GOES-15 (GOES-West) Visible (0.63 µm) images (above) showed a small, short-lived black cloud that formed south/southwest of Vernal (station identifier KVEL) in northeastern Utah on 06 January 2017. This feature was the result of a fire at an oil well site (media report | well location) that apparently started around 11:30 am local time (1830 UTC); the black cloud from the burning oil tanks — which was first apparent on the 1930 UTC visible image — stood out well against the snow-covered ground. The initial northwestward transport of the smoke plume was consistent with lower-tropospheric winds in Grand Junction, Colorado rawinsonde data at 07 January/00 UTC, which showed southeasterly winds as high as 784 hPa (2185 meters or 7169 feet above ground level). The sounding profile also showed that this height was the top of a well-defined temperature inversion, which acted as a cap to prevent the smoke from reaching higher altitudes (photo).

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.

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Turbulence over the Pacific Ocean affected at least one flight on Tuesday 27 December 2016 near 24º N, 162º E, as indicated by a pilot report issued at 1745 UTC:

PGUA UUA /OV 24N 162E/TM 1745/FL340/TP B777/TB MOD-SEV/RM ZOA

In the animation above of the three Himawari-8 Water Vapor bands (sensing radiation emitted at 6.2 µm, 6.9 µm and 7.3 µm), a characteristic banded gravity wave structure is evident which is associated with the pilot report of moderate to severe turbulence (Note: the ABI instrument on the GOES-R series of satellites will feature these same 3 upper level, mid-level and lower level water vapor bands). In contrast to a turbulence event earlier this month, documented here on this blog, the wave features responsible for this turbulence were more distinct in 8-bit McIDAS-X imagery, and were also apparent in all three water vapor bands.

The Himawari-8 satellite data were used in the subsequent issuance of a SIGMET (Significant Meteorological Information) advisory:

WSPA06 PHFO 271824
SIGPAS

KZAK SIGMET SIERRA 1 VALID 271825/272225 PHFO-
OAKLAND OCEANIC FIR MOD OCNL SEV TURB FCST BTN FL280 AND FL360.
WI N2640 E16810 – N2120 E16810 – N2120 E16240 – N2640 E16250
– N2640 E16810. MOV E 25KT. BASED ON ACFT AND SAT.

The full 11-bit McIDAS-V imagery from the 6.2 µm Water Vapor band on Himawari-8, below, shows multiple ephemeral signatures of potential turbulence. In contrast to the event on 14 December, the gravity waves in this event perturbed clouds enough that they were also apparent in the Infrared Window band, as shown in this toggle between the 10.4 µm and 6.2 µm images. Himawari-8 Infrared Window brightness temperatures exhibited by the gravity wave were in the -30º to -40ºC range at 1740 UTC, which roughly corresponded to altitudes of 30,000-34,000 feet according to data from the 12 UTC rawinsonde report from Minamitorishima RJAM (IR image | text) located about 890 km or 550 miles to the west of the wave feature. Additional Himawari-8 Water Vapor images created using AWIPS II are here for the 6.2 µm imagery (from 1720-1740 UTC); this is a toggle between 6.2 µm and 7.3 µm imagery at 1720 UTC.

The superior spatial resolution of Himawari-8 (2-km at the sub-satellite point) was vital in detecting the gravity wave features causing the turbulence. Water Vapor imagery from COMS-1, with a nominal resolution of 4 km, does not show the features associated with the turbulence report.

Similarly, HimawariCast data that is broadcast at reduced resolution was insufficient to monitor this event. See the toggle below from 1740 UTC.

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A mid-latitude cyclone intensified as it moved northeastward across Nebraska, the eastern Dakotas and northern Minnesota (3-hourly surface analyses) during 25 December – 26 December 2016. GOES-13 (GOES-East) Water Vapor (6.5 µm) images (above) showed distinct banding within the warm conveyor belt, a well-defined dry slot, and a large comma head that formed from the cold conveyor belt. The storm produced blizzard conditions across much of the Northern Plains and Upper Midwest, with heavy snowfall (as much as 22.0 inches in western North Dakota), freezing rain (ice accretion as thick as 0.5 inch in Minnesota and North Dakota) , sleet (up to 2.0 inches deep in Minnesota) and heavy rainfall; in Kansas there were also a few tornadoes (SPC storm reports).

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.

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Rapid-scan (2.5-minute interval) 2-km resolution Himawari-8 Infrared Window (11.45 µm) images (above; also available as a 173 Mbyte animated GIF) showed Category 4 Super Typhoon Nock-Ten making landfall in the Philippines on 25 December 2016. Nock-Ten became the strongest typhoon on record (SATCON | ADT | source) in the Philippines so late in the year:

Supertyphoon #Nockten is the strongest typhoon on record (since 1945) to make landfall in the #Philippines this late in the calendar year. pic.twitter.com/jUzIUOg8hk

— Philip Klotzbach (@philklotzbach) December 25, 2016

A 375-meter resolution Suomi NPP VIIRS Infrared Window (11.45 µm) image at 1724 UTC on 24 December (below; courtesy of William Straka, SSEC) was acquired just before the beginning of the Himawari-8 animations above; note the presence of cloud-top gravity waves propagating southeastward away from the eye of Nock-Ten, in addition to prominent larger-scale transverse banding farther out within the eastern semicircle of the storm.

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