Around 35,000 fans packed into Mt Smart stadium for last night's sold-out show, with a similar crowd expected tonight.
The Californian crooners have vowed to play on "rain or shine", but promoters Frontier Touring said only "as long as it is safe to do so".
With Cyclone Pam forecast to hit New Zealand about 9pm today, organisers have brought the show forward.
"Based on updated weather information the decision has been made to move the Eagles performance time forward to 6pm," Frontier Touring said in a statement.
"The Eagles will perform rain or shine as long as it is safe to do so."
Gates will now open at 4.30pm, with the band taking to the stage at 6pm.
Fans have been warned to come prepared for rain, but umbrellas will not be permitted.
"Wet weather clothing is recommended. Mt Smart Stadium is an outdoor venue and many areas are not under cover," Frontier Touring said.
Meanwhile, Pasifika Festival has kicked off its second day in Hayman Park in south Auckland.
Organisers announced they had teamed up with the Red Cross to raise money for islands affected by Cyclone Pam. Volunteers would be walking around the Pasifika villages throughout the day with collection buckets.
However, Silo Park cancelled today's open-air markets and free dance event due to be held at Auckland's waterfront Wynyard Quarter "due to weather forecasts".
* Eagles fans can check updates on at www.facebook.com/mtsmartstadium and www.facebook.com/frontiertouring
By NZME. News Service
