Euan Johnston, 26, was in the driver's seat of a black Audi RS4 estate when he was shot, on Shields Road, near Scotland Street, at 23:45 on Tuesday.
He died a short time later at the Queen Elizabeth University Hospital. A passenger in the car was not injured.
Police said Mr Johnston was shot at multiple times by the occupant of a dark-coloured Audi Q5.
Det Supt Jim Kerr, from Police Scotland's major investigations team, said Mr Johnston, from the Maryhill area of Glasgow, had been for a meal and was travelling home, with one other person in the car, when he was shot at multiple times in a pre-planned attack.
The other person in the car, who was not injured, was being treated as "a significant witness", the detective said.
He also revealed that an Audi Q5 that had been found in the city's Possil area. The officer said the investigation team was "interested" because it was the same kind of vehicle that had been seen driving from the scene.
The lead detective said Mr Johnston, who would have turned 27 next week, was "known to police" and when asked to elaborate, said: "It would be unfair really but we have had dealings with him in the past.
"At the end of the day this is a man going about his night-time business with his friend in the car and he's been shot, and nobody expects something like that."
When asked if the shooting was linked to gangs or drugs, Mr Kerr said: "There could be an association or particular motive but we're keeping our options open at the moment in relation to that."
Describing the shooting, Det Supt Kerr said: "The man had just stopped at a pedestrian crossing on Shields Road, just south of its junction with Scotland Street, when he was approached by the Audi Q5.
"Someone from that vehicle shot him and then the car sped off in a northerly direction on Shields Road and turned east into Scotland Street towards the Kingston Bridge.
"This was obviously a targeted attack. Although it was quite late at night, this can be a busy area and there could have been a number of people walking by or in vehicles."
Det Supt Kerr said no-one else was injured but the shooting had been witnessed by members of the public.
"This is a shocking incident and something that no one should have to witness," he said.
"At this time there is no description of anyone in the suspect car, however, officers are currently checking CCTV in the area in an effort to trace its movements and specialist officers will carry out forensic tests on the car."
The detective said that additional officers were on patrol in the Tradeston and Kinning Park areas of the city, close to where the shooting happened.
He added: "I would urge anyone with information or any concerns at all, to speak to them there.
"A major inquiry has been set up by Greater Glasgow Division and the major investigations team and other specialist resources from across the country."
Police closed Shields Road between St Andrews Drive and Scotland Street for much of Wednesday, and also closed Scotland Street between Shields Road and Carnoustie Street.
Passengers for the subway were not allowed access to the Shields Road station but were permitted to exit the station.
Operators SPT advised passengers to use the West Street, Kinning Park or Bridge Street stations instead.
The multi-storey car park near the station was also closed.

Allen, 25, who joins the Royals on what the club describe as a long-term deal, could make her debut against Arsenal in the Continental Cup on Saturday.
Her Blues debut also came against Arsenal in 2013 in what was an all-English Champions League semi-final.
Allen's arrival comes after Bonnie Harwood left Reading to join Millwall.
A man who was murdered in a late night car shooting in Glasgow was targeted in a pre-planned attack, police have said.
[NEXT_CONCEPT]
Reading have signed midfielder Remi Allen from Women's Super League One rivals Birmingham City for an undisclosed fee.