The striker scored twice in a reserve-team clash against Colchester before Christmas, which prompted Steve Tilson to offer him a permanent deal.
And the former Everton trainee told the club's official website: "I'm really pleased to be here. My agent spoke to Southend's chief scout to arrange me coming down for the reserve game and I thought that went quite well.
"After that I stayed and trained with the team for a while and soon after that I found out that they wanted to sort something out until the end of the season.
"I'm delighted to have got this opportunity and I'm determined to try and make the most of it."