Without a HardFork the main prediction here is that the price will skyrocket. In few months Bitcoin can be pricing $4500 or even more.
But seems things won't happen so fast, we need to wait what will happen right after August 1, maybe there will be a delay of days or weeks until things come back to the normal as we see today.
So is the hardfork 100%?
not sure yet but i know now the BIP 141 (proposed by bitcoin core) deadline is missed by the miners but there is another deadline which is in July 29 where the miners must activate segwit by BIP 91 (segwit2x) with lower activation threshold which is 80%. so, there is still a chance to halt the activation of BIP 148. well we wil see that in next few days.