unseasonal

unseasonable, unseasonal

Any difference in meaning corresponding to that of the positive forms (see seasonable, seasonal) has become irreparably eroded, and the two words are both used to describe circumstances (especially weather conditions) that are not appropriate to the season in which they occur:

• Younger people, because of the unseasonal heat, were wearing sweaters tied round the hips —James Kirkup, 1991

• The weather looked heavy and thundery, as if the unseasonable warmth would soon break —K. McCallum, 1993.

Unseasonable occasionally means ‘not opportune, untimely’ more generally:

• According to BBC News, ‘North Korea's unseasonable gift to the world was to unleash a new nuclear crisis’ —Spiked Online, BrE 2004 [OEC].