I'd guess about 35 lbs - maybe a couple/few pounds either way, but certainly between 30 and 40. With medium dogs I've always found 'double weight at 16 weeks' to get in the right neighborhood.
Thanks, that's like 37lbs.My breeder and some dog enthusiasts in that circle also use the 16 week weight multiplied by two (maybe add 5? pounds) for med-large dogs.