Coronal holes typically result in high-speed solar wind streaming outward, and in this case, directly towards Earth. This scenario sometimes prompts NOAA Space Weather to issue a Geomagnetic Storm Watch, but almost always results in vibrant Aurora Borealis activity when the solar wind reaches Earth. This was the case in the early hours on the 14^th of December, revealed by the VIIRS Day Night Band sensor flying on NOAA’s polar-orbiting satellites. 

The following 3 images were acquired by the NOAA-21 satellite:

These 3 images were acquired by the NOAA-20 satellite:

Three images were also acquired by the Suomi-NPP satellite:

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Target Sector (2.5-minute interval) JMA Himawari-9 AHI Red Visible (0.64 µm) and Clean Infrared Window (10.4 µm) images (above) showed the brief development of a ragged eye with Cyclone Jasper as the storm approached the coast of Far North Queensland, Australia — prior to it making landfall north of Cairns around 1200 UTC on 13 December 2023.

In Synthetic Aperture Radar (SAR) wind speed images from RCM-3 at 1956 UTC on 12 December and 0854 UTC on 13 December (source), a swath of higher speeds (having maxima of 65.78 knots and 49.62 knots, respectively) was seen within the southern semicircle of the eyewall (below).

A GCOM-W1 AMSR2 Microwave (85 GHz) image at 1554 UTC on 13 December (below) also displayed higher reflectivity within the southern eyewall, moving inland near and just north of Cairn surface observation site.

Himawari-9 Infrared Window (11.2 µm) images from the CIMSS Tropical Cyclones site (below) showed that Jasper was moving through an environment of low deep-layer wind shear — which, in addition to its motion across modestly-warm water (SST | OHC) favored some intensification. In fact, Jasper did intensify to 60 knots at 0600 UTC on 13 December (SATCON), about 6 hours prior to landfall,

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National Weather Service Pago Pago Facebook posts on 11 December describe an atmosphere primed for heavy rain and lightning, the latter Facebook also shown below. Band 13 animation, above, shows persistent deep convection over the Samoan Islands. The convection develops and drifts southward.

MIMIC Total Precipitable Water over the south Pacific shows moist air over Samoa being drawn poleward in an atmospheric river. (Cyclone Jasper (see this also) along the northeast coast of Australia is also apparent).

ASCAT Scatterometry data from Metop-B, below (source), shows strong surface convergence over the Samoan Islands.

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Lightning events on 12 December are shown below from this link. In this case, GOES-18 Flash Extent Density field are overlain on GeoColor imagery. Abundant lightning is occurring north and south of the Samoan Islands. An Airmass RGB animation from the same website (here), shows the persistent southward motion of moist tropical air over the Samoan Islands.

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Overlapping 1-minute Mesoscale Domain Sectors from GOES-16 (GOES-East) provided imagery at 30-second intervals during an outbreak of severe thunderstorms (SPC Storm Reports) across parts of the Mid-South and Deep South on 09 December 2023. “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (above) included time-matched plots of SPC Storm Reports for a  thunderstorm that produced a EF3-rated tornado which was responsible for 3 deaths and 62 injuries in the Clarksville, Tennessee (KCKV) area. The coldest cloud-top 10.3 µm infrared  brightness temperatures were in the -60 to -65ºC range (darker red enhancement).

1-minute GOES-16 Visible and Infrared images with/without an overlay of GLM Flash Extent Density (below) showed pulses of cold overshooting tops (brighter white infrared pixels) and brief lightning jumps associated with the Clarksville supercell thunderstorm as it moved across Montgomery County in Tennessee into Todd County in Kentucky.

30-second GOES-16 Infrared images (below) showed a later thunderstorm that produced a EF2-rated tornado which was responsible for an additional 3 fatalities in Madison, Tennessee (just north of Nashville KBNA).

1-minute GOES-16 Infrared images with/without an overlay of GLM Flash Extent Density (below) showed lightning activity associated with the thunderstorm that produced the Madison tornado (in Davidson County) — as with the Clarksville storm, pulses of cold overshooting tops and brief lightning jumps were observed as the tornadic thunderstorm progressed across the area.

Cursor sampling of 2-km resolution GOES-16 10.3 µm brightness temperature along with the operational Cloud Top Temperature and CLAVR-x Cloud Top Height derived products for the Clarksville TN tornadic thunderstorm and the Madison TN tornadic thunderstorm (below) indicated that Cloud Top Temperatures were in the -65 to -66°C range, with Cloud Top Heights in the 43000-45000 ft range (the CLAVR-x Cloud Top Height product was shown here, since its 2-km resolution was superior to the legacy 10-km resolution Cloud Top Height product currently available in AWIPS).

Those GOES-16 Cloud Top Temperature and Cloud Top Height values were a bit colder/higher than the Most Unstable air parcel Maximum Parcel Level (MU MPL) calculated using rawinsonde data from Nashville, Tennessee rawinsonde data at 1200 UTC on 09 December, shown below (source). Unfortunately, a 0000 UTC / 10 December Nashville rawinsonde report was not available.

A larger-scale view of 30-second GOES-16 Infrared imagery is shown below, spanning the ~13-hour period from 1900 UTC on 09 December to 0752 UTC on 10 December — which depicted more of the nighttime SPC Storm Reports across parts of northern Mississippi, Alabama and Georgia.

Many of these severe thunderstorms were developing within a corridor of moisture and instability ahead of an advancing cold front, as seen in 5-minute GOES-16 Visible images combined with Total Precipitable Water and Lifted Index / CAPE Derived Stability Indices in cloud-free skies (below).

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