Most people run 10/30 everywhere, not sure on NH but Bobcat recommends changing chain oil at 1000 hours.
Local NH dealer in Canada tells me to rum 0/40 sythetic in the engine year around.
I know they don't like 10/30 when its minus 20 out. It takes to long for the oil pressure to ativated the oil pressure sender and the machne goes into shutdown mode. But if yu in the central or southern US 10/30 would work fine.
Mine is the same engine except no turbo