A more indepth look at "Hump Day" from WiseGeek.com says
Referring to Wednesday as "hump day” is a tradition in American English. It refers to the idea that a week — especially a work week — is like a hill. Monday and Tuesdays are days when you climb up, since they are the beginning or start of your work week. At the end of Wednesday, you’ve reached the pinnacle of the week, and your work on Thursday and Friday represents climbing down toward the weekend.
Hump day then refers specifically to that middle of the week point, where you reach the crest of your journey and begin to pace downward toward the end of the week. If you have a tedious job or just work hard, it can be comforting to reach hump day. Then, the weekend doesn’t seem so far off and nebulous as when you started work on Monday.Wednesday, October 26, 2011 also marks the "hump day" of the 2011 Ernst & Young Corporate Responsibility Fellows Program for TimeIRado. I have been in country for 26 days out of the total 51 days (Leave November 20th), therefore 51% of the way completed.
This is great from the standpoint that I will see get to see family and friends for the Thanksgiving Holiday, but it also means that the time here in the great city of Sao Paulo, Brazil is quickly coming to an end. Stating this fact should also not to be confused with counting down the days until we leave, but more of a celebration of what we have come to know and experience during our time here.The city and companies that have been a huge part of our lives over the past 26 days, have made a huge impact. However, there is still lots of work to be done and experiences to be had!
Good Night Sao Paulo!