They departed Juanda International Airport in Indonesia's East Java early that morning, but amid increasingly bad weather one of the pilots requested to deviate from their planned route, AirAsia said in a statement.
Although little is known about the aircraft's disappearance
, the region has been struck by torrential rain -- which has some speculating that inclement weather could have played a role in the flight's disappearance
The plane was still traceable about five minutes before it disappeared, according to Indonesian state media. One minute before it lost contact, the pilot requested to raise the plane's flying altitude due to bad weather.
CNN meteorologist Karen Maginnis says that this maneuver could have been made in order to avoid turbulence.
"Turbulence doesn't bring an aircraft down," Maginnis said. "It may be a pilot reaction to the turbulence. It may be perhaps it got too close to a thunderstorm. There could be so many variables."
It's unclear where the diversion took place, but CNN's aviation expert Richard Quest says that's where investigators' attention should focus.
"Bad weather per se does not bring down aircraft," he said. "How the pilot may respond to bad weather could be an issue in this case."
The region has been plagued by heavy rain and severe flooding in recent weeks -- something that the pilots should have been acutely aware of and trained to respond to, according to Maginnis.
"It is typical they would encounter monsoon weather," Maginnis said. "They (the pilots) would have had monsoon training."
With around 8,000 flying hours between them, the pilots could be considered "moderately experienced," Quest said.
Tony Fernandes, the CEO and founder of AirAsia, told CNN's Andrew Stevens that the captain had 20,000 hours of flying experience, 7,000 of which were with AirAsia on the same model of plane that disappeared.
Mary Schiavo, CNN aviation analyst and former inspector general of the U.S. Department of Transportation, said weather can change quickly and there may have been little time to act.
"This weather system might have built up very quickly and they're on their own up there. With the weather up to 52,000 feet, and the operation ceiling is up to about 40,000 on this plane, so they might not have had many options," she said.
Search and rescue
The plane was flying through Indonesian-monitored airspace -- or Indonesia's flight information region -- when contact was lost, according to AirAsia.
Several hours after it disappeared, Malaysia's Ministry of Transport confirmed the Indonesian government had started a search and rescue mission for the missing plane.
"They need to be searching the water but not necessarily for a plane, they need to be searching for any clues," Schiavo said.
The flight's original flight path, a journey of 1,362 kilometers (846 miles), took it over the Java Sea.
And while the search won't cover as large an area as that of MH370, the Malaysia Airlines flight that disappeared in March, it is still a "broad area," which will be affected by weather, according to Maginnis.