GOES-13 (GOES-East) Visible (0.63 µm) images (below) also displayed the dark smoke plume. The viewing angles from the 2 satellites were similar (~53 degrees from GOES-15 vs ~57 degrees from GOES-13), but the time sampling was slightly better from GOES-15 (due to the extra “SUB-CONUS” scan images at :11 and :41 minutes nearly every hour). Image frequency will be even better with the GOES-R series of satellites (beginning with GOES-16), with routine scans every 5 minutes; the visible image spatial resolution will also be improved (to 0.5 km, vs 1.0 km with the current GOES).MODIS Visible (0.645 µm), Shortwave Infrared (3.7 µm) and Infrared Window (11.0 µm) images from a 2036 UTC overpass of the Aqua satellite (below) showed the black smoke cloud in the Visible, but there was no evidence of a fire “hot spot” in the Shortwave Infrared (the media report indicated that the fire was extinguished about 2 hours after it started, which would have been around or just before the time of the MODIS images). On the Infrared Window image, the smoke plume actually did exhibit a slightly colder (darker blue color enhancement) signature, which is unusual since conventional fire and wildfire smoke is normally transparent to thermal radiation. A view of the 250-meter resolution Aqua MODIS true-color Red/Green/Blue (RGB) image from the MODIS Today site is shown below.
A noteworthy characteristic of the storm was very strong winds — a closer view of GOES-13 Water Vapor imagery with hourly plots of surface wind gusts (in knots) is shown below.Note the swath of wind gusts in the 50-60 knot range which progressed across central and northeastern Nebraska into northwestern Iowa and finally southwestern Minnesota during the 02 UTC to 12 UTC period on 26 December — this was pointed out in a tweet by Anthony Sagliani as a “sting jet” feature:
Beautiful example of a bent-back occlusion/sting jet tonight in the Northern Plains, complete with a "false" warm sector. pic.twitter.com/36ChcoGFqS
— Anthony Sagliani (@anthonywx) December 26, 2016
As observed in previous sting jet cases (03 Jan 2012 | 28 Oct 2013), the strongest winds occurred near the curved “scorpion tail” signature seen in the water vapor imagery (which marked the leading edge of the cold conveyor belt as it advanced into the rear edge of the dry slot of the cyclone circulation).
A comparison of Aqua MODIS Visible (0.65 µm), Infrared Window (11.0 µm) and Water Vapor (6.7 µm) images at 2001 UTC on 25 December is shown below.A closer view with Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 1952 UTC on 25 December (below) showed a detailed view of the banded cloud structures from Kansas into South Dakota, as well as small overshooting tops associated with thunderstorms in southeastern South Dakota and southwestern Minnesota. This storm produced the first Christmas Day thunderstorms on record in both Sioux Falls and Rapid City, South Dakota; thundersnow was also observed in Bismarck, North Dakota.
A closer view using GOES-13 Water Vapor imagery with overlays of hourly reports of surface winds and wind gusts (below) showed that wind speeds remained strong enough to create travel-restricting blowing snow over eastern North Dakota and western Minnesota even into the early hours of 08 December (due to the continuing strong pressure gradient between the large low in Canada and the arctic high that was moving into Montana and Wyoming.In the wake of the storm on 09 December, a southeastward flow of cold arctic air (with surface air temperatures in the 0 to -15º F range) over the still-unfrozen water of Lake Sakakawea (which exhibited MODIS Sea Surface Temperature values as warm as 37.9º F) caused lake effect cloud bands to form and extend downwind of the lake — these cloud bands were very evident in a comparison of 250-meter resolution Aqua MODIS true-color and false-color Red/Green/Blue (RGB) images from the MODIS Today site (below). In the false-color image, snow/ice appears as shades of cyan, in contrast to supercooled water droplet clouds which appear as shades of white. The 1.6 µm snow/ice band used to create the MODIS false-color image will also be available with the ABI instrument on the GOES-R series (beginning with GOES-16). With a fresh, deep snow cover and cold arctic air in place, strong nocturnal radiational cooling allowed North Dakota to experience its first -30º F low temperatures of the season on the morning of 10 December. Aqua MODIS Land Surface Temperature values at 0939 UTC or 3:39 am local time (below) were as cold as -39º F (darker violet color enhancement) near the sites that reported the -30º F low temperatures.
Even though cloud cover was increasing, a detailed view of the fire hot spot was provided by an AWIPS II image of 375-meter resolution Suomi NPP VIIRS Shortwave Infrared (3.74 µm) data at 1815 UTC on 28 November (below). An AWIPS I version of this image is available here. Due to the cloudiness, no discernible hot spot appeared on the lower-resolution 1815 UTC GOES-13 Shortwave Infrared image.Props to NWS meteorologist Carl Jones for spotting this somewhat unexpected result: the glow of the fire was evident on the following nighttime Suomi NPP VIIRS Day/Night Band (0.7 µm) image, even though there was a thick layer of clouds over the fire itself:
— Carl Jones (@northflwx) November 29, 2016
An AWIPS II image comparison of VIIRS Infrared Window (11.45 µm), Shortwave Infrared (3.74 µm) and Day/Night Band (0.7 µm) data at 0816 UTC on 29 November is shown below. Cloud-top Infrared Window brightness temperatures were in the -40 to -55º C range over the fire region (such air temperatures were foundd within the 9.5-10.5 km altitude range on the Nashville sounding when the cloud band was over central Tennessee at 00 UTC). While no fire hot spot signature was evident on the Shortwave Infrared image (due to masking by the clouds), the very distinct bright glow of the fire (which appeared rather large in size, due to scattering of light by the water and ice particles present in the various cloud layers) was seen on the Day/Night Band image. AWIPS I versions of these images are available here.Additional information is available on the Wildfire Today site (post 1 | post 2 | post 3 | post 4 | post 5).