seasonably

adverb [时间副词]合时令地；应时地

Un- seasonably warm weather in April and May have helped boost sugar content and overall quality, and consequently prices, of the 2008 watermelons.
今年四五月间，天气异常暖和，也有助于提高今年西瓜的糖分和整体品质，售价自然也水涨船高。