The Cottagers head to Jol's former club Tottenham on Sunday lying in a healthy 10th position, but still only nine points above the drop zone.
Stoke, West Ham, Newcastle and Norwich all started the weekend level with Fulham on 33 points and the Dutchman knows any one of them could yet find themselves in trouble.
"We are in a good position but you have to look over your shoulder," said Jol.
"Four or five clubs are still with us there who could be dragged into a situation you won't like.
"We always say we would like to get 40 points as soon as possible and then, you never know. Last year we had 52 points and the year before we were in the top eight with 49, so hopefully we will get 40 and then a bit more."
At White Hart Lane Jol will come up against Gareth Bale, the player he brought to Tottenham from Southampton as a 17-year-old in 2007.
Spurs are being tipped as potential title contenders over the next few seasons and Jol admits the in-form Welshman will be key to their chances
"They were 12 points ahead of Arsenal last season and at the end behind them so they were not consistent enough to contend for the title," he added.
"They are the same as they were the year before, but at some clubs you have the luck of having a player like Bale, making steps and getting better, so that is why they get better."
Mahamadou Diarra should have been the player detailed to stop Bale, but Jol fears the former Real Madrid midfielder may not appear again this season due to a knee injury.
The 31-year-old Mali international has managed just eight appearances this term and will be out of contract in the summer.
"Diarra had an operation, came back, had another little operation but it's still painful," said Jol.
"We will go back to the surgeon and ask for different advice. I think it will be quite complicated without an operation to get him fit again. He will be out for the next couple of months.
"He was the main man last season, one of the most important players. It was a boost for us to get a player of his quality but you need him fit. But he has promised to get fit.
"If someone is not fit you have to assess the situation so hopefully in a couple of months we will sit down with him and make a decision."