Transverse banding: a signature of potential turbulence

July 20th, 2016 |

GOES-13 Infrared Window (10.7 um) images, pilot reports of turbulence, Turbulence AIRMET boundaries [click to play animation]

GOES-13 Infrared Window (10.7 um) images, pilot reports of turbulence, Turbulence AIRMET boundaries [click to play animation]

GOES-13 (GOES-East) Infrared Window (10.7 µm) images (above) showed the formation of tendrils of transverse banding along the northern semicircle of  decaying mesoscale convective systems as they moved eastward across Nebraska and Iowa on 19 July 2016. Pilot reports of turbulence are plotted on the images, along with Turbulence AIRMET polygons issued at 0800 UTC and 1400 UTC. Most of the pilot reports of turbulence were in the Light to Moderate category, although there was one report of Moderate to Severe intensity at 1612 UTC over eastern Iowa.

The corresponding GOES-13 Water Vapor (6.5 µm) images (below) perhaps highlighted the transverse banding features a bit better at times, since the weighting function for that spectral band generally peaks in the middle to upper troposphere where the transverse banding cloud features existed.

GOES-13 Water Vapor (6.5 um) images, pilot reports of turbulence, Turbulence AIRMET boundaries [click to play animation]

GOES-13 Water Vapor (6.5 um) images, pilot reports of turbulence, Turbulence AIRMET boundaries [click to play animation]

A sequence of Infrared Window images from POES AVHRR (10.8 µm) and Suomi NPP VIIRS (11.45 µm) (below) showed a higher-resolution view of the initial formation of transverse banding during the 0411 to 1008 UTC time period.

Infrared Window images from POES AVHRR (10.8 µm) and Suomi NPP VIIRS (11.45 µm) [click to enlarge]

Infrared Window images from POES AVHRR (10.8 µm) and Suomi NPP VIIRS (11.45 µm) [click to enlarge]

Shown below are two other types of satellite imagery that can be helpful for identifying the areal extent of transverse banding cloud features: the Suomi NPP VIIRS Day/Night Band (0.7 µm), and the MODIS Cirrus band (1.37 µm). A similar Cirrus band will be part of the ABI instrument on GOES-R.

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]

Terra MODIS Infrared Window (11.0 µm) and Cirrus (1.37 µm) images [click to enlarge]

Terra MODIS Infrared Window (11.0 µm) and Cirrus (1.37 µm) images [click to enlarge]

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