Brown, who appeared before a Los Angeles County Superior Court judge Monday, must return for a hearing on February 10 that will decide if he'll serve jail time after his three months in rehab.
The singer has an anger-management problem and drug-abuse issues, according to a probation report obtained by CNN.
He's been on felony probation since pleading guilty to beating up singer Rihanna on the eve of the Grammys in 2009.
Judge James Brandlin ordered Brown to check into a rehab program a month ago after he had been booted from another rehab facility a week earlier for smashing his mother's car window during a family session.
A report submitted to the judge by Brown's probation officer included a letter from his current rehab facility saying he "has made significant progress" since starting in the program on November 20.
"The clinical and medical team have witnessed very positive change in Mr. Brown since his psychotropic medications have been changed and he has been taken off medical marijuana," the program director said. "His ability to emotionally regulate himself has improved markedly."
"I'm pleased that he's doing well," Brandlin said Monday, explaining why he did not send him to jail Monday afternoon.
Brown was arrested on an assault charge in Washington on October 27. That case is why Brandlin ruled Monday that he was tentatively revoking Brown's probation for the Rihanna assault. He will decide in February if he will order Brown to complete his sentence in prison instead of probation.
Brown's girlfriend Karrueche Tran accompanied him to the Los Angeles County courtroom Monday. For the second time, his mother was not with him.
Brown's freedom has been in question since he was arrested on a sidewalk near the White House after allegedly punching a man.
The probation imposed when he pleaded guilty to a felony charge in the attack on Rihanna -- his girlfriend at the time -- requires that he stay out of legal trouble.
Brown voluntarily entered a rehab center on October 28, a day after he was released from a Washington jail.
The probation report given to the judge last month revealed that he was kicked out of the program. It quoted a center official saying he was ordered out for "breaking program rules by acting violently."
The violence involved Brown "throwing a rock through his mother's car window" after a family session at the center in which she said she wanted him to stay in treatment.
"Mr. Brown preceded to walk outside and pick up a rock and threw it through his mother's car window and it shattered," according to letter from the rehab center included in the probation report.
Brown's "prognosis is very guarded" unless he gets professional help, the letter said.
Brown leaves the new rehab center three days a week to work eight-hour shifts of community labor so that he can complete the 1,000 hours of work still remaining in his punishment for attacking Rihanna. The report estimated he will have to work on community labor three days of every week until next August to meet the deadline for completing the labor.
He may also travel to Washington for a court hearing on January 8 in the assault case there, the judge said.