A Nebraska thunderstorm and a Wyoming wildfire, as viewed by GOES-15, GOES-17 and GOES-16

August 29th, 2018 |
Visible images from GOES-15 (0.63 µm, left), GOES-17 (0.64 µm, center) and GOES-16 (0.64 µm, right), with SPC storm reports plotted in red [click to play animation | MP4]

Visible images from GOES-15 (0.63 µm, left), GOES-17 (0.64 µm, center) and GOES-16 (0.64 µm, right), with SPC storm reports plotted in red [click to play animation | MP4]

* GOES-17 images shown here are preliminary and non-operational *

A comparison of Visible images from GOES-15 (GOES-West), GOES-17 and GOES-16 (GOES-East) (above) showed an isolated thunderstorm that developed in the Nebraska Panhandle late in the day on 29 August 2018. The storm produced hail (SPC storm reports), and also exhibited an Above Anvil Cirrus Plume. The images are displayed in the native projection of each satellite, with no re-mapping.

One other feature that was seen north of the thunderstorm was smoke which was being transported eastward from the Britania Mountain Fire in southeastern Wyoming. The smoke was more apparent on the GOES-17 and GOES-16 images as forward scattering increased toward sunset.

Shortwave Infrared imagery from the 3 satellites revealed important differences affecting fire detection: namely spatial resolution and viewing angle. The 3.9 µm detector on the GOES-15 Imager has a spatial resolution of 4 km (at satellite sub-point), compared to 2 km for the GOES-16/17 ABI. Given that the fire was burning in rugged mountain terrain, the view angle from each satellite had an impact on the resulting bire brightness temperature values. For example, the first indication of very hot (red-enhanced) pixels was at 1527 UTC from GOES-16/17, vs 1715 UTC from GOES-15; at the end of the day, the very hot fire pixels were no longer seen with GOES-15 after 2300 UTC, but continued to show up in GOES-17 imagery until 0042 UTC and in GOES-16 imagery until 0122 UTC.

Shortwave Infrared images from GOES-15 (3.9 µm, left), GOES-17 (3.9 µm, center) and GOES-16 (3.9 µm, right) [click to play animation | MP4]

Shortwave Infrared images from GOES-15 (3.9 µm, left), GOES-17 (3.9 µm, center) and GOES-16 (3.9 µm, right) [click to play animation | MP4]

Stereoscopic Views of Convection every minute in Mesoscale Domains

August 29th, 2018 |

GOES-17 and GOES-16 Mesoscale Domains at 1616 UTC on 29 August 2018 (Click to enlarge)

GOES-17 images shown here are preliminary and non-operational

The presence of GOES-17 data means that 4 mesoscale sectors, each taking 1-minute imagery, are over the United States. In the example above, from 1616 UTC on 29 August 2018, there is no overlap. (Note: Three of the Four are in their default locations; the Mesoscale sector over the northeast United States has been shifted north to monitor convection over New England).

On 28 August 2018, however, two mesoscale sectors overlapped over the central United States, and sampled convection developing over Oklahoma (that subsequently caused wind damage in Roger Mills County in western Oklahoma). The Stereoscopic View of that convection is shown below. To view the convection in three dimensions, cross your eyes until you see 3 images, and focus on the image in the center. An animated gif (215 Megabytes!!) is available here.

GOES-16 (Left) and GOES-17 (right) Visible (0.64) stereoscopic views of convection developing over western Oklahoma, 2000 UTC 28 August – 0118 UTC 29 August 2018 (Click image to play mp4 animation)