CIMSS Satellite Blog

GOES-16 Mid-level Water Vapor (6.9 µm) images, with rawinsonde sites plotted in yellow [click to play animation | MP4]

With a ridge of high pressure in place over the western Atlantic Ocean, GOES-16 (GOES-East) Mid-level Water Vapor (6.9 µm) images (above) indicated the presence of dry air within the middle troposphere off the Southeast US coast on 23 January 2019.

GOES-16 “Red” Visible (0.64 µm) images showed that marine boundary layer stratocumulus clouds covered much of this region of the Atlantic — and due to minimal absorption by mid-tropospheric water vapor, these stratocumulus clouds were also very apparent in the corresponding GOES-16 Near-Infrared “Cirrus” (1.38 µm) images (below).

GOES-16 “Red” Visible (0.64 µm) and Near-Infrared “Cirrus” (1.38 µm) images, with rawinsonde sites plotted in yellow [click to play animation | MP4]

Terra MODIS Visible (0.65 µm) and Near-Infrared “Cirrus” (1.38 µm) images at 1513 UTC (below) also showed a clear signature of the stratocumulus clouds at 1.38 µm.

Terra MODIS Visible (0.65 µm) and Near-Infrared “Cirrus” (1.38 µm) images at 1513 UTC, with rawinsonde sites plotted in yellow [click to enlarge]

Cross sections of GFS90 model fields along Line I-I’ — oriented from Charleston, South Carolina to Bermuda — are shown below. Note the very dry air within the middle troposphere, with Specific Humidity values of less than 0.2 g/kg and Relative Humidity values less than 10% centered around the 500 hPa pressure level.

Cross sections of GFS90 model fields along Line I-I’, from Charleston, South Carolina to Bermuda [click to enlarge]

from CIMSS Satellite Blog http://cimss.ssec.wisc.edu/goes/blog/archives/31455