GOES-17 (GOES-West) True Color Red-Green-Blue (RGB) images (above) showed dense smoke — from Australian bushfires — over the South Pacific Ocean east of New Zealand on 02 January 2020. The imagery was created using Geo2Grid.

Some of this smoke had become entrained into the circulation of an anomalously-deep low pressure system (below).

 

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JMA Himawari-8 Shortwave Infrared (3.9 µm) and Longwave Infrared Window (10.4 µm) images (above) showed a large bushfire (dark black to red pixels in the 3.9 µm imagery) in far southeastern Victoria, Australia — which quickly burned its way to the coast and produced 3 distinct pulses of pyrocumulonimbus (pyroCb) clouds on 29 December 2019. To be classified as a pyroCb, the deep convective cloud must be generated by a large/hot fire (in this case, the Cann River fire complex), and eventually exhibit cloud-top 10.4 µm infrared brightness temperatures of -40ºC and colder (assuring the heterogeneous nucleation of all supercooled water droplets to ice crystals).

The coldest cloud-top 10.4 µm infrared brightness temperature was -62.6ºC (darker green pixels) at 1650 UTC. According to rawinsonde data from Melbourne (below), this corresponded to an altitude near 13 km.

The long/narrow thermal anomaly of the hot bushfire — which burned southwestward all the way to the coast — was outlined in dark black pixels on VIIRS Infrared Window (11.45 µm) images from NOAA-20 and Suomi NPP, as viewed using RealEarth (below).

===== 30 December Update =====

A Himawari-8 Target Sector was positioned over southeastern Australia beginning at 2312 UTC on 29 December, providing images at 2.5-minute intervals — a comparison of Shortwave Infrared and Longwave Infrared Window imagery (above) revealed the formation of several additional pyroCb clouds as southeastern Victoria bushfires continued to grow in number and size. During the daytime, pyroCb cloud tops will appear warmer (darker gray) than those of conventional thunderstorms in the 3.9 µm imagery, due to enhanced reflection of solar radiation off the smaller ice crystals found in the pyroCb anvil. Development of the multiple deep convective pyroCb clouds on this day may have been aided by forcing for ascent provided by an approaching cold front and mid-tropospheric trough, along with favorable upper-tropospheric jet streak dynamics.

The coldest Himawari-8 cloud-top 10.4 µm brightness temperature on 30 December was -73.15ºC at 13:24:41 UTC (violet pixel near the coast); this was 5ºC colder than the coldest temperature of -68.1ºC  — at an altitude of 15 km — on 12 UTC rawinsonde data from Melbourne (below). During the 12-hour period between the 2 soundings, the coded tropopause ascended from a height of 13.1 km (-63.7ºC) at 00 UTC to 14.2 km (-67.5ºC) at 12 UTC.

In a toggle between VIIRS Infrared Window (11.45 µm) images from NOAA-20 and Suomi NPP is shown (below), a large pyroCb cloud was seen moving eastward away from the bushfires.

===== 31 December Update =====

Suomi NPP VIIRS Day/Night Band, Shortwave Infrared, Near-Infrared & Active Fire Product images (above) showed nighttime signatures of the widespread bushfires across Victoria and New South Wales at 1455 UTC on 31 December (or 1:55 am local time on 01 January). In the town of Mallacoota, about 4000 people were forced to evacuate their homes and take shelter along the coast (media report). The surface air temperature at Mallacoota Airport briefly increased to 49ºC (120ºF) at 8:00 am local time as the fires approached (below).

Plot shows temperature recorded at #Mallacoota Airport earlier this morning. https://t.co/Qc5Nzwhqr4 Stay up to date @CFA_Updates @vicemergency pic.twitter.com/1eOKky0oAd

— Bureau of Meteorology, Victoria (@BOM_Vic) December 30, 2019

A sequence of daily Aqua MODIS True Color RGB images with an overlay of VIIRS Fire Radiative Power showed the fires and smoke during the 29-31 December period (below).

A multi-day Himawari-8 GeoColor animation covering the period 28 December – 01 January is available here.

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Full Disk JMA Himawari-8 True Color Red-Green-Blue (RGB) images (above) showed the shadow of an annular solar eclipse as it moved from west to east across the Indian Ocean, Indonesia and West Pacific Ocean on 26 December 2019.

A closer view using images centered over Indonesia is shown below. The small eye of Category 1 Typhoon Phanfone could be seen in the northern portion of the satellite scene. Bright areas of sun glint (south of the eclipse shadow) highlighted regions having light winds — and therefore a relatively flat water surface which behaved like a mirror to reflect a larger amount of sunlight back toward the satellite.

The solar eclipse shadow was also seen on Visible (0.73 µm) images from the CMA FY-2G satellite (below), which is positioned father west over the Equator at 105ºE longitude.

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A sequence of GOES-17 (GOES-West) Low-level (7.3 µm), Mid-level (6.9 µm), Upper-level (6.2 µm) Water Vapor and “Clean” Infrared Window (10.35 µm) images (above) showed a long-lived orographic banner cloud that formed in Southern California and extended about 200 miles to the northeast across southern Nevada on 22 December 2019. The banner cloud was formed by anomalously-strong southwesterly winds (925 hPa | 250 hPa) interacting with the high terrain of Southern California’s Transverse Ranges. At the surface, wind gusts as high as 86 mph were observed.

Within the banner cloud, the coldest GOES-17 Infrared brightness temperatures were in the -60 to -65ºC range — according to rawinsonde data from Vandenberg, California (below), those temperatures corresponded to altitudes in the 12-15 km range.

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