noun which may take the genitive case particle 'no'
out of season; unseasonal
Describes something that does not match the current season, such as clothing, food, or weather.
時季外れの暖かさで、コートを着るのが暑く感じた。
With the unseasonal warmth, wearing a coat felt hot.
この果物は時季外れだから、味が落ちるかもしれない。
This fruit is out of season, so it might not taste as good.
More common synonym with the same meaning; 時季外れ is slightly less frequent but interchangeable.
Compound of 時季 (season) and 外れ (deviation, missing).