Discussion on defining district borders for Boston is in progress. If you know the city pretty well, please share your opinion on the talk page.
New England is unpredictable and becomes very cold in the winter and is prone to mild bouts of humidity in the summer. The vast majority of tourism in Boston takes place in the summer, from late May through late September, when the weather is ideal and the most attractions are open. Boston summers are quite comfortable, with sunshine 60-65% of the time and and highs in the mid 70s to low 80s F (mid to upper 20s C). When the heat does start, there are some beaches within the city, and many beaches outside of it, for swimming. The Standells classic "Dirty Water" doesn't apply any more as the water is safe to swim in thanks to the Boston Harbor Cleanup project. Beware that no matter how hot it is outside, the ocean water will not be warm. Early and late summer tends to be nice, but this varies by year. In that time, the temperature will be perfect, and there will be no humidity. The city does have unpredictable stretches of heat between late June and early August when low 90s and high humidity are expected. All public transit options, including cabs, buses, and the subway system (called the "T") are air-conditioned.