The Climatology, Frequency, and Distribution of Cold Season Fog Events in Northern Utah.

The distribution and frequency of fog events during the cold season in northern Utah is studied using surface Mesowest data from 2004 to 2014. Fog is identified using the reported weather conditions, relative humidity, and visibility. The length and time of each fog occurrence is calculated. Statistics are performed on daily, monthly and seasonal timescales. In order to ensure representativeness of the data and to account for the small sample size available, ‘near fog' conditions are accounted for in some statistics. Results show that there is significant variability among the valleys in northern Utah in terms of both quantity and timing of fog events. However, a distinct peak in fog occurs in late January at all stations.

In addition, the influence of local, mesoscale conditions on the fog distribution are evident in many stations. The controlling factors that contribute to the variability of fog events over northern Utah (a mountainous region) are being investigated. Results will be presented during the conference.