Rapid intensification of Super Typhoon Surigae

April 16th, 2021 |

JMA Himawari-8 Infrared Window (10.4 µm) images [click to play animation]

JMA Himawari-8 Infrared Window (10.4 µm) images [click to play animation]

2.5-minute interval rapid scan JMA Himawari-8 Infrared Window (10.4 µm) images (above) showed Typhoon Surigae undergoing rapid intensification (ADT | SATCON) to become a Category 4 storm as of 18 UTC on 16 April 2021.

A DMSP-16 SSMIS Microwave (85 GHz) image from the CIMSS Tropical Cyclones site (below) displayed a well-defined eye, with distinct spiral bands feeding into the eyewall.

DMSP-16 SSMIS Microwave (85 GHz) image at 1944 UTC [click to enlarge]

DMSP-16 SSMIS Microwave (85 GHz) image at 1944 UTC [click to enlarge]

After sunrise, Himawari-8 “Red” Visible (0.64 µm) images (below) showed the relatively compact eye, with hints of low-level mesovortices within the eye.

JMA Himawari-8 "Red" Visible (0.64 µm) images [click to play animation]

JMA Himawari-8 “Red” Visible (0.64 µm) images [click to play animation]

===== 17 April Update =====

JMA Himawari-8 Infrared Window (10.4 µm) images [click to play animation | MP4]

JMA Himawari-8 Infrared Window (10.4 µm) images [click to play animation | MP4]

Another period of rapid intensification occurred overnight, and as of 12 UTC on 17 April Surigae had become a Category 5 Super Typhoon — 2.5-minute interval rapid scan Himawari-8 Infrared images (above) showed the well-defined eye as the storm tracked northwestward across the Philippine Sea (just east of the Philippines). A faster animation (GIF | MP4) helped to highlight the trochoidal motion (wobble) of the eye — a behavior often seen with intense tropical cyclones. The 21 UTC advisory from JTWC listed sustained winds of 165 knots, and objective intensity estimates from ADT and SATCON were around 170 knots.

An animation of Himawari-8 Infrared images with an overlay of deep-layer wind shear (below) indicated that Surigae was moving through a region of low to moderate wind shear; the storm was moving across very warm water (SST + OHC).

Himawari-8 Infrared images, with contours of deep-layer wind shear at 18 UTC [click to enlarge]

Himawari-8 Infrared images, with contours of deep-layer wind shear at 18 UTC [click to enlarge]

Around the time that Surigae was reaching its peak intensity, a Suomi NPP VIIRS Day/Night Band (0.7 µm) image several hours before sunrise (below) revealed concentric mesospheric airglow waves propagating away from the energetic Category 5 tropical cyclone. There were also some bright pixels indicating lightning activity along the inner edge of the northern eyewall.

Suomi NPP VIIRS Day/Night Band (0.7 µm) image [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) image [click to enlarge]

Prescribed burns across the central US

April 2nd, 2021 |

GOES-16 True Color RGB images [click to play animation | MP4]

GOES-16 True Color RGB images [click to play animation | MP4]

Every Spring season, many states conduct prescribed burns as a part of land management within forests, parks, wetlands etc — and GOES-16 (GOES-East) True Color RGB images created using Geo2Grid (above) showed a large number of smoke plumes associated with prescribed burning across parts of the central US on 02 April 2021.

Of particular interest was a very long smoke plume that was seen streaming northward across southern Lake Michigan — a closer view using GOES-16 True Color RGB images centered over that area (below) indicated that 2 separate plumes merged into one larger/longer smoke plume that continued to drift north-northeastward toward the west coast of Lower Michigan. The source of these smoke plumes was the combination of a small prescribed burn and a larger wildfire within the Indiana Dunes National Park near the coast of Lake Michigan.

GOES-16 True Color RGB images [click to play animation | MP4]

GOES-16 True Color RGB images [click to play animation | MP4]

375-meter resolution Suomi NPP VIIRS True Color RGB and Shortwave Infrared (3.74 µm) images (below) provided a more detailed view of the smoke plume over far southern Lake Michigan, as well as thermal anomalies (clusters of hot pixels) associated with the industrial sites producing the smoke.

Suomi NPP VIIRS True Color RGB and Shortwave Infrared (3.74 µm) images [click to enlarge]

Suomi NPP VIIRS True Color RGB and Shortwave Infrared (3.74 µm) images [click to enlarge]

The pair of 1-minute GOES-16 Mesoscale Domain Sectors was positioned to cover the northern and southern portions of the central US  — and a small overlap of the sectors provided 30-second imagery over the Nebraska/Kansas border area. 30-second GOES-16 Fire Temperature RGB images (below) offered a qualitative view of the locations and relative intensities of a few prescribed burns in the southwestern portion of Nebraska.

GOES-16 Fire Temperature RGB images [click to play animation | MP4]

GOES-16 Fire Temperature RGB images [click to play animation | MP4]

Severe weather across the Deep South and Mid-South

March 25th, 2021 |

GOES-16 “Red” Visible (0.64 µm) images, with time-matched SPC Storm Reports plotted in red [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) images, with time-matched SPC Storm Reports plotted in red [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 “Red” Visible (0.64 µm) images (above) and “Clean” Infrared Window (10.35 µm) images (below) include time-matched plots of SPC Storm Reports that were produced by a number of supercell thunderstorms that developed and moved across the Deep South and Mid-South on 25 March 2021. The highest concentration of tornadoes occurred in Alabama, including one that was responsible for multiple fatalities in Ohatchee around 1842 UTC.

GOES-16 “Clean” Infrared Window (10.35 µm) images, with time-matched SPC Storm Reports plotted in cyan [click to play animation | MP4]

GOES-16 “Clean” Infrared Window (10.35 µm) images, with time-matched SPC Storm Reports plotted in cyan [click to play animation | MP4]

In a time-matched comparison of Infrared images from Suomi NPP (overpass times) and GOES-16 at 1831 UTC (below)the coldest overshooting top infrared brightness temperature sensed by the VIIRS instrument on Suomi NPP was -78ºC, compared to -72ºC by the ABI  instrument on GOES-16. Note the small northward parallax displacement that is inherent with GOES-16 imagery over that region. The same color enhancement is applied to both images.

GOES-16 “Clean” Infrared Window (10.35 µm) and Suomi NPP VIIRS Infrared Window (11.45 µm) images at 1921 UTC [click to enlarge]

GOES-16 “Clean” Infrared Window (10.35 µm) and Suomi NPP VIIRS Infrared Window (11.45 µm) images at 1831 UTC [click to enlarge]

Eruption of Mount Etna

March 24th, 2021 |

Meteosat-11 Ash Height images [click to play animation | MP4]

Meteosat-11 Ash Height images [click to play animation | MP4]

EUMETSAT Meteosat-11 Ash Height retrievals from the NOAA/CIMSS Volcanic Cloud Monitoring site (above) showed that an eruption of Mount Etna in Sicily, Italy on 24 March 2021 produced an ash cloud which rose to heights of 7-8 km (darker shade of green).

The corresponding Meteosat-11 Ash Loading images are shown below — ash loading appeared to be light to moderate within much of the volcanic cloud.

Meteosat-11 Ash Loading images [click to play animation | MP4]

Meteosat-11 Ash Loading images [click to play animation | MP4]

Ash Loading values retrieved using Suomi NPP VIIRS data at at 1200 UTC (below) were notably higher than those from Meteosat-11, given the higher spatial resolution and additional spectral band data available from the VIIRS instrument.

Suomi NPP VIIRS Ash Loading at 1200 UTC [click to enlarge]

Suomi NPP VIIRS Ash Loading at 1200 UTC [click to enlarge]

A toggle between VIIRS True Color RGB images from NOAA-20 and Suomi NPP as viewed using RealEarth (below) revealed hues of tan to light brown within the volcanic plume, further supporting the presence of an elevated ash content.

VIIRS True Color RGB images from NOAA-20 and Suomi NPP [click to enlarge]

VIIRS True Color RGB images from NOAA-20 and Suomi NPP [click to enlarge]