Twenty-two Jetstar, Qantas, Virgin and Air Asia flights have been affected between Thursday night and Friday morning.
"Based on the meteorology agency prediction, the volcanic ash will reach the airport on Friday morning", airport spokesman Yanus Suprayogi said in a statement, adding that a possible extension of the airport closure after 7pm would be reviewed.
Airlines cancelled mostly global flights after the closure on Thursday, affecting more than 8000 passengers affected.
"Micro tremors are still being detected. indicating that magma is moving towards the surface", Sutopo Purwo Nugroho of the disaster mitigation agency said.
Ash is risky for planes because it makes runways slippery and can be sucked into their engines.
The fresh activity threatens to create travel chaos after Mount Agung eruption in November stranded thousands and pounded Bali's lucrative tourism industry and wider economy.
Two other nearby airports in East Java will remain closed until 5pm (1900 AEST) local time.
Most travel insurance policies for Bali have excluded any volcano-related incidents since it began erupting previous year, as it is considered a known risk.
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Mnangagwa told state broadcaster ZBC, without elaborating, that those responsible must have come from "outside Bulawayo". Mnangagwa, who was rushed away from the scene of the explosion, later visited the injured in hospital.
Tens of thousands of locals fled to evacuation centres after last year's eruption.
Air New Zealand said flight NZ245 from Auckland to Denpasar and the return flight NZ246 from Denpasar to Auckland have been cancelled today.
Authorities were monitoring conditions, but the alert level on the volcano had not been raised so far.
The crater has been erupting periodically since it rumbled back to life previous year.
A 4km exclusion area remains around Mount Agung.
The 3031-metre high volcano's last deadly eruptions occurred in 1963 and 1964, during which about 1200 people were killed.
Indonesia, an archipelago of more than 250 million people, sits on the Pacific "Ring of Fire" and is prone to earthquakes and volcanic eruptions.