When I took yesterday's weather photo, I was wearing a lightweight sweater and my lightest jacket--a windbreaker. The temperature was in the fifties.
This morning, there were snow flurries on my walk to school, and you can see above what it looked like out my office window around 10:00. It has snowed off and on all day, but hasn't stuck yet. The temp. right now is 27 and falling. If I go outside tonight, I'll have on my heaviest jacket (parka), scarf, gloves, etc.
That's how the weather is in Seoul.