Suomi NPP VIIRS Infrared Window (11.45 µm) images (above) revealed a large area of cold surface infrared brightness temperatures across much of the North Slope of Alaska on 04 February 2021 — with the coldest IR temperature being -56ºC (darker shades of violet) about 30 miles south-southeast of Umiat (PAUM)... Read More

Suomi 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... Read More

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... Read More

GOES-17 (GOES-West) Mid-level Water Vapor (6.9 µm) images (above) showed the circulation of an anomalous middle-tropospheric cutoff low over the northwestern portion of Alaska on 12 June 2020. A Potential Vorticity (PV) anomaly associated with this low was causing the dynamic tropopause — represented by the pressure of the PV1.5 surface —... Read More