EWA BEACH, Hawaii -- Tsunami experts at the Pacific Tsunami Warning Center said they came very close to issuing evacuation orders on Wednesday morning after the earthquake near Japan.

Scientists said it was a close call.

"This was the biggest tsunami event to cross the Pacific since the great Alaska quake of 1964," Pacific Tsunami Warning Center director Charles McCreery said.

Scientist said that all of their precise measurement and computer models were not enough to be completely sure about how big of a tsunami could hit.

At about 4:20 a.m., three hours from impact, the scientists consulted state Civil Defense and decided no evacuations were necessary.

"We felt like there probably wasn't going to be a damaging event, but it could've been close to that effect," McCreery said.

The fact that two prior tsunami warnings in 1986 and 1994 had been false alarms did not affect them, officials said.

"We've done a lot of work in the last 10 years to improve our system. That's what gave us the confidence," McCreery said.

While the open ocean tsunami was not very big, officials and residents saw how such a wave event impacts various coastal areas and how it is almost impossible to predict.