text: what effect do ocean currnets have on boston, ma?   ocean currents have a tempering effect on the climate of boston, ma. in other words, the ocean is warmer than the land in the winter, and colder than the land in the summer. this has the effect of making both the summer and the winter more mild than they are more inland, although the effect is not as strong as on the west coast of the us, because the prevailing winds blow from west to east in the us.  also, because the ocean currents hitting boston, ma are coming from the carribbean ocean, hurricaines occasionally make their way to ma.