Inopportune (adjective)

Not occurring at a convenient or suitable time; untimely.

Origin:

From the latin words in meaning 'not' and opportunus meaning 'opportune'.

Examples:

1. The inopportune rain ruined the outdoor concert.
2. The inopportune call interrupted the important meeting.
3. The inopportune timing of the announcement caused a lot of confusion.
4. The inopportune delay added to the already stressful situation.
5. Inopportune circumstances often make it difficult to accomplish tasks.