01126807

Component

Although it is clear that adverse weather has an impact on roadway operating conditions, New Jersey had not performed research to quantify these impacts. To investigate the impact of adverse weather on New Jersey roadways, data on traffic parameters were collected under a variety of weather and light conditions. Speed, flow and density data were collected under no adverse weather, as well as under rain, snow, darkness and sun glare conditions. Comparisons were then made between traffic parameters under no adverse weather conditions, and under each weather and light condition. The study found that under rain conditions speeds decreased between 0.82 mi/hr (11%, 1.3 km/hr) and 37 mi/hr (61%, 59.2 km/hr). Under snow conditions speeds decrease between 5.8 mi/hr (15%, 9.3 km/hr) to 33.8 mi/hr (50%, 54 km/hr). Under rain and darkness conditions speeds were observed to both decrease from 0.71 mi/hr (1%, 1.1 km/hr) to 5.2 mi/hr (7%, 8.3 km/hr) and to also increase. Under snow and darkness conditions, speeds also increased at two locations with a significant decrease in speed of 19.8 mi/hr (33%, 31.7 km/hr) at another location. Under sun glare, speeds reduced from 6.6 mi/hr (10.6 km/hr) to 20.6 mi/hr (32.9 km/hr) showing that the sun glare impact can be as significant as the rain and snow impact. The study found that wet roadways or snow covered roadways had a greater impact on traffic conditions, than the intensity of the rain or snow. The rain and snow impact was seen to decrease as the average speed on the roadway under normal conditions increased.

01120148

09-2837

English

25p

2009

Transportation Research Board 88th Annual Meeting

DVD

Figures (1) ; References (17) ; Tables (9)

Darkness; Environment; Rain; Snow; Traffic data; Traffic flow; Traffic speed; Weather conditions

New Jersey

Environment; Highways; Operations and Traffic Management; I15: Environment

Transportation Research Board Annual Meeting 2009 Paper #09-2837

TRIS, TRB

Jan 30 2009 7:12PM