Cloud suck Cloud suck Cloud suck is a phenomenon commonly known in paragliding, hang gliding, and sailplane flying where pilots experience significant lift due to a thermal under the base of cumulus clouds, especially towering cumulus and cumulonimbus. The vertical extent of a cumulus cloud is a good indicator of the strength of lift beneath it, and the potential for cloud suck. Cloud suck most commonly occurs in low pressure weather and in humid conditions. Cloud suck is typically associated with an increase in thermal updraft velocity near cloud base. As a parcel of air lifted in a thermal rises, it also
Cloud cloud of this type is the Morning Glory, a rolling cylindrical cloud that appears unpredictably over the Gulf of Carpentaria in Northern Australia. Associated with a powerful "ripple" in the atmosphere, the cloud may be "surfed" in glider aircraft. More general airmass instability in the troposphere tends to produce clouds of the more freely convective cumulus genus type, whose species are mainly indicators of degrees of atmospheric instability and resultant vertical development of the clouds. A cumulus cloud initially forms in the low level of the troposphere as a cloudlet of the species "humilis" that shows only slight vertical development.