A sequence of three GOES-16 Near-Infrared “Snow/Ice” (1.61 µm), Near-Infrared “Cloud Particle Size” (2.24 µm) and Shortwave Infrared (3.9 µm) images with 1-minute plots of GLM Events (above) showed the brief signature of a meteor over the Florida Panhandle during the 0353-0354 UTC time period on 31 March, or 11:53-11:54 PM Eastern Daylight Time on 30 March 2019. The bright meteor signature was captured over northern Taylor County, northwest of the Perry-Foley Airport (station identifier K40J) — the GLM Events are plotted at their approximate location on the Earth’s surface (using the default GLM parallax correction).

The GOES-16 ABI instrument was scanning that portion of the Florida Panhandle at 03:52:54 UTC, slightly earlier than the time that the fireball flash was sensed by the GLM instrument, so no corresponding thermal signature was evident in the infrared imagery.

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A toggle between 30-meter resolution Landsat-8 False Color Red-Green-Blue (RGB) images viewed using RealEarth (above) revealed a large ice lead that had opened up to the east of Utqiagvik (Barrow), Alaska on 28 March 2019. Snow and ice appear as darker shades of cyan in the RGB image, with open water exhibiting a dark blue to black appearance.

A sequence of True Color RGB images from NOAA-20 / Suomi NPP VIIRS and Terra MODIS (below) showed the ice lead becoming wider with time during a 5-hour period (note: the time stamps on the images do not reflect the actual time each satellite passed over the Utqiagvik area). The MODIS image appeared the sharpest, since that instrument has a 250-meter resolution in the visible spectral bands (compared to 375 meters for VIIRS).

In a 14-day series of Terra MODIS composites (below) it can be seen that the same general ice fracture line had opened and closed a few times during the 15-28 March period, depending on the influences of surface wind stress and sea currents. Days with strong and persistent southwesterly winds led to an opening of the ice lead (such as 20 March); however, the largest 1-day change — and the largest opening of the ice lead — occurred from 27-28 March (MODIS | VIIRS), when the strong southwest winds were bringing unseasonably warm air (over 30ºF above normal) across the area. The daily high temperature at Utqiagvik on 28 March was 30ºF, which set a new record high for the date (the normal high temperature for 28 March is -3ºF). Incidentally, this period of above-normal temperatures contributed to Utqiagvik having its warmest March on record.

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Composites of Infrared imagery (above) and Water Vapor imagery (below) from the AMRC site showed an anomalously strong (MSLP | 925 hPa winds | source) cyclone that was moving southeastward across the South Pacific Ocean toward the coast of Antarctica on 26 March 2019. These composites blend images from both geostationary and polar orbiting satellites; the storm is located in the upper right quadrant of the images. On the Infrared imagery, brighter white shades over much of the middle of Antarctica indicated a very cold surface — in fact, surface air temperatures were as cold as -84ºF over the interior of the continent at 23 UTC.

The storm was evident along the southern limb of GOES-16 Full Disk scans, as seen on Mid-level Water Vapor (6.9 µm) and “Red” Visible (0.64 µm) images (below). The location of AMRC AWS station 8930 (Thurston Island) near the coast of Ellsworth Land in West Antarctica is indicated in red.

This storm was also evident at the bottom center of a GOES-17 + GOES-16 composite of north-to-south True Color Red-Green-Blue (RGB) swaths of 15-minute illumination at local solar noon — beginning at 12 UTC in the east, and ending at 03 UTC in the west — combined and displayed in a Mollweide projection (below; courtesy of Rick Kohrs, SSEC).

A time series of surface observation data from AWS station 8930 on Thurston Island (below) showed that southeasterly winds peaked at 113 knots (58 m/s) late in the day on 26 March as the strong low pressure system approached. According to AMRC staff, this particular AWS is located on a nunatak near Parker Peak in the Walker Mountains (map) — such an exposure is prone to periods of strong winds, requiring a recent retrofitting of special instrumentation designed to withstand and measure higher wind speeds.

A closer look with GOES-16 Visible and Low-level Water Vapor (7.3 µm) images (below) revealed small wave perturbations in the cloud field and the eventual formation of a banner cloud as Peter I Island was acting as an obstacle to the strong boundary layer winds south of the storm center.

A timely overpass of the Landsat-8 satellite provided a 30-meter resolution Landsat-8 False Color RGB image, viewed using RealEarth (below), of these orographically-induced cloud perturbations.

The orographic wave clouds downwind of Peter I Island could also be seen on 375-meter resolution Suomi NPP VIIRS True Color RGB and Infrared Window (11.45 µm) images at 19 UTC and 21 UTC (below).

#GOESWest is watching a hurricane-force low that’s headed toward the Antarctic Peninsula. This loop uses what’s known as Air Mass RGB Imagery, which helps distinguish polar from tropical air masses. More imagery: https://t.co/3SWkPqjxr9 pic.twitter.com/nUOKrYtfm1

— NOAA Satellites (@NOAASatellites) March 26, 2019

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GOES-17 (GOES-West) “Red” Visible (0.64 µm) and Low-level Water Vapor (7.3 µm) images (above) showed a northeasterly flow (model analyses) off the coast of British Columbia, Canada on 25 March 2019. Contained within this offshore flow was a hazy plume moving over Haida Gwaii and out across the eastern Pacific Ocean.

This aerosol plume was more easily seen in GOES-17 True Color Red-Green-Blue (RGB) images from the AOS site (below).

In comparisons between VIIRS Visible (0.64 µm) and Day/Night Band (0.7 µm) from Suomi NPP at 2104 UTC and NOAA-20 at 2154 UTC (below), the portion of the plume where aerosols were most dense (and therefore more reflective) was better portrayed in the Day/Night Band images.

Similarly, the portion of this plume having a higher aerosol concentration was highlighted using Terra MODIS Near-Infrared “Cirrus” (1.61 µm) imagery (below). The corresponding MODIS Water Vapor (6.7 µm) image showed that while the plume was generally contained within a ribbon of drier air, a narrow tongue of moisture existed within the core of the band of dry air. Both the VIIRS and the MODIS imagery indicated that the plume was passing over Sandspit (surface identifier CYZP), where the surface visibility briefly dropped to 7 miles at 21 UTC during a short period of northwesterly winds.

A toggle between the 2015 UTC Suomi NPP VIIRS True Color RGB image and Aerosol Optical Depth product as viewed using RealEarth (below) also showed the plume was passing over station CYZP on Haida Gwaii. Note that there were a few VIIRS fire detection points (red dots) in central British Columbia — which suggests that this aerosol plume was likely smoke from biomass burning.

Regarding the moisture gradient seen on the MODIS Water Vapor image, it is interesting to examine 3 adjacent closely-spaced NUCAPS soundings immediately south of CYZP (below). The Total Precipitable Water values increased from 0.18″ to 0.26″ within a distance of only 60 miles.

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