Hurricane Force low pressure system off the US East Coast

April 1st, 2020 |

GOES-16 “Red” Visible (0.64 µm), Mid-level Water Vapor (6.9 µm) and Air Mass RGB images [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm), Mid-level Water Vapor (6.9 µm) and Air Mass RGB images [click to play animation | MP4]

A sequence of GOES-16 (GOES-East) “Red” Visible (0.64 µm), Mid-level Water Vapor (6.9 µm) and Air Mass Red-Green-Blue (RGB) mages (above) showed an occluding Hurricane Force low pressure system (surface analyses) off the US East Coast on 01 April 2020. In the Air Mass RGB images, darker red areas just south of the storm center indicated the presence of higher amounts of total column ozone, brought about by a lowering tropopause — RAP40 model fields of the PV1.5 pressure (representing the height of the “dynamic tropopause”) suggested that the tropopause had descended below the 500 hPa pressure level later in the day.

The hurricane-force winds at the surface were creating seas as high as 33 feet. The milky/hazy signature of a highly-agitated sea surface + sea spray — immediately south of the convection around the core of the storm — was evident in GOES-16 True Color RGB images, created using Geo2Grid (below).

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

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

GOES-16 Visible images with an overlay of GLM Flash Extent Density (below) revealed that lightning activity gradually decreased within convection surrounding the core of the low during the day.

GOES-16 “Red” Visible (0.64 µm), Mid-level Water Vapor (6.9 µm) and Air Mass RGB images [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) images with an overlay of GLM Flash Extent Density [click to play animation | MP4]

As the storm was becoming organized near the Southeast US coast during the preceding overnight hours, a toggle between Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 0627 UTC (below) showed widespread mesospheric airglow waves in the Day/Night Band — these waves were likely generated by the approach of an upper-tropospheric jet streak.

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

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

Addition information about this event is available on the Satellite Liaison Blog.

What has the Large Iceberg (A68) been up to this year?

March 31st, 2020 |

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

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

A very large iceberg broke off the Larsen-C Ice Shelf on the Antarctic Peninsula in July 2017 (recall this CIMSS Satellite Blog post). While NOAA’s GOES-16 ABI visible sensors may not be ideal, they can monitor the iceberg’s location if the cloud cover is not too thick. The animation above shows the first 31 days of 2020, with just one image per day. More information from the National Ice Center.

H/T to @annamaria_84 for this tweet using Sentinel3 images:

Contrails over Wisconsin, and a mesovortex moving across Indiana

March 31st, 2020 |

GOES-16

GOES-16 “Red” Visible (0.64 µm), Near-Infrared “Cirrus” (1.37 µm), Near-Infrared “Snow/Ice” (1.61 µm), Upper-level Water Vapor (6.2 µm), Mid-level Water Vapor (6.9 µm), Low-level Water Vapor (7.3 µm), “Clean” Infrared Window (10.35 µm) and Day Cloud Phase Distinction RGB images [click to play animation | MP4]

A sequence of GOES-16 (GOES-East) “Red” Visible (0.64 µm), Near-Infrared “Cirrus” (1.37 µm), Near-Infrared “Snow/Ice” (1.61 µm), Upper-level Water Vapor (6.2 µm), Mid-level Water Vapor (6.9 µm), Low-level Water Vapor (7.3 µm), “Clean” Infrared Window (10.35 µm) and Day Cloud Phase Distinction Red-Green-Blue (RGB)  images (above) showed both circular and linear contrails over southern Wisconsin on 31 March 2020. The circular contrail was likely created by military aircraft (Wisconsin Air National Guard) performing training operations.

A toggle between GOES-16 Visible and Cirrus images at 1601 UTC (below) indicated that the darker signature seen in Visible imagery was actually the shadow from the high-altitude contrails being cast upon the top of the low-level stratus clouds.

GOES-16 "Red" Visible (0.64 µm), and Near-Infrared "Cirrus" (1.37 µm) images [click to enlarge]

GOES-16 “Red” Visible (0.64 µm), and Near-Infrared “Cirrus” (1.37 µm) images [click to enlarge]

Another feature of interest was revealed by 1-minute Mesoscale Domain Sector GOES-16 Visible images — a mesovortex that was moving southwestward from southwest Michigan across northwestern Indiana (below). However, the small-scale circulation of the vortex was not captured by 1-minute GOES-16 Derived Motion Winds.

GOES-16 "Red" Visible (0.64 µm) images with plots of Derived Motion Winds (yellow) [click to enlarge]

GOES-16 “Red” Visible (0.64 µm) images, with Derived Motion Winds plotted in yellow [click to play animation | MP4]

Year-long Animations of Visible and Infrared Images

March 26th, 2020 |

True-color visible imagery global montage from 6 March 2019 – 5 March 2020 (Click to launch containerized YouTube Vide)

A previous blog post (here) has shown 1-month animations of true-color visible imagery from geostationary satellites (GOES-16, GOES-17, Himawari-8, Meteosat-11 and others) wherein local noon longitudinal strips are blended together to create a global view. (Imagery courtesy Rick Kohrs, SSEC) (See also this blog post for an explanation). The animation above (Click it to view a YouTube animation within a container) shows visible true-color imagery for each day from 6 March 2019 through 5 March 2020.

The infrared imagery below combines the ‘clean window’ Band 13 channel on GOES-16 and GOES-17 (10.3 µm on both) with Band 13 on Himawari-8 (10.4 µm) and shows 2019 data at 6-h intervals.

Color-enhanced Window Channel infrared (ABI: 10.3 µm; AHI: 10.4 µm) imagery from 2019 (Click to launch containerized YouTube Vide)