Clouds and Visibility
According to the National Transporation Safety Board (NTSB), every year low clouds and visibility directly or indirectly account for the largest number of aircraft accidents, mainly small aircraft. However, low clouds and visibility also impact large aircraft by closing or restricting major airports, causing ground delays.
McCann Aviation Weather Research, Inc. offers VVCLOUD as a cloud forecasting algorithm that incorporates the meteorological variables important to cloud formation. The VVICE icing algorithm has to compute the cloud liquid water (CLW), including the convectively generated CLW, in order to compute aircraft icing potential. Levels at which there is positive CLW are levels of clouds.
Hit the red button at left for a technical description of VVCLOUD.
Conceptually, the meteorological conditions favorable for low visibility and fog are unique and easy to observe. However, today's numerical model forecasts poorly forecast near ground conditions, so they do not reliable forecast these unique conditions for fog. McCann Aviation Weather Research, Inc. is working on alternative techniques.