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

Low-Level Water Vapor Infrared imagery (7.34 µm) from GOES-16, above, shows Hurricane Harvey developing a distinct eye shortly after sunrise on 25 August 2017 after intermittent appearances of the eye during the night. Harvey is a strong Hurricane at 950 mb (as of 700 AM CDT according to the National Hurricane Center) and is approaching the central Gulf Coast of Texas. Strong upper-level outflow to the north and then east and south is apparent in the Water Vapor animation above, and an absence of dry air near the storm portends no significant weakening before the storm reaches the Coastline. Microwave estimates of Total Precipitable Water, below, from this site, continue to show extreme moisture amounts enveloping the storm.

Visible imagery, below, from after sunrise on 25 August 2017, show a symmetric storm with a visible eye. The “Cirrus Channel” near-infrared GOES-16 Channel (1.38), bottom, shows the extensive cirrus canopy from the storm covering much of the western Gulf of Mexico and adjacent states.

For the latest information on Harvey, consult the pages of the National Hurricane Center, or the CIMSS Tropical Weather Website. In addition to the flooding threat posed from Harveywith multiple days of rain, storm surge at the coast promises considerable inundation.

A toggle between Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 1853 UTC , below, provided a detailed view of the hurricane as it continued to near the Texas coast.

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

Overnight Satellite imagery from GOES-16, above, shows an increase in the size and convective activity with then-Tropical Storm Harvey. Harvey is forecast to make landfall on the Texas Gulf Coast (See the National Hurricane Center website for further details), and conditions favor strengthening. One of the favorable conditions is shown in the animation of Total Precipitable Water, below, from this site. There is abundant moisture surrounding the storm, extending into eastern and southeastern Texas. Flooding rains will likely precede and accompany this storm.

In addition to abundant moisture, Harvey’s projected path takes it over very deep very warm water (Link showing Oceanic Heat Content).

Note: Harvey achieved Hurricane Status at 1 PM CDT on 24 August 2017. Harvey continued to rapidly intensify during the day (ADT | SATCON).

Harvey is a large storm. The GOES-16 “Cirrus Channel” 1.38 µm imagery, below, shows Harvey’s cirrus canopy covering much of the southwestern Gulf of Mexico. Cirrus from the storm should be visible from the south Texas Gulf Coast this morning.

Suomi NPP overflew the southern Gulf after midnight on 24 August 2017, and the VIIRS  Day/Night Band Imagery, below, shows a few lightning streaks in the storm that is barely illuminated by airglow. Cloud-top heights computed from VIIRS data (Link) shows a large central dense overcast with heights exceeding 50000 feet. ATMS 88-GHz Imagery at the same time is shown here. Morphed Microwave imagery (from this site) hints at the development of a ragged eye shortly after sunrise on 24 August. (Animation). (A DMSP SSMI 85 GHz still image from near the end of the MIMIC animation is here).

ATMS 88-GHz Imagery at the same time is shown here. Morphed Microwave imagery (from this site) hints at the development of a ragged eye shortly after sunrise on 24 August. (Animation). An 85 GHz still image from the end of the animation is shown below.

Later in the day, a toggle between 1912 UTC Visible (0.64 µm) and Infrared Window (11.45 µm) Suomi NPP VIIRS images, below, provided a detailed view of the hurricane.

For more information on Hurricane Harvey, a storm that people along the Texas Gulf Coast should be monitoring closely, consult the website of the National Hurricane Center, or the CIMSS Tropical Weather Website.

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* 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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