A long-track tornado moved through Nashville (north Nashville to Lockeland Springs then towards Lebanon) early in the morning on 3 March 2020. (ProbSevere for this event is also discussed in this blog post; A GLM View of the storm is here) The Band13 mp4 animation, above (Click here for an animated gif), from 0313 through 0722 UTC shows the long-lived storm forming over western Tennessee and rolling eastward into Nashville after midnight. As the storm approached Nashville, the storm top frequently showed isolated cold pixels (yellow in the enhancement) that are testament to the strong convection, and an above-anvil cirrus plume (AACP) might be there too. All of these structures are consistent with a tornadic storm. The 00 UTC Nashville Sounding shows a favorable environment as well.

1-minute GOES-16 Infrared images with plots of time-matched SPC Storm reports is shown below, covering the period 0300-0802 UTC. The color enhancement applied to those images is slightly different — and the pulsing overshooting tops are easier to see as highlighted with darker shades of orange.

Shortly after the tornado passed through Nashville, NOAA-20 overflew Tennessee. The toggle below shows the GOES-16 ABI Band 13 (10.3 µm) infrared imagery, the NUCAPS Sounding Location, and the computed Total Totals Index from the NUCAPS thermodynamic information. Values exceeding 50 are south and west of the thunderstorm complex. NUCAPS soundings are showing a thermodynamically unstable environment.

The high-resolution VIIRS instruments on NOAA-20 gives a high-resolution view of the storm, as shown below.  The figure includes the 11.45 µm VIIRS I05 infrared imagery (from Real Earth) and also shows a 5-minute GLM Group Density accumulation with a profound maximum (values exceeding 250!) over Lebanon TN.  The morning NOAA-20 orbit on 3 March was to the east of Tennessee (source), so a parallax shift between the GLM data from GOES-16 and the VIIRS I05 data will occur.

A zoomed-out toggle between VIIRS I05 and the Day Night Band (below, courtesy William Straka, CIMSS), (Click here to view the I05 with a different enhancement) shows the storm to the east of Nashville.  The quarter New Moon (that was below the horizon) offered no clear view of the cloud tops, but lightning illumination is apparent.

This long storm in a favorable environment was captured well by the NOAA/CIMSS ProbSevere product.  The animation below tracks the storm across much of northwest and north-central Tennessee.  Time-series plots of the radar object (#181389) associated with the Nashville tornado are here:  ProbTor (including components), ProbSevere (including components), and ProbSevere, ProbHail and ProbTor values.  The cyclic nature of the storm is apparent.  ProbSevere/ProbTor/ProbHail values were very high when the Nashville tornado was on the ground (around 0640 UTC).

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A project spearheaded by Bill Smith Sr and Qi Zhang at Hampton University (they are also affiliated with CIMSS) takes Polar Hyperspectral (PHS) data and blends it with GOES-16 ABI data.  Those fields that exploit the high spectral resolution from sounders in polar orbit (such as IASI or CrIS) and the high spatial and temporal resolution from GOES are then input into numerical models.  Output is here.  The better representation of moisture fields in these fields can help a model better define where strong convection will or will not occur.  The animation below shows initial fields of the Significant Tornado Parameter from 0300 – 0800 UTC on 3 March 2020. Compare the animation to initial fields of STP in a model that does not include the assimilated hyperspectral data here.

What did the forecast for 0600 UTC look like from this model that includes polar hyperspectral data?  That is shown below, with a series of model runs.  There is run-to-run variability, but overall the forecast simulations show a peak in the STP parameter near Nashville. (This PDF compares model runs with and without Polar Hyperspectral Data; adding the satellite data helps the model focus convection where it occurs, mostly because the moisture fields are more accurately defined).

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As scheduled, GOES-15 has sent its last image (More information from NOAA’s Office of Satellite and Product Operations OSPO)  .  The final image sent was a 1552 UTC Southern Hemisphere sector, shown above (courtesy Tim Schmit).   (One of the final Sounder images is here). However, the satellite is not gone for good:  it is scheduled to transmit data again in August of this year, when the GOES-17 Loop Heat Pipe issue again renders GOES-West imagery incomplete during the eastern/central Pacific Ocean Hurricane season.  (This website shows more specifics)

GOES-15 became the operational GOES-West satellite — replacing GOES-11 — back in early December 2011 (Blog Post;  GOES-11 replaced GOES-10 as GOES-West back in 2006 (Blog Post)).  GOES-15 ceased being the operational GOES-West when GOES-17 became operational (February 12, 2017), but GOES-15 has continued to transmit data to supplement imagery lost because of the GOES-17’s Loop Heat Pipe.

Added: The Science Test for GOES-15 is available here.

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EUMETSAT Meteosat-11 Water Vapor (6.25 µm) images (above) showed the large field of strong surface winds associated with Storm Jorge as it approached the British Isles on 29 February – 01 March 2020. Peak wind gusts of 70 knots were recorded in Ireland.

Surface analyses from the Ocean Prediction Center (below) indicated that the Hurricane Force occluded low reached a minimum pressure of 952 hPa at 06 UTC on 29 February.

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GOES-16 (GOES-East) Visible (0.64 µm) images (above) revealed a cloud arc which marked the leading edge of a Tehuano wind event — air behind a cold front plunged southward across the Gulf of Mexico during the previous day, crossed the mountains of Mexico through Chivela Pass (topography) , and emerged over the Pacific Ocean on 27 February 2020. Within the western portion of the gap wind flow, ASCAT winds speeds were as high as 32 knots at 1540 UTC — but closer to the coast the Ocean Prediction Center was initially forecasting an area of Storm Force winds (downgraded to Gale Force winds later in the day).

On a GOES-16 Visible image with plots of available NOAA-20 NUCAPS profiles (below), the location of one profile immediately offshore (Point 1) and another just ahead of the Tehauno cloud arc (Point 2) are highlighted.

A toggle between the NUCAPS profile immediately offshore (Point 1, at 15.39 N latitude 94.55 W longitude) and the profile just ahead of the Tehauno cloud arc (Point 2, at 7.29 N latitude 93.95 W longitude) is show below. Note that Total Precipitable Water values were 1.78 inches ahead of the cloud arc, compared to 1.16 inches immediately off the coast of Mexico where the dry gap winds were entering the Gulf of Tehuantepec.

In a comparison of Visible images from GOES-17 (GOES-West) and GOES-16 (GOES-East), haziness in the Gulf of Tehuantepec (best seen with GOES-16, due to a larger forward scattering angle) highlighted blowing dust that was being carried offshore by the strong gap winds.

GOES-16 True Color Red-Green-Blue (RGB) images created using Geo2Grid (below) provided a clearer view of the blowing dust plumes in the Gulf of Tehuantepec.

VIIRS True Color RGB images from Suomi NPP and NOAA-20 as viewed using RealEarth are shown below.

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