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Analysis and Modeling of An Extremely Dense Fog Event In Southern Ontario


In this study, a dense fog episode that occurred near Windsor, Ontario, Canada, on 3 September 1999 is investigated. The fog patch, with a spatial scale of several kilometers, reduced visibility on a major highway to a few meters and led to a series of collisions and loss of life. Satellite imager y and surface obser vations are used to analyze the physics of the event, and several hypotheses on the origin of the fog are presented. A series of simulations of the event with the ?fth-generation Pennsylvania State University–National Center for Atmo- spheric Research Mesoscale Model (MM5) suggest that the fog formed because of convergence of land breezes developing along the shores of a lake and subsequent advection of moisture over the site of the accident. Tests indicate that the small scale of the modeled event contributes to sensitivity of the results to a broad range of factors. Sensitivity to the initial and boundar y conditions, including initial soil moisture content and parame- terization of turbulence, is discussed.

Article / Publication Data
Available Metadata
Fiscal Year
Publication Name
Journal of Applied Meteorology
Published On
January 01, 2004
Print Volume
Print Number


Not available


Authors who have authored or contributed to this publication.

  • Mariusz Pagowski - Not Positioned Gsl
    Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder
    NOAA/Global Systems Laboratory