The corresponding GOES-17 “Clean” Infrared Window (10.35 µm) images (below) also showed the large area of cold surface IR brightness temperatures, but the temperatures were not as cold (in the -40 to -50ºC range), and the small-scale signatures of various topographical features were not depicted.
A toggle between Infrared Window images from Suomi NPP VIIRS and GOES-17 (10.35 µm) at 1223 UTC is shown below.Cold temperatures across the North Slope of Alaska
February 4th, 2021 | Scott BachmeierIce leads in the Beaufort Sea
December 20th, 2020 | Scott BachmeierSuomi NPP VIIRS Infrared Window (11.45 µm) images (above) showed widespread ice leads in the Beaufort Sea during the 18 December – 20 December 2020 period. Some existing leads increased in width and/or length as they migrated westward, while some new leads were seen to form as land-fast ice fractured off the coasts of Alaska and larger islands of the Canadian Arctic Archipelago.
Suomi NPP VIIRS Infrared images with plots of NAM12 model surface winds on 20 December (below) indicated that the ice lead motion was influenced by surface wind stress — which also played a role in the clockwise flow of the Beaufort Gyre (the primary influence of ice lead motion in that part of the Arctic Ocean).
![Suomi NPP VIIRS Infrared Window (11.45 µm) images, with plots of NM12 model surface winds [click to enlarge]](https://cimss.ssec.wisc.edu/satellite-blog/images/2020/12/201220_suomiNPP_viirs_infrared_nam12winds_Beaufort_Sea_ice_leads_anim.gif)
Suomi NPP VIIRS Infrared Window (11.45 µm) images, with plots of NAM12 model surface winds [click to enlarge]
CIMSS Scientists are working on a Machine-learning Ice Lead detection method, as described here. The toggle below compares the MODIS and VIIRS computations of Ice Leads on 18 December 2020. Leads in this toggle are white; greys are suspected leads, but the detection algorithm ultimately could not confirm their presence. At present, the algorithm is challenged when leads are moving, as in this example. Note that Banks Island, on the right edge of the animation above, is in the lower left corner in the toggle below.
GOES-17 IFR Probability fields are now being created for Alaska
October 15th, 2020 | Scott Lindstrom
GOES-17 IFR Probability fields over Anchorage AK and surroundings, 0200 – 1300 UTC on 15 October 2020 (Click to animate)
CIMSS is now producing IFR Probability fields (and Low IFR Probability, Marginal VFR Probability, and Cloud Thickness fields) using GOES-17 data. (Recall that GOES-16 IFR Probability fields are now produced by NOAA/NESDIS and are distributed via the Satellite Broadcast Network (SBN) to National Weather Service Forecast Offices. GOES-16, however, does not view Alaska). GOES-17 fields will presently be available via an LDM pull. NOAA/NESDIS will likely start processing the fields in 2021.
The animation above shows IFR Probability fields today over the Anchorage region. The animation is preceded by a view of the topographic features, and IFR conditions on 15 October seem centered on topographic features.
GOES-17 can view the North Slope of Alaska. This location is quite far from the GOES-17 sub-satellite point, so resolution is degraded from the nadir 2-km views. However, regions of likely IFR conditions are easily tracked (Again, the animation is preceded by topography), with a large region between the Arctic Ocean and the high terrain of the Brooks Range.

GOES-17 IFR Probability fields over northern Alaska, 0200 -1300 UTC, 15 October 2020 (Click to animate)
GOES-17 views of Alaska southeast, below show probabilities of low clouds and reduced visibility. As over other regions of Alaska today, highest probabilities are over high terrain. GOES-17 IFR Probability for the PACUS domain is available at this website. Work is ongoing to insert IFR Probability (from GOES-16 and GOES-17) into Real Earth.

GOES-17 IFR Probability fields over Alaska Southeast, 0200 -1400 UTC, 15 October 2020 (Click to animate)
GOES-17 fields contain artifacts in the form of horizontal stripes that can be traced to the poorly-functioning Loop Heat Pipe on GOES-17. GOES-17 is now in a reduced-scanning mode between 0600 and 1200 UTC to enhance the ability of the satellite to shed excess heat: fewer Mesoscale sectors are scanned, full disk sectors are not as frequent (every 15 minutes instead of every 10), and the ‘PACUS’ sector is not scanned. This scanning strategy will continue through the end of October.
The Forecast Decision Training Division has a Quick Guide on IFR Probability fields here. A 20-minute YouTube video explaining the product is here.
Cutoff low over northern Alaska
June 12th, 2020 | Scott Bachmeier![GOES-17 Mid-level Water Vapor (6.9 µm) images, with contours of PV1.5 Pressure plotted in red [click to play animation | MP4]](https://cimss.ssec.wisc.edu/satellite-blog/images/2020/06/ak_wv-20200612_210032.png)
GOES-17 Mid-level Water Vapor (6.9 µm) images, with contours of PV1.5 Pressure plotted in red [click to play animation | MP4]
![GOES-17 Mid-level Water Vapor (6.9 µm) images, with contours of PV1.5 Pressure plotted in red and available NUCAPS sounding profiles denoted by green/yellow points [click to enlarge]](https://cimss.ssec.wisc.edu/satellite-blog/images/2020/06/ak_wv_nucaps-20200612_215031.png)
GOES-17 Mid-level Water Vapor (6.9 µm) images, with contours of PV1.5 Pressure plotted in red and available NUCAPS sounding profiles denoted by green/yellow points [click to enlarge]
![GOES-17 "Red" Visible (0.64 µm) images, with hourly surface reports plotted in red [click to play animation | MP4]](https://cimss.ssec.wisc.edu/satellite-blog/images/2020/06/ak_vis-20200612_210032.png)
GOES-17 “Red” Visible (0.64 µm) images, with hourly surface reports plotted in red [click to play animation | MP4]
![VIIRS True Color (RGB) and Infrared Window (11.45 µm) images from NOAA-20 and Suomi NPP [click to enlarge]](https://cimss.ssec.wisc.edu/satellite-blog/images/2020/06/200612_noaa20_suomiNPP_trueColorRGB_infraredWindow_AK_anim.gif)
VIIRS True Color (RGB) and Infrared Window (11.45 µm) images from NOAA-20 and Suomi NPP [click to enlarge]
Summer thunderstorms stretched across the North Slope and near the Arctic Coast today. Data from the GLD360 depicted over 800 Cloud-to-Ground lightning events in the area! Here is the scene at Atqasuk, Utqiagvik, Nuiqsut, and Deadhorse this afternoon and evening. #akwx #lightning pic.twitter.com/tGeqswONW5
— NWS Fairbanks (@NWSFairbanks) June 13, 2020