Is one allowed to take a hair cut tomorrow Friday erev shabbos being that lag beomer is on Sunday?
Answer:
Yes
[Remo"h in Shulchan Aruch, Orach Chaim 493:2]
This is also the view of Maharika”sh (Oholei Yaakov 98), quoted in Yabi’a Omer, (vol. 6, Orach Chaim 47). However, Kaf Hachaim (O.C. 493: note 32) writes that those who follow the opinion of the Mechaber (Sephardim) and do not have a haircut until day 34 of the Omer, may not take a haircut until Monday (this year).