From the experts:
Lowell is an upstanding and somewhat conservative name that calls to mind the genteel patrician families of nineteenth century New England, such as the one poet Robert Lowell was born into. Two other Lowell-surnamed poets are Amy and James Russell.
Lowell was at its height in the 1930s, when it reached Number 148, and has been off the list since 1986--long enough to deserve a reappraisal.
Namesakes include Governor Lowell P. Weicker of Connecticut and noted newsman Lowell Thomas; on TV Lowells have been featured on Wings and Sons of Anarchy.
An interesting British upper-class spelling is Loel.