Foehn wind environment with strong and gusty winds. Explanations of the foehn warming and drying effect in popular literature or on the web often single out just one causal mechanism (#1 - Condensation and Precipitation - in the below), but there are in fact four known causes (illustrated in the schematic at top right of this page). These mechanisms often act together, with their contributions varying depending on the size and shape of the mountain barrier and on the meteorological conditions, for example the upstream wind speed, temperature and humidity. 1) Condensation and precipitation: When air is forced upwards over elevated terrain,
NOAA Weather Radio broadcast routine segment if no report is available from the main reporting station, in which case the substituted station's observations will not be repeated at the end of the segment. In some locales, in the event any weather reporting station (whether the main station or a distant site) whose condition reports are regularly included in the segment had absent data, or no data available, the following message would be played in its place:In some areas, a major city featured within the regional observations would always provide weather conditions; if a condition report is unavailable, the message "the weather conditions were not available"