No abstract

Adverse weather conditions are known to be one of the main contributing factors affecting traffic operation and safety. Inclement weather conditions impede drivers' ability to perceive and react to their environment, and this decrease in driver performance has a dramatic impact on network-wide operations and the predictability of traffic flow. Studies have shown that drivers may reduce their speed, maintain a larger headway, and drive more carefully in adverse conditions to compensate for reduced visibility and slippery road conditions (1). A previous study investigated the impact of rain on freeway capacity, revealing that wet pavement and decreased visibility affects drivers' speed selection and roadway capacity (2). Although this study focused on the impact of heavy rain, other studies have shown that light rain can also affect travel speed and roadway capacity (3,4). A study by Kyte et al. showed that both light rain and snow can reduce speed up to 50% (5). In addition, the study identified a 9 km/h speed reduction during wind speeds >48 km/h; however, the impact of reduced visibility on speed reduction was found to be marginal. Another study using the same test sites revealed that snow caused a speed reduction of 18 km/h (6). Ibrahim and Hall investigated the difference in traffic conditions during light rain, heavy rain, and snow compared with matching trips in clear weather conditions using the data from two rainy, two snowy, and six clear weather days. Results indicated a 3-5% speed reduction during light rain and snow, a 758035T RRXXX10.

No abstract