VIIRS Infrared images from Suomi-NPP and NOAA-21 (above) showed widespread ice leads (brighter shades of cyan) in the Beaufort Sea during the 3-day period from 10-12 February 2026 — with a notable increase in ice leads across the eastern Beaufort Sea.

Surface wind stress was the primary influence affecting the motion and evolution of these ice leads. Surface analyses (below) showed that a tighter pressure gradient developed across the Beaufort Sea during the 3-day period — between high pressure centered over the Siberian Sea and broad cyclonic flow across the Bering Sea and interior/northern Alaska — which would have induced a stronger easterly flow across much of the VIIRS image domain displayed above.

Daily results using an AI-based sea ice lead detection method covering the entire Arctic Ocean are shown below; the Beaufort Sea is located within the bottom right portion of the images.

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EUMETSAT Meteosat-9 Infrared images (above) showed Cyclone Gezani as it made landfall along the east coast of Madagascar (near the city of Toamasina, station identifier FMMT) around 1645 UTC on 10 February 2026 — as a 110-kt Category 3 storm (JTWC discussion). Gezani had been rapidly intensifying on 10 February prior to landfall (ADT | SATCON). After landfall, the eye of Gezani quickly became cloud-filled as the storm interacted with the topography of the island. Gezani was responsible for at least 41 fatalities, and displaced more than 16000 residents.

A time series of surface data from Toamasina (below) depicted a wind gust of 73 kts at 1500 UTC — their final report before apparently abandoning the airport, or stronger winds subsequently causing power outages.

An ATMS Microwave image (below) displayed the eyewall of Gezani at 1034 UTC, about 1.5 hours prior to the storm reaching Category 3 intensity.

Meteosat-9 Infrared images with an analysis of deep-layer wind shear (below) indicated that Gezani was moving through an environment of very low shear — a factor that was favorable for the tropical cyclone reaching Category 3 intensity several hours prior to making landfall.

An analysis of Sea Surface Temperature (below) showed that Gezani had been traversing relatively warm water, with SST values of 28C.

ADT, SATCON, ATMS, Wind Shear and SST imagery were sourced from the CIMSS Tropical Cyclones site.

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While tropical beaches may be the first thing that comes to mind when thinking about Hawaii, it’s important to remember that the Big Island of Hawai’i has significant elevation. The highest point, Mauna Kea, is over 13,800 feet above sea level. Even though it’s the tropics, this is a high enough altitude that occasional snow can be seen during the winter months

Om 9 February 2026, conditions were ripe for a notable snowfall. Large levels of moisture coupled with an upper-level disturbance created an environment that could easily support snow at high elevations. Let’s start by looking at the moisture around Hawaii via the CIMSS MIMIC-TPW2 product. It’s clear that Hawaii lies right in the middle of the flow of an atmospheric river linking the continental United Staes to the Equator. With almost two inches of precipitable water available, the potential for a significant precipitation event is real.

Upper level support comes from an advancing trough, which can be seen in the 6.19 micron water vapor imagery from GOES-18 as the strong gradient in brightness temperatures and the general direction of flow from the southwest to the northeast. Thus, dynamic lifting is present in this very moist environment.

The Band 13 (infrared wind) imagery confirms the development of deep, moist convection. The tops of these clouds have brightness temperatures well below freezing, so snow is being formed here.

We can further confirm the cold nature of these clouds by looking at the day cloud phase distinction RGB, where the yellow clouds are indicative of thick, deep clouds in the ice phase.

We have said that it was moist. But how moist was it? The 1200 UTC sounding from Hilo (on the Big Island) can provide some insight here. This sounding was obtained from the University of Wyoming Radiosonde Archive and shows a deep layer of saturated air stretching from the surface to above the 400 mb level. The freezing level was at 640 mb (3900 m, or around 12,800 feet) and was well-below the maximum elevation of Mauna Kea.

The CIMSS Satellite blog, of course, is a strong proponent of using NUCAPS to help diagnose the thermodynamic conditions via satellite. However, this particular case exhibits some of the challenge of using satellite-based observations of temperature. The following image shows the gridded NUCAPS temperature at 700 mb. Note that the 700 mb temperature over the Big Island is right at freezing, and, givne that this is only 700 mb, the highest parts of the mountain would be well-below that critical temperature. However, the previous satellite images show that this is where the clouds are at their thickest, and precipitaiton is likely here. The colored dots representing profile quality are largely red, indicating that the NUCAPS retrieval results in this area are likely to be error-prone.

Given all of these conditions, the local weather service office issued a Winter Storm Warning for the high elevations of the Big Island. Such an event may be rare compared to the NWS offices in the upper midwest, but it’s not unheard of. Thanks to the fantastic archive at the Iowa Environmental Mesonet, it’s possible to track just how often a Winter Storm Warning is issued by a particular office. Some of these events have multiple warnings issued so it’s not trivial to connect the number of warnings to the number of significant snow events, but we can at least be sure that most years have at least one noteworthy snow event in Hawaii.

And, on a personal note, this post on Hawaiian weather is dedicated to NOAA NWS Honolulu meteorologist, native Hawaiian, and UW-Madison alumnus Will Ahue, who recently passed away. He was a friend to everyone he met, including those of us here at CIMSS. He will be deeply missed.

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As a low pressure system was located off the US East Coast on 07 February 2026, a so-called “Norlun Trough” (named after meteorologists Nogueira and Lundstedt) or “inverted trough” extended northwestward from the offshore low center to southern New England (above).

10 hours of 1-minute Mesoscale Domain Sector GOES-19 (GOES-East) Infrared images (below) showed the development of convective cloud bands (brighter shades of green) within the area of surface convergence in the vicinity of the Norlun trough. Surface convergence was also enhanced by an approaching arctic cold front (which eventually merged with the Norlun trough). These convective cloud bands helped to enhance snowfall rates.

5 hours of 1-minute GOES-19 Infrared images that included County outlines and County names (below) helped to identify the areas where the highest snowfall accumulations occurred (which as of 2002 UTC included 13.0″ in Essex County in far northeastern Massachusetts, 9.8″ in Washington County in far western Rhode Island and 8.0″ in Windham County in far eastern Connecticut).

A map of final Snowfall Totals on 07 February is shown below, depicting the highly-localized maxima across northeast Massachusetts, southeast Connecticut and southwest Rhode Island. These final snowfall totals included additional accumulation (after 20 UTC) from ocean effect snow.

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