Abstract
Preliminary measurements of several physical and chemical parameters associated with clouds in two cases of onshore flow over western Washington suggest that the physical and chemical properties of maritime, cloudy air passing over this region change over relatively small spatial and temporal scales (∼100–200 km, and 5- 15 h, respectively). These scales are similar to those for changes in precipitation chemistry in this region. This tentative conclusion concerning the scales for air mass changes differs from the assumption usually made concerning air mass characteristics and transport distances in the eastern United States.
