5-minute CONUS Sector GOES-19 (GOES-East) Water Vapor and Infrared images (above) showed the development of a standing wave cloud over northeast Minnesota and Lake Superior on 19 January 2026. This cloud feature was formed by a vertically-propagating internal gravity wave that resulted from the interaction of post-frontal northwesterly surface winds with the topography of the shoreline — the terrain quickly drops from an elevation of about 2000 feet above sea level (over northeastern Minnesota) to about 600 feet above sea level (over Lake Superior) in a very short distance.

The coldest cloud-top infrared brightness temperature associated with this standing wave cloud was -53ºC — which roughly corresponded to the tropopause (at an elevation of 6.9 km), as depicted in 1200 UTC rawinsonde data at International Falls (below).

Similar standing wave clouds have been documented here on the blog, on 19 January 2022 and 08 January 2019.

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Strong northerly winds created blowing snow and blizzard conditions across parts of eastern North Dakota and western Minnesota — particularly within the Red River Valley — on 17 January 2026. 5-minute CONUS Sector GOES-19 (GOES-East) Near-Infrared “Snow/Ice” images (above) showed the development of Horizontal Convective Rolls (HCRs) where winds were channeled down the Red River Valley (topography) — with gusts in excess of 30 knots, reducing the surface visibility to less than 1 mile due to blowing snow at several METAR sites.

GOES-19 Blowing Snow RGB images created using Geo2Grid (below) provided a more distinct view of the HCRs.

===== 18 January Update =====

Even stronger winds in the wake of a cold frontal passage (with gusts in excess of 40 knots) produced a second day of blowing snow and blizzard conditions across eastern North Dakota and western Minnesota on 18 January — and HCRs were once again very prevalent in GOES-19 Blowing Snow RGB images (above), across a larger area than the previous day. The surface visibility was reduced to near zero at some METAR sites.

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Much of the state of Alaska is finds itself impacted by a strong atmospheric river on Friday, 16 January 2026. Moisture has been plunging due north from the tropics to the southern coast of Alaska. The river has brought with it precipitation and temperatures well above normal. One of the best ways to monitor the location and strength of an atmospheric river is with the CIMSS MIMIC-TPW product, which merges polar-orbiting and geostationary products to provide microwave-like observations of total precipitable water at a much greater frequency than is possible with the polar orbiter microwave instruments. A quick glance at the MIMIC-TPW product makes it easy to identify the area of anomalous moisture.

Zooming out enables us to see the plume in a global context. Here, it appears as a direct plume linking Alaska directly to the high moisture region of the tropical Pacific. Note that this also appears to be not the only atmospheric river that is impacting Alaska, with another plume in the north central Pacific. According to the GFS model, these two rivers are forecasted to merge over the weekend.

The impacts of this river on sensible weather are significant. Temperatures in southern Alaska are elevated compared to normal. The normal high temperature for Anchorage on January 16 is 22 F, but temperatures reached 39 F by midday. Reports from Anchorage note rain falling on snow-packed roads, creating slippery conditions despite the greater-than-freezing temperatures. Numerous avalanche warnings have also been issued in southern Alaska due to large areas of heavy rain and snow created by the atmospheric river.

The GOES-18 water vapor channels (in this case, channel 8, 6.2 microns) can also provide some insight into the strength of this event. Here, it is easy to see how the moist air is streaming north to the southern Alaska shore where it then starts dispersing into the interior of Alaska as well as the Yukon and Northwest Territories of Canada. This loop also shows the challenges associated with using geostationary imagery in polar regions: the significant displacement from the sub-satellite point over the equator means oblique viewing angles and very coarse pixel resolution; just compare the size of the pixels at the top of this loop to those at the bottom.

At these higher latitudes, polar orbiting satellites offer a promising alternative. The primary disadvantage of polar orbiters, the relatively coarse temporal resolution relative to geostationary satellites, is lessened near the poles as orbits are constantly overlapping. However, neither the United States’s VIIRS nor EUMETSAT’s AVHRR have water vapor sensitive channels, so while views of the clouds from visible or infrared imagery are possible, additional information about the water vapor distribution at the fine horizontal resolution of a polar orbiting satellite is not possible.

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5-minute CONUS Sector GOES-19 (GOES-East) GeoColor RGB images with an overlay of Next Generation Fire System (NGFS) Fire Detection polygons (above) displayed numerous thermal signatures and smoke plumes associated with prescribed burns near the Gulf Coast of Texas and Louisiana on 15 January 2026.

Two of the hottest-burning fires occurred near the coast in far southwest Louisiana — as seen in a closer view (below).

The hottest of these 2 fires was located along the eastern shore of Sabine Lake (below) — which exhibited a maximum 3.9 µm brightness temperature of 136ºC (which is only about 2 degrees below the 137.77ºC saturation temperature of GOES-19 Band 7 detectors) at 1836 UTC. Interestingly, even though this was the hottest-burning fire (that produced a sizable and dense smoke plume) it only burned for about 4 hours, from 1726-2121 UTC.

The second fire was located farther east, in the Rockefeller Wildlife Refuge (below) — which exhibited a maximum 3.9 µm brightness temperature of 116ºC at 2051 UTC.

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