GOES-16 (GOES-East) “Clean” Infrared Window (10.35 µm) images (above) showed pockets of cold surface brightness temperatures — darker blue represented the -30 to -35ºC (-22 to -31ºF) range — over parts of North Dakota during the 4 hours leading up to sunrise on 10 December 2019. As of 12 UTC, the coldest locations in the US (including Alaska) were Rugby and Watford City, North Dakota with -22ºF; however, Grand Forks International Airport later dropped to -25ºF at 1245 UTC.

With the cold and dry arctic air mass in place across the Upper Midwest, GOES-16 Low-level (7.3 µm) and Mid-level (6.9 µm) Water Vapor imagery (below) was able to sense the thermal contrast between cold, snow-covered land surfaces and the still-unfrozen reservoirs along the Missouri River in North Dakota and South Dakota.

GOES-16 Water Vapor weighting functions calculated using 12 UTC rawinsonde data from Aberdeen, SD (below) showed the downward shift of the peak pressures for all 3 spectral bands — with some contributions of radiation originating from the surface indicated for both the 7.3 µm and 6.9 µm bands.

According to the climatology of Precipitable Water for Aberdeen SD (below), the 12 UTC value of 0.06 inch tied the record minimum value for that date/time. The 12 UTC sounding at Bismarck ND failed at a pressure level near 400 hPa — but the PW value of 0.05 inch calculated from that data would be slightly less than the record minimum value of 0.06 inch for that date/time.

On a NOAA-20 VIIRS Visible (0.64 µm) image with plots of available NUCAPS sounding locations (below), soundings northeast of Bismarck KBIS and southeast of Aberdeen KABR are denoted by 1 and 2, respectively.

Plots of the NOAA-20 NUCAPS sounding profiles northeast of Bismarck KBIS and southeast of Aberdeen KABR around 19 UTC are shown below. Precipitable Water values calculated for these two soundings remained quite low, at 0.03 inch and 0.04 inch.

Examples of “river effect” cloud plumes — produced by cold air flowing across deep, relatively warm water in some of the Missouri River reservoirs — were evident in GOES-16 “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images over North Dakota (above) and South Dakota (below).

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1-minute Mesoscale Domain Sector GOES-17 (GOES-West) Low-level Water Vapor (7.3 µm), Mid-level Water Vapor (6.9 µm), Upper-level (6.2 µm) Water Vapor and “Red” Visible (0.64 µm) images (above) showed orographic wave clouds and banner clouds associated with strong winds across south-central Alaska on 09 December 2019. These strong winds were associated with flow around a deepening Storm Force low that was moving from the Gulf of Alaska to the Bering Sea (surface analyses). Downsloping (southeasterly) chinook winds (topography) caused the air temperature at Anchorage International Airport (PANC) to rise to 51ºF** at 2200 UTC (11:00 am local time) — which set a new record high for the month of December at that site (** the 5-minute ASOS temperatures are reported in ºC — and rounding errors caused the converted temperature to be listed as 52ºF).

McHugh Creek observing station along the Seward Highway south of Potter Marsh reported a wind gust to 113 mph at 8:50am! The High Wind Warning has been adjusted to account for these higher-than-expected gusts. #AKwx

The warning text can be found here: https://t.co/5Jjc11brlj

— NWS Anchorage (@NWSAnchorage) December 9, 2019

The Storm Force low was also helping to advect an atmospheric river of moisture northward toward south-central Alaska, which was depicted in hourly images of the MIMIC Total Precipitable Water product (below). Heavy rainfall (including 1.30 inch at Homer) resulting from this influx of moisture produced rises in some rivers in the Kenai Peninsula south of Anchorage.

 

Rainfall combined w/ snowmelt over the past 24 hrs has resulted in significant rises in small streams/rivers on the #KenaiPeninsula. #AnchorRiver at is expected to rise into Moderate Flood stage tonight. Hwys in the area will start to experience problems with high water. #AKwx pic.twitter.com/lW8vMtRk0b

— NWS Anchorage (@NWSAnchorage) December 10, 2019

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A brief eruption of the Whakaari volcano on White Island, New Zealand occurred around 0110 UTC on 09 December 2019 — “Red” Visible (0.64 µm) images from JMA Himawari-8 and GOES-17 (GOES-West) showed the small volcanic cloud as it fanned out east of the island (above).

A signature of the volcanic cloud was also seen in VIIRS True Color Red-Green-Blue (RGB) and Infrared Window (11.45 µm) images from NOAA-20 and Suomi NPP, as viewed using RealEarth (below). The cloud exhibited a rather warm infrared brightness temperature, since the Wellington VAAC only estimated the maximum height to be

The volcanic plume contained elevated levels of SO2 which drifted south-southeastward, as seen in a McIDAS-V image of Sentinel-5 TROPOMI Vertical Column SO2 at 0206 UTC (below).

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2.5-minute interval rapid scan JMA Himawari-8 AHI “Clean” Infrared (10.4 µm) images (above) showed Typhoon Kammuri as it made landfall in the Philippines around 1500 UTC on 02 December 2019. Kammuri rapidly intensified from a Category 2 to a Category 4 storm (ADT | SATCON) shortly before landfall — it had been moving over very warm water (Sea Surface Temperature | Ocean Heat Content) in the Philippine Sea.

VIIRS Infrared Window (11.45 µm) from Suomi NPP at 1707 UTC and NOAA-20 at 1757 UTC viewed using RealEarth (below) depicted Kammuri 2-3 hours after landfall.

GCOM-W1 AMSR2 Microwave (85 GHz) imagery at 1725 UTC (below) revealed a large eye and nearly circular eyewall.

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