As I noted yesterday, we can expect similar weather here in Seoul as we experienced in Washington, D.C., where we lived until earlier this month. The two capital cities are located about the same distance from the Equator, along the 38th parallel north.
We’ll be in for something different this summer, however. That’s when the rains come. On average, Seoul gets about 35 inches of rain during July and August alone. To put that in perspective, our former home city, Austin, receives about the same amount annually. Seoul gets more rain in these months than most major cities in the American West, in fact.
Compare Austin, Seoul and Washington, D.C., in this chart:
The number of days with some rain also spikes a bit during the Seoul summer. Again, compare the cities:
Cities with similar climates: Seoul, Niigata, Kanazawa, Iwaki, Toyama, Rize, Fukui, Nagaoka, Gangneung, Takaoka, Valdivia, Batumi, Lower Hutt, Sakata
Source: http://www.vividmaps.com/2017/06/find-cities-with-similar-climate.html