The 35-year-old former Pompey striker is expected to go straight into the squad for Tuesday night’s visit of leaders Hereford to Privett Park.
Vine begins a second spell at Borough after making seven appearances in 2015.
Assistant manager Louis Bell believes the arrival of the experienced forward will help some of the younger players in the squad.
‘Rowan will give us another experienced option up front,’ he said.
‘I know him from his time at Portsmouth and he is a good lad to have around.
‘His presence will hopefully help pick up the morale of some of the youngsters.
‘It isn’t easy for them because they keep losing games.
‘Time is getting short and we have to start winning if we are to stay up.
‘I have seen enough in the short time I’ve been here to suggest we can do it.
‘Realistically we know it will be tough but I feel we have the ability in the squad to pull it off.’
Borough are bottom of the table – four points behind Dunstable Town with two games in hand.
The two sides were due to meet at the weekend but the game fell victim to the snow.
After Hereford’s visit, high-flying Kettering Town travel to the south coast on Saturday.
Alex Pike’s side will start both games as underdogs and few will expect them to add to their points tally.
Bell added: ‘We have to go out and work as hard as we can.
‘In our situation we need to try to get something from the two games. There is no doubt we will have to massively raise our game.
‘Hereford are expected to bring 300 supporters, so there should be a big crowd.
‘Hopefully that can help us and give everyone a lift.’