1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed the eastward progression of a Mesoscale Convective System (MCS) that produced a long swath of damaging winds (SPC Storm Reports) or derecho from eastern Nebraska to Indiana on 10 August 2020. The highest measured wind gust was 112 mph in eastern Iowa at 1755 UTC.

The corresponding GOES-16 “Clean” Infrared Window (10.35 µm) images are shown below.

In a comparison of Infrared Window images from Suomi NPP (11.45 µm) and GOES-16 (10.35 µm) at 1931 UTC (below), the higher spatial resolution of the VIIRS instrument detected infrared brightness temperatures as cold as -84ºC, compared to -76ºC with GOES-16 (the same color enhancement is applied to both images). The northwest parallax offset associated with GOES-16 imagery at this location was also evident.

GOES-16 Visible/Infrared Sandwich Red-Green-Blue (RGB) and “Clean” Infrared Window (10.35 µm) images, with “probability of intense convection” contours and SPC Storm Reports, is shown below. The probability contours are produced from a deep-learning algorithm used to identify patterns in ABI and GLM imagery that correspond to intense convection. It is trained to highlight strong convection as humans would identify it. Work is ongoing to incorporate this storm-top information into NOAA/CIMSS ProbSevere.

A comparison of Terra MODIS True Color RGB images (source) from before (28 July) and after (11 August) the derecho (below) revealed very large swaths of wind-damaged crops (lighter shades of green) across Iowa. It is estimated that around 10 million acres of corn and soybean crops were flattened by the strong winds.

A toggle between VIIRS True Color RGB images from Suomi NPP and NOAA-20 visualized using RealEarth (below) also displayed the crop damage swath.

Shown below is a before/after (28 July/11 August) comparison of VIIRS Day/Night Band (DNB) imagery (source), where many of the areas across Iowa that suffered significant power outages — appearing darker (due to a lack of city lights) on the nighttime DNB images — corresponded to the large swaths of crop damage seen on the 11 August MODIS True Color image. Around 550,000 households lost power across the state.

Even 2 days later (on 12 August), many customers remained without power across Iowa (below), especially in Marshall County (where peak winds of 106 mph were recorded), Tama County (where peak winds of 90 mph were recorded) and Linn County (where peak winds of 112 mph were recorded).

Updated estimated wind speed map for the #derecho2020. #iawx #IowaDerecho pic.twitter.com/XMaAgc6oHT

— NWS Des Moines (@NWSDesMoines) August 20, 2020

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JMA Himawari-8 True Color Red-Green-Blue (RGB) images created using Geo2Grid (above) displayed the gray to tan hues of a narrow west-to-east oriented volcanic ash cloud following an eruption of Mount Sinabung on 10 August 2020.

A sequence of Terra MODIS False Color RGB, Ash Probability, Ash Loading, Ash Height and Ash Effective Radius products from the NOAA/CIMSS Volcanic Cloud Monitoring site (below) showed various characteristics of the ash plume at 0415 UTC.

A plot of 00 UTC rawinsonde data from Medan (below) helped to explain the different ash height and ash transport characteristics — the higher-altitude portion of the ash plume was transported westward by easterly flow above the 500 hPa (5.9 km) level, while the lower-altitude portion moved eastward due to westerly winds below 500 hPa.

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GOES-16 (GOES-East) True Color Red-Green-Blue (RGB) images created using Geo2Grid (above) showed widespread smoke from biomass burning across parts of Brazil (south of the Amazon River) on 09 August 2020. Most of this smoke was created by extensive burning during the previous day and evening — but later in the animation, several new smoke plumes can be seen growing from new fire activity.

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed clusters of thunderstorms that developed along and just behind a cold front moving eastward across Minnesota on 08 August 2020. The northernmost hail-producing thunderstorm in Minnesota exhibited an Above-Anvil Cirrus Plume (reference | VISIT training); in addition, a decaying thunderstorm complex in southeastern North Dakota eventually revealed the cyclonic circulation associated with a Mesoscale Convective Vortex.

GOES-16 Visible images (above) and Infrared images (below) included time-matched SPC Storm Reports.

A toggle between time-matched NOAA-20 VIIRS Infrared Window (11.45 µm) and GOES-16 “Clean” Infrared Window (10.35 µm) images (below) demonstrated the northwestward parallax displacement of GOES-16 cloud-top features (note: the same color enhancement enhancement has been applied to both images). Due to the 375-meter spatial resolution of VIIRS imagery, it was able to sense overshooting top infrared brightness temperatures as cold as -77.8ºC (compared to -65.7ºC with GOES-16). The higher resolution VIIRS image also provided a clearer depiction of the cloud-top gravity waves and tendrils of transverse banding.

A GOES-16 Infrared image with parallax displacement vectors and magnitudes (in km) from this site is shown below. For a 50,000 foot cloud top over southern Minnesota, the parallax adjustment was to the southeast at a distance of 21 km (13 miles) — this corresponded well to what was seen in the NOAA-20/GOES-16 comparison above.

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