inopportune

Unsuitable for some particular purpose.

That was a most inopportune spot for a picnic.

"It appears I come at an inopportune time, madam," said he, "when my friend, Mr. Rochester, is from home; but I arrive from a very long journey, and I think I may presume so far on old and intimate acquaintance as to install myself here till he returns."

Happening/occurring at an inconvenient or inappropriate time.

The inopportune arrival of the bus cut short the interesting conversation.

The object is to keep the yard operators apprised of main-line movements, so that they do not plan to occupy the main lines with activity into or out of the yard at an inopportune juncture.