  We study a class of traffic flow models with nonlocal look-ahead
interactions. The global regularity of solutions depend on the initial data. We
obtain sharp critical threshold conditions that distinguish the initial data
into a trichotomy: subcritical initial conditions lead to global smooth
solutions, while two types of supercritical initial conditions lead to two
kinds of finite time shock formations. The existence of non-trivial subcritical
initial data indicates that the nonlocal look-ahead interactions can help avoid
shock formations, and hence prevent the creation of traffic jams.
