Table 2: Traffic flow characteristics of expressway under various weather conditions.

Time periodMorning peakEvening peakOff-peak
Weather conditionHeavy snowNormal weatherHeavy snowNormal weatherHeavy snowNormal weather

Average speed (km/h)56.6054.9659.8446.0564.3671.71
Volume per hour (veh./h)16324722137849528322751
Speed change on heavy snowy day (%) −10.26
Volume reduction (%) 65.44 72.17 69.76