Winters in Heemstede are cool and occasionally frosty, with temperatures often hovering around freezing point. Spring brings gradual warming, with March and April seeing average highs of 6°C, but still experiencing occasional chilly days. Summers are mild, with July and August averaging around 17°C, while September can be quite pleasant, but October marks the start of a slight cooling trend. Autumn months, from November to December, see temperatures drop again, with winter's chill returning by year's end.