Crepuscular rays (shadows of distant clouds) cross the sky at Nong Nooch - Thailand's wonderland park south of Pattaya.
Tags: crepuscular rays anticrepuscuar anti-crepuscular all sky rays sky shadows shadows
The pride of any cloud enthusiasts collection: hole punch clouds (recently classified as Cavum) initiated by the passage of aircraft through a layer of super-cooled cirrocumulus cloud. The condensation rapidly develops a virga streak in the center of the hole that grows at the expense of the surrounding cloud. Just the right conditions are required and it helps to have aircraft on distant approach to an airport. The location (Jomtien beach) is on the flight path to Suvanabumi Airport Bangkok. Passing planes on approach are at about 6700 metres. The lapse rate is something like 6.4 degrees C per thousand metres and the surface temperature was 28 C, giving a temperature at the super cooled water droplet cloud layer of about -16 C.
Tags: Cavum holepunch panorama fall streak cloud
Iridescence in recently formed pileus cloud at sunset in Bangkok. A display of this apparent size occurs once or twice a year from a given location. The remarkable colours are photographed with underexposure of the lower cloud.
The intense colours within 20 degrees of the sun are due to diffraction by small relatively uniformly sized water droplets in recently condensed cloud. If the cloud is in a uniform layer a two or three ringed diffraction halo results with a diameter that increases as the droplet size is reduced. The colour patches in pileus clouds (typically towards sunset) are less regular but often show a full range of colours from red to violet. Because the sunlight responsible is often predominantly of longer wavelengths at sunset, reds and yellows often predominate and clear blue as here, and/or violet, are less common.
Iridescence in recently formed pileus cloud at sunset in Bangkok. A display of this nature occurs once or twice a year from a given location. The remarkable colours are photographed with underexposure of the lower cloud.
The intense colours within 20 degrees of the sun are due to diffraction by small relatively uniformly sized water droplets in recently condensed cloud. If the cloud is in a uniform layer a two or three ringed diffraction halo results with a diameter that increases as the droplet size is reduced. The colour patches in pileus clouds (typically towards sunset) are less regular but often show a full range of colours from red to violet (as here upper right). Because the sunlight responsible is often predominantly of longer wavelengths at sunset, reds and yellows often predominate and clear blue or violet as here (center left) are less common.