美國寒潮從華盛頓到波士頓？

今年美國寒潮很多，不經意看到下面的信息：
Across the southeastern U.S. Wednesday, hundreds of thousands lost power in their homes and businesses as a winter storm clobbered the region and prepared to head north along the eastern seaboard to drop inches of snow from Washington to Boston.

地址如下：

好奇怪喔，寒潮不是從北邊 加拿大 那邊來的嗎，怎麼是向北走啦，從 華盛頓到波士頓，奇怪了。

求大神解答。。