Super Typhoon Goni in the West Pacific Ocean

October 30th, 2020 |

JMA Himawari-8

JMA Himawari-8 “Red” Visible (0.64 µm) images [click to play animation | MP4]

2.5-minute rapid scan JMA Himawari-8 “Red” Visible (0.64 µm) images (above) showed Category 5 Super Typhoon Goni in the West Pacific Ocean on 30 October 2020. The images revealed a very small “pinhole eye”, surface mesovortices within the eye and a trochoidal motion — all characteristics of a tropical cyclone at/near its peak intensity (Goni had a satellite-derived estimate of 160 knots at 00 UTC). The trochoidal “wobble” was more evident in a faster animation.

The corresponding Infrared (10.4 µm) images (below) revealed cloud-top infrared brightness temperatures that were frequently in the -80 to -85ºC range (shades of violet).

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

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

Longwave Infrared (11.2 µm) images with contours of 00 UTC deep-layer wind shear from the CIMSS Tropical Cyclones site (above) indicated Goni was in an environment of very low shear at that time.

Himawari-8 Longwave Infrared (11.2 µm) images, with contours of 0i0 UTC deep-layer wind shear [click to enlarge]

Himawari-8 Longwave Infrared (11.2 µm) images, with contours of 00 UTC deep-layer wind shear [click to enlarge]

===== 31 October Update =====

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

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

Super Typhoon Goni maintained Category 5 intensity for over 24 hours, and actually intensified to 170 knots (JTWC advisory | ADT | SATCON) at 18 UTC on 31 October, just prior to making landfall along Catanduanes Island in the Philippines around 2050 UTC (a closer view of landfall using RealEarth is available here). At 170 knots, Goni became one of the most intense landfalling tropical cyclones on record.

Note the rapid deterioration of the eye upon landfall — this was likely due to a combination of interaction with the terrain of the island, and increasing deep-layer wind shear (below). As it was approaching the Philippines, Goni had been moving over very warm water characterized by high values of Sea Surface Temperature and Ocean Heat Content.

Himawari-8 Water Vapor images, with contours of deep-layer wind shear [click to enlarge]

Himawari-8 Water Vapor images, with contours of deep-layer wind shear [click to enlarge]

A DMSP-16 SSMIS Microwave (85 GHz) image at 2032 UTC is shown below.

DMSP-16 SSMIS Microwave image at 2032 UTC [click to enlarge]

DMSP-16 SSMIS Microwave (85 GHz) image at 2032 UTC [click to enlarge]

 A NOAA-20 VIIRS Infrared Window (11.45 µm) image (below) showed Goni just after 16 UTC.

NOAA-20 VIIRS Infrared Window (11.45 ) image [click to enlarge]

NOAA-20 VIIRS Infrared Window (11.45 µm) image [click to enlarge]

Tropical Storm Epsilon in the Atlantic

October 19th, 2020 |

GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed Tropical Depression 27 as further intensified to become Tropical Storm Epsilon at 15 UTC on 19 October 2020. While the low-level circulation (LLC) generally remained exposed during that time, deep convection was increasing around the LLC (including a small convective burst near the storm center forming around 1630 UTC).

GOES-16 Visible image with plots of available NUCAPS profiles [click to enlarge]

GOES-16 Visible image with plots of available NUCAPS profiles [click to enlarge]

A GOES-16 Visible image with plots of available NOAA-20 NUCAPS profiles (above) showed one valid infrared (CrIS) + microwave (ATMS) sounding (green dot) just southeast of the center of Epsilon at 1640 UTC — that sounding profile (below) revealed a moist (PW = 1.95″) and unstable (MU CAPE = 1066 J/kg, and LI = -3) atmosphere just after the time of development of the convective burst near Epsilon’s center.

NUCAPS profile just southeast of the center of Tropical Storm Epsilon [click to enlarge]

NUCAPS profile just southeast of the center of Tropical Storm Epsilon [click to enlarge]

GOES-16 Visible images with overlays of deep-layer wind shear and GLM Flashes from the CIMSS Tropical Cyclones site (below) indicated that Epsilon was in an environment of moderate shear, with limited lighting activity near the storm center.

GOES-16 “Red” Visible (0.64 µm) images, with overlays of deep-layer wind shear and GLM Flashes [click to enlarge]

GOES-16 “Red” Visible (0.64 µm) images, with overlays of deep-layer wind shear and GLM Flashes [click to enlarge]

A toggle between the MIMIC Total Precipitable Water and Saharan Air Layer products (below) showed that Epsilon was embedded within a pocket of abundant moisture, with dry air situated to the north and northwest.

MIMIC Total Precipitable Water and Saharan Air Layer product [click to enlarge]

MIMIC Total Precipitable Water and Saharan Air Layer product [click to enlarge]

Tropical Storm Epsilon was located over water having Sea Surface Temperature values around 28ºC and a modest Ocean Heat Content (below).

Sea Surface Temperature and Ocean Heat Content [click to enlarge]

Sea Surface Temperature and Ocean Heat Content [click to enlarge]



Hurricane Delta in the Gulf of Mexico

October 8th, 2020 |

GOES-16 “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) and “Red” Visible (0.64 µm) images [click to play animation | MP4]

GOES-16 “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) and “Red” Visible (0.64 µm) images [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Clean” Infrared Window (10.35 µm) images — with and without an overlay of GLM Flash Extent Density — and “Red” Visible (0.64 µm) images (above) showed showed Hurricane Delta as it intensified from a Category 2 to a Category 3 storm over the Gulf of Mexico during the daytime hours on 08 October 2020. Cloud-top infrared brightness temperatures of -90ºC and colder  (yellow pixels embedded within the darker shades of purple) were occasionally seen within the eyewall region of Delta, along with intermittent bursts of lightning activity.

A toggle between Suomi NPP VIIRS Infrared Window (11.45 µm) and Visible (0.64 µm) images of Hurricane Delta shortly before it intensified to a Category 3 storm are shown below; the coldest cloud-top infrared brightness temperature at that time was -93.0ºC.

Suomi NPP VIIRS Infrared Window (11.45 µm) and Visible (0.64 µm) images [click to enlarge]

Suomi NPP VIIRS Infrared Window (11.45 µm) and Visible (0.64 µm) images [click to enlarge]

In a time-matched comparison of Infrared images from Suomi NPP and GOES-16 (below), the coldest cloud-top infrared brightness temperature sensed by GOES-16 was 5.6ºC warmer (-87.4ºC); note the small northwestward parallax displacement that is inherent with GOES-16 imagery over the Gulf of Mexico. The same color enhancement is applied to both images.

Infrared images from Suomi NPP and GOES-16 [click to enlarge]

Infrared images from Suomi NPP (11.45 µm) and GOES-16 (10.35 µm) [click to enlarge]

===== 09 October Update =====

Suomi NPP VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images [click to enlarge]

Suomi NPP VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images [click to enlarge]

In a toggle between Suomi NPP VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images at 0734 UTC or 2:34 am CDT on 09 October (above), the coldest cloud-top infrared brightness temperature was -93.8ºC (just northwest of the storm center).

1-minute GOES-16 Infrared and Visible images (below) showed Category 2 Hurricane Delta making landfall in southwestern Louisiana at 2300 UTC, producing wind gusts as high as 100 mph at Texas Point, Texas.

GOES-16 “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) and “Red” Visible (0.64 µm) images [click to play animation | MP4]

GOES-16 “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) and “Red” Visible (0.64 µm) images [click to play animation | MP4]

The MIMIC Total Precipitable Water product (below) indicated that Hurricane Delta was transporting a large amount of moisture northward across the Gulf of Mexico — rainfall totals included 15.64 inches at Evangeline Gardner, Louisiana.

MIMIC Total Precipitable Water product [click to enlarge]

MIMIC Total Precipitable Water product [click to enlarge]

The MIMIC-TC product (below) showed the deterioration of the eye and eyewall structure as Delta approached the Gulf Coast.

MIMIC-TC product

MIMIC-TC product [click to enlarge]

===== 10 October Update =====

Suomi NPP VIIRS True Color RGB images from 04 and 10 October [click to enlarge]

Suomi NPP VIIRS True Color RGB images from 04 October and 10 October [click to enlarge]

A before (04 October) / after (10 October) comparison of Suomi NPP VIIRS True Color RGB images from the VIIRS Today site (above) revealed a marked increase of turbidity within the more shallow shelf waters of Texas and Louisiana, due to extensive mixing from the wind field associated with Delta. A comparison of VIIRS False Color images from those 2 days (below) highlighted inland areas with significant flooding that resulted from heavy rainfall and/or storm surge (darker shades of blue).

Suomi NPP VIIRS False Color RGB images from 04 October and 10 October [click to enlarge]

Suomi NPP VIIRS False Color RGB images from 04 October and 10 October [click to enlarge]

A GOES-16 River Flood Detection product viewed using RealEarth (below) helped to quantify the severity of flooding resulting from the landfall of Delta.

GOES-16 River Flood product [click to enlarge]

GOES-16 River Flood Detection product valid at 1900 UTC on 10 October [click to enlarge]

Hurricane Teddy and wildfire smoke

September 22nd, 2020 |

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

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

GOES-16 (GOES-East) True Color Red-Green-Blue (RGB) images created using Geo2Grid (above) revealed that the large circulation of Hurricane Teddy (downgraded from a Category 2 to a Category 1 storm at 18 UTC) was drawing hazy filaments of smoke — likely originating from wildfires in the western US — southward from eastern Canada and New England, carrying it across the far western Atlantic Ocean on 22 September 2020. Also of interest (early in the animation) were the narrow fingers of river valley fog across parts of New York, Pennsylvania, Maryland, West Virginia and Virginia.

Although the size of Teddy’s cloud shield was still fairly large, a DMSP-17 SSMIS Microwave (85 GHz) image at 2217 UTC from the CIMSS Tropical Cyclones site (below) showed that no organized core of deep convection remained as the storm began to move across colder waters (Sea Surface Temperature | Ocean Heat Content) and encounter a more hostile environment of increasing deep-layer wind shear.

DMSP-17 SSMIS Microwave (85 GHz) image at 2217 UTC [click to enlarge]

DMSP-17 SSMIS Microwave (85 GHz) image at 2217 UTC [click to enlarge]

GOES-16 CIMSS Natural Color RGB images, with and without an overlay of Aerosol Optical Depth [click to play animation | MP4]

GOES-16 CIMSS Natural Color RGB images, with and without an overlay of Aerosol Optical Depth [click to play animation | MP4]

A larger-scale view of GOES-16 CIMSS Natural Color RGB images — with and without an overlay of Aerosol Optical Depth (above) showed that an elongated plume of smoke stretched westward from New York and Pennsylvania to parts of Wisconsin, Illinois and Iowa. Upward-looking lidar data from the University of Wisconsin – Madison (below) depicted a thick layer of smoke between altitudes of 2-6 km.

Plots of lidar backscatter and depolarization from 12 UTC o n 22 September to 00 UTC on 23 September [click to enlarge]

Plots of lidar backscatter (top) and depolarization (bottom) from 12 UTC on 22 September to 00 UTC on 23 September [click to enlarge]