Very temperate where I live, but my bizzarro commute is one of altitude change.
To work: Descending most of the way hitting 40mph in some places, 4.8miles in 13 minutes, usually.
Back home: ~6mph sweaty crawl in about 45minutes.
Perfect commuting weather for me would be 70 degrees at 7am, then cooling down to 40 at 5pm. hasn't happened yet