木村：この2−3日、急に冷え込んできましたね。
佐藤：本当に。残業して夜中に帰ると、寒さが身にしみますよ。
Mi ni shimiru
Kimura: Kono ni, san-nichi, kyuu ni hiekonde kimashita ne.
Satoo: Hontoo ni. Zangyo shite yonaka ni kaeru to, samusa ga mini shimimasuyo.
Kimura: It's really started to get cold over the last two or three days, hasn't it?
Sato: Yes, I know. When you go home late at night after doing overtime, the cold cuts right through you.
Mi ni shimiru means to feel somthing very strongly or deeply, with all your heart. In this context, mi means somthing like "soul." The verb, shimiru, can be used in other contexts such as, for example, when tending a grazed knee, kusuri ga shimiru (the ointment stings), or when you have a bad tooth and you eat something cold, ha ni shimiru (it makes your teeth ache).
On the other hand, when you're feeling lonely, hito no shinsetsu ga mi ni shimimasu (people's acts of kindness are really touching). Some time ago, whenever I passed through lidabashi subway station in Tokyo, I couldn't help noticing a homeless old man who was always there, and I noticed the box lunch he sometimes had there with him. One day I stopped to give him a mandarin orange to eat with his meal, and he said: Arigatoo. Kooiu toki wa, hito no shinsetsu ga mi ni shimimasu (Thank you. It's at times like this when you really appreciate people's kindness). Since then he has disappeared from lidabashi station, and I often wonder where he is now.
The expression sabishisa ga mi ni shimiru (sadness cuts right through you) can be used in contexts similar to the one above. An expression like kowasa ga mi ni shimiru (to be given a real fright), on the other had, might be used in the context of, say, a Hitchcock film, but is not so common in our everyday lives. In my case, however, after I was involved in a traffic accident,
Kowasa ga mi ni shimite, shibaraku wa unten dekinakatta (I was given such a fright that I couldn't bring myself to drive again for a while).
Samusa ga mi ni shimiru kisetsu desu (The cold is realty piercing at this time of year). I think I'll make something nice and warm for dinner!