Domainers too are humans and they need to spend sometime with their family. The reason i am saying this is, there is a general feeling among domainers that, “You can find great deals as it is a long weekend in the US”.
I don’t fully agree with the above statement due to the following reasons
1. Its a vacation only in the US. Domaining is global. Probably you can expect a little lesser competition at the most.
2. Most of the domainers are aware of this and would avoid selling during this time. Chances of you finding great names is not that high.
3. During this time, if you happen to find a domain with less competition, you might get sucked into the thought of having found a great deal while in reality you might have just got a decent deal.
4. From my experience, i hardly find great deals during these vacation times. May be i am not in the right place at the right time. Not sure though.
Good luck for finding deals if you can afford to sacrifice your vacation time but it would be real hard to find any life changing deals imho. I am no way suggesting you not to try but just putting my point across.
Happy vacation and Happy domain hunting. You make your own choice.