This Capital Community College document best describes my dilemma: “When both a city's name and that city's state or country's name are mentioned together, the state or country's name is treated as a parenthetical element.” That’s fine by me; it’s a habit of mine. But I occasionally find myself questioning that “rule.” For example, is the state or country — bookended by commas — a non-restrictive element?
In some cases, this reasoning would check out:
On average, temperatures in Salt Lake City, UT, reach 90 degrees 56 days a year.
There is of course only one Salt Lake City. But when we say something like this,
The tallest building in Portland, ME, is 16 stories tall.
the state element is no longer non-restrictive. If ME is removed from the sentence — as the commas suggest it may be — then most readers will assume the city to be Portland, OR. Other cities’ names come to mind: Springfield, Salem, Washington, etc.
Is the comma following a state or country’s name arbitrary inasmuch as it is applied to each and every state/country (with a few exceptions, each of which can be found in the above-linked document and is not relevant to this discussion)? In many writings — and I assume them to be written by people who do not obsess over the English language as I do — the comma in question is omitted. And this makes sense, especially in instances when the name of state is essential to identifying the city (see my second example).
Should I therefore consider using a comma, always and without discretion; sometimes, at my discretion; or never?
Note that the same is true of dates. For example,
July 4, 1776, is otherwise known as “Independence Day.”
By the same token,
July 4, 2016, is otherwise known as “Independence Day.”