Four weeks of GOES-16 Full-Disk imagery, spanning 28 February to 24 March at a 15-minute interval, showing four Nor’easters, are available via the image above at YouTube.  The imagery shows CIMSS Natural Color during the day and a blend of GOES-16 ABI Shortwave (3.9 µm) and Longwave (10.3 µm) Infrared imagery at night.

The original mp4 (200 megabytes) is available for download here.

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GOES-16 (GOES-East) “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above) showed smoke plumes and fire “hot spots” associated with numerous wildfires burning in northeastern Oklahoma on 24 March 2018.

A comparison of Terra/Aqua MODIS and Suomi NPP VIIRS Shortwave Infrared images (below) showed  higher-resolution view of the fire hot spots.

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Dan Miller, the Science and Operations Officer (SOO) in Duluth sent the imagery above. Constant icebreaking has been ongoing on Whitefish Bay prior to the opening of the SOO Locks this weekend. A faint black line representing open water is apparent in the 22 March imagery, and it’s even more apparent in the 23 March imagery.

A toggle below, from 24 March 2018, shows the Band 2 “Red” (0.64 µm) Visible and the Band 5 “Snow/Ice” (1.61 µm) Near-Infrared images. The open water is apparent in both images — dark in contrast to the white snow and lake ice in the visible, darker than the adjacent ice in the 1.61 µm. Recall that horizontal resolution in Band 2 is 0.5 km at the sub-satellite point (nadir), and in Band 5 it is 1 km.

Suomi NPP and NOAA-20 also viewed the icebroken path on 24 March, and favorable orbit geometry for NOAA-20 and Suomi NPP on 24 March (orbit paths from this site) meant 2 sequential passes from both satellites both viewed Whitefish Bay. The 4 images are shown in an animation below, with imagery from NOAA-20 first, then Suomi NPP (the labels all say Suomi NPP erroneously). Note that NOAA-20 data are provisional, non-operational, and undergoing testing still).

The break in the ice was also visible in Day Night Band Imagery from VIIRS at 0722 UTC (from NOAA-20) on 24 March 2018.  It is also apparent in the shortwave Infrared imagery from both GOES-16 (very subtly) and from VIIRS (which offers better spatial resolution).

The icebreaking track was also apparent on 250-meter resolution Terra MODIS True-color and False-color Red-Green-Blue (RGB) images from the MODIS Today site (below). In the False-color image, ice and snow (in areas of sparse vegetation) show up as shades of cyan.

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The Storm Prediction Center issued an Extreme Fire Weather advisory for 23 March 2018, and a GOES-16 Mesoscale Sector (#2, from this site) was positioned over the High Plains of Texas to monitor.

The GOES-16 Shortwave Infrared imagery, above, from 1905-2058 UTC on 23 March 2018 shows rapid warming of pixels near Borger TX (KBGD), and then southeast of Borger and northeast of Amarillo (KAMA). Surface observations show gusty southwest winds and low dewpoints, ideal for fire. Under the cirrus shield to the south, decreased solar insolation meant less vertical mixing of dry air and high winds, so dewpoints were higher and winds were weaker, lessening the fire danger.

Note that missing pixels are apparent in the GOES-16 Shortwave IR imagery around 2010 UTC. Quality flags that highlight the extreme warmth of the pixel have been activated, and AWIPS data are reported as missing in those locations.

Visible imagery, both Band 1 (“Blue” Visible, 0.47 µm) and Band 2 (“Red” Visible, 0.64 µm) from the GOES-16 ABI, below, show visible smoke plumes starting around 1940 UTC for the fire near Borger, and closer to 2000 UTC for the fire southeast of Borger. The plumes appear in both visible bands at approximately the same time, although they are more distinct in the blue band because of the enhanced scattering in the atmosphere at that wavelength.

A qualitative method of identifying fires is the Fire RGB that combines the shortwave IR (3.9 µm, the red component of the RGB) with the 2.2 µm (Green) and 1.6 µm (Blue) reflectance channels. As fires become progressively hotter, they emit more and more radiation at shorter wavelengths that can be detected by the ABI on GOES-16, and this alters the color of the RGB over the fire. The Fire RGB animation is shown below. When the 3.9 µm imagery is missing from AWIPS (2005 UTC, 2007-2011 UTC, 2015 UTC because the pixels are hot enough that quality control flags are activated, so the data are not shown), the red pixels in the Fire RGB turn green because no Red component is present (Click here to see the Fire RGB and Shortwave IR animated 2004-2016 UTC).

There are Baseline products that allow a quantitative estimate of fire properties. The animation below shows the Mesoscale Domain Band 7 Shortwave Infrared (3.9 µm) imagery zoomed in over the Texas Panhandle, at 1-minute time-steps; superimposed on the imagery are the GOES-16 Fire Detection Fire Temperature pixels. Fire Products at present are not produced over Mesoscale Domains, so CONUS-scale Fire Products (produced every 5 minutes) are shown instead. The Fire Temperature product in this case has a signal before an obvious signal is present in the 3.9 µm signal — although that could be a function of the 3.9 µm enhancement used here.

An observant reader will notice that the pixels in the GOES-16 Fire Product do not align with the GOES-16 3.9 µm pixels. This is because of the double remapping in the GOES-16 ABI Bands that occurs at NESDIS before data are sent to AWIPS. The Baseline product is not doubly remapped at NESDIS. (This double remapping is being removed from the processing stream shortly).

This animation (from Pete Wolf, SOO in Jacksonville FL), shows a fast-moving fire in the Fire RGB a bit later.  The animation is from the CIRA Slider, similar to this link that shows an animation from 2045 UTC on 23 March to 0045 on 24 March.

 

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