was at its initial check-out location.

More on the “high noon” geostationary imager composite from UW/SSEC, which now includes the GOES-18 ABI.

All the NOAA GOES data for the thumbnails have been accessed via the University of Wisconsin – Madison SSEC Satellite Data Services. The Full Disk images were made using McIDAS-X software, and combined with a series of ImageMagik commands.

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Heavy rains have finally hit California, which declared a state of emergency on Wednesday January 4 due to extreme rainfall amounts. The GOES-West enhanced Band 9 imagery (6.9 µm, mid-level water vapor) illustrates how moisture associated with the recent similar Trans-Pacific atmospheric river generated heavy rainfall for much of California, Oregon, and Washington. Overlayed with NEXRAD radar reflectivity, the animation below paints a good picture of the rainfall that accumulated within the 21 hours shown.

The California Nevada River Forecast Center reports that some areas in northern California have already accumulated up to five inches of rain in the past 24 hours. Flooding has already created dangerous situations for the residents of California.  

Readers can recreate the above animation and explore other GOES data using RealEarth, a free web-based visualization tool for satellite and other remote sensing weather products.

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GOES-17 — and GOES-18, beginning at 1801 UTC on 04 January (after GOES-18 became the operational GOES-West satellite) — Air Mass RGB images (above) showed a rapidly-intensifying Hurricane Force low pressure system (surface analyses) over the East Pacific Ocean as it approached the US West Coast during the 03 January – 04 January 2023 period (brief periods with horizontal striping in the earlier GOES-17 images was due to that satellite’s Loop Heat Pipe issue).  As the crude oil tanker POLAR RESOLUTION was moving south-southeastward along the western periphery of the storm, it reported winds as strong as 50-60 knots which were frequently producing blowing spray (1001 UTC Air Mass RGB image) — and Buoy 46006 reported wind gusts of 60 knots (2001 UTC Air Mass RGB image) and wave heights of 41 feet.

With abundant illumination from the Moon (which was in the Waxing Gibbous phase, at 95% of Full), a Suomi-NPP VIIRS Day/Night Band (0.7 µm) image at 1004 UTC (2:44 AM PST) on 04 January provided an excellent “visible image at night” of the storm. Note the POLAR RESOLUTION report of 55 knot winds with blowing spray (near the western edge of the storm’s cloud shield).

GOES-17/GOES-18 True Color RGB (and Nighttime Microphysics RGB) images from the CSPP GeoSphere site (below) displayed the cloud features within the storm’s broad circulation, in addition to a long/narrow cloud band associated with its trailing cold front (which eventually moved south of all the islands of Hawai`i, except the Big Island — as shown in the surface analysis at 0000 UTC on 05 January).

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