The Meteorological Modulators: Quantifying Weather’s Influence on Activity-Travel Behavior

Abstract This study presents an analysis of the effects of weather conditions on travel demand. It develops a combined database of travel demand and monthly, daily and hourly weather conditions. The trip information of the database was extracted from the 2018-19 CMAP Household Travel Survey. To obtain the weather information, the study selected U.S. Local Climatological Data (LCD) data from National Centers for Environmental Information (NCEI) of NOAA. This study examines the effects of a comprehensive set of weather metrics on activity-travel patterns, focusing on activity participation and mode choice behavior. Descriptive analyses of daily and hourly weather conditions and travel demand provide insights into how activity-travel behavior varies with changing weather. The empirical analysis exclusively models the impacts of multiple hourly weather variables and their interactions with demographic and built environment characteristics using a mixed logit modeling framework. Elasticity analysis is employed to assess the magnitude of weather-related effects. Results indicate that temperature, relative humidity, windspeed and visibility strongly influence activity-travel behavior, particularly discretionary activity participation and active mode choices, whereas participation in mandatory activity and choice of single-occupancy vehicles are found to be less sensitive. Overall, the findings demonstrate weather conditions as critical factors influencing travel behavior and emphasize the importance of explicitly incorporating weather effects into travel demand models. These insights reinforce the need for dynamic travel demand models that incorporate real-time or hourly weather data, and underscore the importance of tailoring transportation policies and infrastructure to support resilient transportation systems.