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

East Pacific Ocean Tropical Depression 1E intensified to become Tropical Storm Adrian (at 9.5º N latitude, 92.3º W longitude) at 03 UTC on 10 May 2017 — making it the earliest tropical storm on record in the East Pacific basin during the meteorological satellite era. GOES-16 Infrared Window (10.3 µm) images (above) revealed a series of nocturnal convective bursts which exhibited cloud-top infrared brightness temperatures in the -80º to -89º C range (shades of violet color enhancement).

During the subsequent daylight hours, GOES-16 Visible (0.64 µm) images (below) showed that southeasterly deep layer wind shear (source) had decoupled the organized convection from the exposed low-level circulation center (LLCC). Due to the far southern location of Adrian, only Full Disk scan images were available, at 15-minute intervals.

However, one of the GOES-16 Mesoscale Sectors was positioned over Adrian during the 2226-2355 UTC period, providing images of the LLCC at 1-minute intervals (below).

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

Severe thunderstorms developed over eastern Colorado on 08 May 2017, producing large hail (especially in the Denver area: SPC storm reports | NWS Boulder summary). Both GOES-16 Mesoscale Sectors were positioned over that region, providing 30-second interval images — Visible (0.64 µm) and Infrared Window (10.35 µm) images (above) showed the convection in great detail, with SPC storm reports of hail size (inches; H275 = 2.75 inches in diameter) plotted in red/cyan. Several of the storms exhibited well-defined overshooting tops in the Visible imagery, as well as “enhanced-V” and/or cold-warm “thermal couplet” signatures on the Infrared imagery.

#GOES16 30-sec visible texture (blue (red) lines, weak (strong) overshooting) and IR cold spot (magenta) detects strong CO storms on 8 May pic.twitter.com/ApGrC0NLNH

— Kris Bedka (@krisbedka) May 11, 2017

A comparison of 30-second interval GOES-16 Mesoscale Sector and 15-minute interval GOES-13 (GOES-East) Routine Scan visible images (below) demonstrated the clear advantage of rapid-scan imagery for monitoring convective development. Also note the degradation of GOES-13 visible imagery (the cloud features do not appear as bright), due to the age of that satellite — the GOES-R series ABI instrument features on-board visible detector calibration, so this type of visible image degradation over time will not occur.

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images (below; actual satellite overpass time 1943 UTC) provided a high-resolution (375 meter) view of the developing thunderstorms, about 17 minutes before the first report of hail northeast of Trinidad (KTAD) at 2000 UTC — a number of these storms exhibited cloud-top infrared brightness temperatures of -70 to -73º C (black enhancement). The VIIRS instrument will also be on the JPSS series of satellites, the first of which is scheduled to be launched in the 4th quarter of 2017.

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Cyclone Donna (18P) formed in the South Pacific Ocean (northeast of Vanuatu) on 02 May 2017. Himawari-8 Infrared Window (10.4 µm) images during the 03-06 May period (above) revealed the formation of multiple convective bursts, many exhibiting cloud-top IR brightness temperatures of -90º C and colder.

On 07 May, Cyclone Donna rapidly intensified from a Category 2 to a Category 4 storm (SATCON | ADT) — and Himawari-8 Infrared Window images (below) showed the presence of a large eye for a few hours. Environmental factors favoring rapid intensification included warm sea surface temperatures and light vertical wind shear.

A comparison of GMI Microwave (85 GHz) and Himawari-8 Infrared Window (10.4 µm) images from the CIMSS Tropical Cyclones site (below) showed that the actual diameter of the eye was much larger on microwave imagery around 1400 UTC on 07 May.

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

One of the two GOES-16 Mesoscale Sectors was moved from its default position over the eastern United States and placed over the west coast of the United States on 4 May 2017. This allowed 1-minute imagery of a small-scale coastal eddy between Cape Mendocino and Pt. St. George near Crescent City, above, and an associated coastal jet. (Click here to play 300-meg Animated Gif; alternatively, this animation shows the eddy from 1600-1900 UTC as displayed in AWIPS (courtesy Dan Miller, WFO DLH))

A zoomed-in Visible animation of the coastal eddy is shown below; NWS Eureka described it as “one of the best examples of these coastal eddies seen in quite a while”.

GOES-16 Visible 0.64 µm imagery is able to capture not only the eddy, but also the northerly low-level jet that develops off the coast of Cape Mendocino, swiftly moving clouds southward around that feature. A small eddy also develops south of Cape Mendocino. Note also the abundance of cirrus clouds flowing northward along the coast.

The dimensions of this eddy are approximately 70 km in the along-shore direction and 55 km perpendicular to the shore, yet GOES-16 is able to capture and resolve many small-scale cloud bands. The small cloud band streaming south around Cape Mendocino, for example, is only about 6 km wide and is well-resolved; if GOES-16 becomes GOES-East at 75 W Longitude, this is the type of resolution that can be expected in Salt Lake City.

It should be noted that none of the models (including the hourly RTMA, below) resolved this eddy feature.

Thanks to Dan Miller, Science and Operations Officer (SOO) in Duluth for calling this awesome feature to our attention!

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