Station Siting, Microclimates, and Their Impacts on the Urban Forecast Challenge

Because surface characteristics can be vastly different between rural and urban areas as well as throughout a city, significant variability exists in the local microclimates observed by meteorological stations deployed in an urban area. In many cases, the observations collected from meteorological stations in urban areas can represent different spatial and temporal scales (a) as the ambient weather conditions change (b) in combination with the specific siting of the station. Thus, documentation of the physical characteristics near any site is critical to fully understand the overall representativeness of the site and the associated evolution of atmospheric conditions within an urban zone.

Using Oklahoma City as an example, this study will demonstrate the importance of station siting and microclimates as related to the forecast challenge in an urban area. Particular focus will include (1) the urban heat island of Oklahoma City, (2) how it is captured by in situ observations, and (3) how it changes in shape, size, and intensity due to changes in larger-scale atmospheric conditions. In addition, the observed conditions will be compared with numerical forecast products to demonstrate the importance of understanding the microclimates of an urban area when utilizing numerical forecast data.