* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing*

GOES-16 CONUS Sector images (at 5-minute intervals)

During the total solar eclipse of 21 August 2017, the lunar umbra was evident on imagery from the GOES-16 0.5 km resolution (at satellite sub-point) “Red” Visible band (0.64 µm) (above) and 1.0 km resolution Near-Infrared “Vegetation” band (0.86 µm) (below).

The shadow was also prominent in other Visible and Near-Infrared bands, as shown in a 4-panel comparison of GOES-16 “Blue” Visible (0.47 µm), “Red” Visible (0.64 µm), “Vegetation” (0.86 µm) and “Snow/Ice” (1.61 µm) images (below).

GOES-16 True Color Red-Green-Blue (RGB) images from the SSEC Geostationary Satellite site (below) showed another view of the shadow. A GOES-16 Full-Disk true-color animation (courtesy of  Kaba Bah, CIMSS) is available here; a composite of eclipse shadow images can be seen here.

The 3.9 µm Shortwave Infrared band is also sensitive to reflected solar radiation — particularly that which is reflected from land surfaces and cloud tops composed of small spherical supercooled water droplets (and to a lesser extent, small ice crystals) — which causes this band to sense warmer (darker gray to black) brightness temperatures compared to the other ABI infrared bands. Therefore, a loss of sunlight within the eclipse shadow will lead to cooling (lighter shades of gray) 3.9 µm brightness temperatures (below).

Taking a closer look at eastern Missouri and southern Illinois as the solar eclipse shadow was passing over that region shortly after 1800 UTC (1:00 pm local time), GOES-16 “Red” Visible (0.64 µm) images (below) revealed that the pronounced decrease of incoming solar radiation appeared to temporarily suppress the development of widespread boundary layer cumulus clouds. Note that the increase in hourly surface temperatures was also halted, with some locations even experiencing a slight cooling (1-3 ºF) due to reduction of solar heating within the lunar umbra.

GOES-16 Shortwave Infrared (3.9 µm) images (below) also showed a slight cooling — seen as a lighter shade of red enhancement — across the region.

GOES-16 Mesoscale Sector images (at 1-minute intervals)

A “floating” Mesoscale Sector provided 1-minute imagery during the eclipse (above).

Polar-orbiting satellite images (Terra MODIS, and Suomi-NPP VIIRS)

A toggle between Terra MODIS Visible (0.65 µm), Land Surface Temperature product, Shortwave Infrared (3.7 µm) and Infrared Window (11.0 µm) images (above) showed the eclipse shadow as it was centered over western Nebraska around 1748 UTC. Without a time series of MODIS Land Surface Temperature product images, it is difficult to gauge the exact amount of surface cooling brought about within the shadow of totality. A large-scale high resolution Terra MODIS Visible image is available here (courtesy of Liam Gumley, SSEC).

A comparison of Suomi-NPP VIIRS Visible (0.64 µm), Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images (above) showed the shadow center over eastern Tennessee around 1833 UTC. A closer comparison of Day/Night Band and Infrared images (below) revealed the presence of cloud features that made it difficult to see a signature of any city lights that may have come on in the Nashville TN (KBNA) metropolitan area.

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* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing *

Filaments of smoke aloft from Canadian wildfires were evident in GOES-16 “Red” Visible (0.64 µm) and Cirrus (1.37 µm) imagery (above; also available as a 24 Mbyte animated GIF) on 17 August 2017, drifting cyclonically eastward over Quebec, Maine and the Canadian Maritimes. The appearance of the smoke signature on Cirrus images was due to the fact that this spectral band is useful for detecting features composed of particles that are efficient scatterers of light (such as cirrus cloud ice crystals, airborne dust or volcanic ash, and in this case, smoke).

A comparison of GOES-16 “Clean” Infrared Window (10.3 µm) and Cirrus (1.37 µm) images (below; also available as a 21 Mbyte animated GIF) demonstrated that no smoke signature was seen on the infrared images (since smoke is effectively transparent at infrared wavelengths).

A more upstream view of the smoke feature was provided by a comparison of  Terra MODIS Visible (0.65 µm), Cirrus (1.375 µm) and Infrared Window (11.0 µm) images at 1626 UTC (below). Again, note the lack of a smoke signature in the Infrared image.

Depending on the altitude of these smoke filament features, daily composites of  Suomi NPP VIIRS true-color images covering the 5-day period of 12 August – 17 August (below) suggest that their source was either widespread fires in the Northwest Territories, or intense fires in British Columbia (which included pyroCb that injected smoke to very high altitudes).

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GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing

Hurricane Gert, a Category-1 storm on the Saffir-Simpson scale, is over the open Atlantic Ocean east of Cape Hatteras. It is close enough to the USA, however, that it is within GOES-16’s CONUS domain where 5-minute sampling is routine. The animation above shows all 16 channels from GOES-16 ABI, every five minutes from 1912-2132 UTC on 15 August 2017. A distinct eye is not apparent in the visible or infrared satellite imagery, but microwave data (from here) suggests an eye is present, at least at times. A comparison of 2035 UTC DMSP-16 SSMIS Microwave (85 GHz) and 2045 UTC GOES-13 Infrared Window (10.7 µm) images can be seen here.

The low-level Water Vapor imagery, below, shows that Gert is south and east of a front along the East Coast. This front should steer the storm to the north and east. Swells from the storm will affect the East Coast however.

For more information on Gert, consult the website of the National Hurricane Center, or the CIMSS Tropical Weather Website.

GOES-16 ABI Imagery from the morning of 16 August 2017, below, shows that an eye has appeared in visible and infrared imagery.

A closer view using 1-minute interval GOES-16 Mesoscale Sector “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images, below, showed that  the most vigorous areas of deep convection were generally confined to the northern semicircle of the eyewall region — cloud-top infrared brightness temperatures were as cold as -80º C (violet color enhancement) at times.

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The paths that Polar Orbiting satellites take around the Earth are predictable, and the prediction for next Monday, 21 August 2017 is shown above (image courtesy Rick Kohrs, SSEC). Note that Suomi NPP has an ascending orbit passing over the eastern part of the USA, from Florida to Michigan, at predicted times of 1830-1834 UTC on 21 August 2017. At 1832 UTC, Suomi NPP should be over the Great Smoky Mountains.

At the same time, the shadow of totality will be over eastern Tennessee as well, as shown below (from this site). Thus, Suomi NPP will be well-positioned to observe a snapshot (with excellent spatial resolution) of the umbral shadow of this eclipse, to complement the excellent temporal resolution of GOES-16.

Note: GOES-16 also observed the shadow of the 26 February 2017 solar eclipse in the Southern Hemisphere. In addition, the Advanced Himawari Imager (AHI) on Himawari-8 viewed the shadow of the Eclipse in the western Pacific Ocean on 9 March 2016 (Click here for an mp4 animation of all 16 AHI Channels).

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