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Tropical Cyclogenesis

Cirrus Clouds

Cirrus clouds (abbreviated Ci) are high clouds consisting of ice crystals attached to dust or other fine particles. Cirrus clouds usually appear thin and wispy, but may be thick, opaque, or not visible (while still blocking radiation).

Figure 1:  Cirrus clouds, high in the sky. [Wiki]

Cirrus clouds may form from the tops of cumulonimbus clouds (thunderstorms), indicating a storm is approaching.

Cirrus clouds could also be the anvil top remnants of cumulonimbus clouds that have dissipated.

Figure 2:  Cirrus cloud forming from dissipated cumulonimbus. [GerritR]

Transverse Cirrus Bands

Transverse Cirrus Bands (TCB) are parallel cirrus clouds that are perpendicular to a long axis which may be radial.

Figure 3:  Transverse Cirrus Bands (TCB), Norway. [Ximonic]

Figure 4:  TCB in the sky. [McPherson]

Figure 5:  Satellite view of TCB in the South Pacific near South America, around 10.23°S  102.68°W and 15.87°S N 98.4°W (click on image to view larger). [NASA Worldview]

Figure 6:  Vertical cut through the atmosphere acquired by a spacecraft radar-like sensor, showing the TCB of preceding figure as high altitude clouds, along a path that includes the marked lat/long positions in the preceding figure (click on this image to view more path). [NASA GSFC]

The preceding two figures, of the same TCB in the South Pacific, were acquired by different remote sensing platforms, on the same day, but not at the same time, so that the clouds have moved (are not quite at the same longitude and latitude positions in both data acquisitions).

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Tropical Cyclogenesis

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Cumulonimbus Clouds
Cirrus Clouds (this page)
Storm Rotation
Eye of the Storm
Jova & Lee 2023

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