Cape Newenham, Alaska bow shock waves

June 10th, 2018 |

GOES-15 Visible (0.63 µm) images, with hourly plots of wind barbs [click to play animation]

GOES-15 Visible (0.63 µm) images, with hourly plots of wind barbs [click to play animation]

GOES-15 (GOES-West) Visible (0.63 µm) images (above) showed patches of fog and low stratus moving southwestward off Southwest Alaska and across the adjacent offshore waters of the Bering Sea on 10 June 2018.

A closer look using 250-meter resolution Terra/Aqua MODIS and 375-meter resolution Suomi NPP VIIRS true-color Red-Green-Blue (RGB) images from RealEarth (below) revealed a packet of “bow shock waves” created as the shallow fog/stratus interacted with the relatively rugged terrain of the narrow Cape Newenham land feature (Google Maps). Other examples of similar bow shock wave cloud features have been documented here, here and here.

Terra MODIS, Aqua MODIS and Suomi NPP VIIRS true-color RGB images [click to enlarge]

Terra MODIS, Aqua MODIS and Suomi NPP VIIRS true-color RGB images [click to enlarge]

A 30-meter resolution Landsat-8 false-color RGB image (below) provided a more detailed view of the bow shock wave structure. Snow cover (cyan) could be seen on some of the higher-elevation land features.

Landsat-8 false-color RGB image [click to enlarge]

Landsat-8 false-color RGB image [click to enlarge]

A time series plot of Cape Newenham surface observations (below) showed the fluctuations in visibility as northerly winds brought patches of fog over the site.

Time series plot of Cape Newenham surface observations [click to enlarge]

Time series plot of Cape Newenham surface observations [click to enlarge]

Eruption of the Fuego volcano in Guatemala

June 3rd, 2018 |

GOES-16 Visible (0.64 µm, left) and Infrared (10.3 µm, right) images, with hourly plots of surface reports {click to play animation]

GOES-16 “Red” Visible (0.64 µm, left) and “Clean” Infrared Window (10.3 µm, right) images, with hourly plots of surface reports [click to play MP4 animation]

GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (above) showed that an explosive eruption of the Fuego volcano in Guatemala occurred just after 18 UTC on 03 June 2018. The height of the ash was estimated to be 50,000 feet.

The tan to light brown color of the ash cloud was evident on GOES-16 true-color Red-Green-Blue (RGB) images, as viewed using RealEarth (below).

GOES-16 true-color RGB images [click to play animation]

GOES-16 true-color RGB images [click to play animation]

On GOES-16 Shortwave Infrared (3.9 µm) imagery (below), note the appearance of a persistent thermal anomaly or “hot spot” at the summit of Fuego for about 5 hours prior to the explosive eruption. This thermal anomaly became apparent around 1300 UTC, after which time a low-level volcanic plume could be seen drifting northward.

GOES-16

GOES-16 “Red” Visible (0.64 µm, left) and Shortwave Infrared (3.9 µm, right) images, with hourly plots of surface observations [click to play MP4 animation]

GOES-16 Shortwave Infrared (3.9 µm) images [click to play MP4 animation]

GOES-16 Shortwave Infrared (3.9 µm) images [click to play MP4 animation]

16-panel composite of all ABI bands [click to play MP4 animation]

16-panel composite of all ABI bands [click to play MP4 animation]

 

Minor explosive eruption of Kilauea in Hawai’i

May 19th, 2018 |

Himawari-8 Ash Cloud Height product {click to play animation]

Himawari-8 Ash Cloud Height product [click to play animation]

An explosive eruption from the Halema’uma’u crater at the Kilauea summit on the Big Island of Hawai’i occurred around 1550 UTC on 19 May 2018. Using Himawari-8 data, multispectral retrievals of parameters such as Ash Cloud Height (above) and Ash Loading (below) from the NOAA/CIMSS Volcanic Cloud Monitoring site helped to characterize the volcanic ash plume.

Himawari-8 Ash Loading product [click to play animation]

Himawari-8 Ash Loading product [click to play animation]

Later in the day, a Suomi NPP VIIRS True-color Red-Green-Blue (RGB) image viewed using RealEarth (below) showed the hazy signature of volcanic smog or “vog” which had spread out to the south, southwest and west of the Big Island. Light amounts of ash fall were reported downwind of Kilauea.

Suomi NPP VIIRS True-color RGB image [click to enlarge]

Suomi NPP VIIRS True-color RGB image [click to enlarge]

Subtropical cyclone formation off the coast of Chile

May 9th, 2018 |

GOES-16

GOES-16 “Clean” Infrared Window (10.3 µm) images, with hourly plots of surface weather [click to play MP4 animation]

A very unusual subtropical cyclone formed off the coast of Chile during the 07-08 May 2018 period (Weather Channel | Weather Underground). The system transitioned from a typical cold core baroclinic mid-latitude cyclone to a shallow warm core cyclone with some deep convection around the center of circulation. GOES-16 (GOES-East) “Clean” Infrared Window (10.3 µm) images (above) showed the evolution from 06 May to 09 May. The surface report plotted in the lower right corner of the images is Concepción, Chile.

A Suomi NPP VIIRS True-color Red-Green-Blue (RGB) image viewed using RealEarth (below) depicted the circulation once it had drifted to a position northwest of Santiago, Chile at 1839 UTC on 08 May.

Suomi NPP VIIRS Ttue-color RGB image [click to enlarge]

Suomi NPP VIIRS Ttue-color RGB image [click to enlarge]

The hourly MIMIC Total Precipitable Water product (below) initially showed a long ribbon of subtropical moisture which was being transported ahead of a cold front into the baroclinic low on 05 May — then during the transition to a subtropical low, a small pocket of modest TPW migrated slowly northward  with the surface circulation.

MIMIC Total Precipitable Water product [click to play animation | MP4]

MIMIC Total Precipitable Water product [click to play animation | MP4]