CIMSS Satellite Blog

Composites of geostationary and polar orbiter Infrared imagery [click to play animation]

Composites of Infrared imagery (above) and Water Vapor imagery (below) from the AMRC site showed an anomalously strong (MSLP | 925 hPa winds | source) cyclone that was moving southeastward across the South Pacific Ocean toward the coast of Antarctica on 26 March 2019. These composites blend images from both geostationary and polar orbiting satellites; the storm is located in the upper right quadrant of the images. On the Infrared imagery, brighter white shades over much of the middle of Antarctica indicated a very cold surface — in fact, surface air temperatures were as cold as -84ºF over the interior of the continent at 23 UTC.

Composites of geostationary and polar orbiter Water Vapor imagery [click to play animation]

The storm was evident along the southern limb of GOES-16 Full Disk scans, as seen on Mid-level Water Vapor (6.9 µm) and “Red” Visible (0.64 µm) images (below). The location of AMRC AWS station 8930 (Thurston Island) near the coast of Ellsworth Land in West Antarctica is indicated in red.

GOES-16 Mid-level Water Vapor (6.9 µm) images [click to play animation | MP4]

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

A time series of surface observation data from AWS station 8930 Thurston Island (below) showed that southeasterly winds increased to 113 knots (58  m/s) as the strong low pressure system moved closer.

Time series of surface observation data from AWS station 8930 Thurston Island [click to enlarge]

A closer look with GOES-16 Visible and Low-level Water Vapor (7.3 µm) images (below) revealed small wave perturbations in the cloud field and the eventual formation of a banner cloud as Peter I Island was acting as an obstacle to the strong boundary layer winds.

GOES-16 “Red” Visible (0.64 µm. left) and Low-level Water Vapor (7.3 µm, right) images [click to play animation | MP4]

A timely overpass of the Landsat-8 satellite provided a 30-meter resolution Landsat-8 False Color RGB image, viewed using RealEarth (below), of these orographically-induced cloud perturbations.

Landsat-8 False Color RGB image [click to enlarge]

The orographic wave clouds could also be seen downwind of Peter I Island in 375-meter resolution Suomi NPP VIIRS True Color RGB and Infrared Window (11.45 µm) images at 19 UTC and 21 UTC (below).

Suomi NPP VIIRS True Color RGB and Infrared Window (11.45 µm) images at 19 UTC and 21 UTC [click to enlarge]

#GOESWest is watching a hurricane-force low that’s headed toward the Antarctic Peninsula. This loop uses what’s known as Air Mass RGB Imagery, which helps distinguish polar from tropical air masses. More imagery: https://t.co/3SWkPqjxr9 pic.twitter.com/nUOKrYtfm1

— NOAA Satellites (@NOAASatellites) March 26, 2019

from CIMSS Satellite Blog http://cimss.ssec.wisc.edu/goes/blog/archives/32608