Undular bore over Texas

March 18th, 2016 |

GOES-15 Visible (0.63 µm) images with surface plots [click to play animation]

GOES-15 Visible (0.63 µm) images with surface plots [click to play animation]

GOES-15 (GOES-West) Visible (0.63 µm) images (above) showed the wave clouds associated with an undular bore moving southeastward across Texas during the day on 18 March 2016. The leading undular bore (and packet of solitary waves behind it) were propagating ahead of the advancing cold front (reference).

A nighttime Suomi NPP VIIRS Day/Night Band image at 0814 UTC or 3:14 am local time (below) showed the early stage of bore wave cloud formation over the Texas Panhandle. Due to ample illumination from the Moon (in the Waxing Gibbous phase, at 78%  of Full), this example illustrated the “visible image at night” capability of the Day/Night Band.

Suomi NPP VIIRS Day/Night Band (0.7 µm) image [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) image [click to enlarge]

CLAVR-x POES AVHRR Cloud Top Temperature and Cloud Top Height products (below) indicated values of around +6º C and 2 km, respectively, for the undular bore wave cloud features ahead of the cold front at 1714 UTC.

POES AVHRR Cloud Top Temperature and Cloud Height products [click to enlarge]

POES AVHRR Cloud Top Temperature and Cloud Height products [click to enlarge]

The 2 km cloud top height was consistent with the depth of the stable layers seen above the surface seen in rawinsonde data profiles at Midland (KMAF) and Forth Worth (KFWD), 2 locations which were ahead of the cold frontal boundary at 1200 UTC.

Midland (KMAF) and Fort Worth (KFWD) rawinsonde data profiles at 1200 UTC [click to enlarge]

Midland (KMAF) and Fort Worth (KFWD) rawinsonde data profiles at 1200 UTC [click to enlarge]

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