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Adverse weather has been shown to be spatially and temporally variable across high‐latitude locations. The current study provides a unique investigation of limited surface visibility time periods at five coastal Greenland locations from 1979 to 2018 and identifies the coincident adverse weather, as well as the local and large‐scale atmospheric conditions during limited surface visibility time periods. Locations on the east coast of Greenland have the largest percentage of hours with limited visibility each month with maxima during February. Western and southern coastal locations have fewer occurrences of limited visibility. Warm‐season maxima are present in the northern locations, while warm‐season minima occur at all other locations. Fog is reported during each month at all five stations, however, a substantial increase of hours occurs at the northern and eastern stations during the typical melt season on Greenland. There is a seasonal difference in the percent of limited visibility hours linked to precipitation with a minimum in the warm season and maximum across the cold season. Limited visibility attributed to precipitation generally has the largest percentage of hours each month except for the northern and eastern locations during the melt season. The location and number of cyclonic circulations, as well as the spatial scale of troughs, across northeastern Canada and the North Atlantic Ocean greatly influence the adverse weather linked to prolonged limited surface visibility events. Limited visibility events at Thule, Greenland during both the warm and cold seasons are largely influenced by the presence and intensity of a cyclone over northeastern Canada. At Danmarkshavn, Greenland limited visibility events in both seasons generally have a cyclone positioned to the east, an area of higher pressure over Greenland and a cyclone positioned to the west of Greenland. [ABSTRACT FROM AUTHOR]

This study investigates the influence of synoptic-scale cold fronts on microclimatic conditions within the complex terrain of Watkins Glen gorge, New York. Temperature and dewpoint temperature measurements were collected by three microclimate stations both within (two stations) and just outside (one station) of the gorge during the months of September and November. A total of nine cold fronts passed over the gorge at different times of day (i.e., daytime, nighttime, and transitional) during the eight-week measurement period. During the prefrontal time periods, the two sites within the gorge were similar in both temperature and moisture content: colder and greater moisture content compared to the outside-gorge site. A stable inversion layer was present at the rim height of the gorge a large percentage of time resulting in limited mixing and a separation of the outside-gorge and inside-gorge atmospheres. Following the passage of cold fronts, there was a robust transition to a large-scale colder atmospheric air mass across the central New York region and introduction of less stable conditions that allowed intrusion and mixing of outside-gorge air within the complex terrain of Watkins Glen gorge, especially during nighttime and transitional cold fronts. [ABSTRACT FROM AUTHOR]