April is among the cruelest natural-disaster months in Hawaii history, with a deadly tsunami striking the islands in 1946 that caused 159 deaths.

A tsunami caused by an earthquake can occur any time, so it is important to be prepared to move to higher ground, said government officials who gathered Friday on Ford Island to announce Tsunami Awareness Month.

"There’s no season for tsunami. They can happen … day or night, good weather or bad, so we have to react to them," said Charles "Chip" McCreery, director of the Pacific Tsunami Warning Center. "Don’t be complacent about tsunamis in Hawaii. Have a plan."

Melvin Kaku, director of the city’s Department of Emergency Management, said that in the event of a local earthquake, people near the ocean should seek higher ground as an initial precaution. A severe earthquake in Hawaii might generate a tsunami that could reach shore in 10 to 15 minutes, Kaku said.

In Waikiki and downtown Hono­lulu, residents and visitors have been advised to do a "vertical evacuation" and go to at least the third floor of any high-rise building.

"If you can, get to the sixth floor," Kaku said. "The structure itself will be able to sustain the power of the waves."

There was no tsunami warning system in Hawaii in 1946, and the officials noted that people unaware of the danger went down to the ocean as the water receded.

The April 1 tsunami was generated by an earthquake in the Aleutian Islands, and houses were washed across the street fronting Hilo Bay. Waters off Hawaii island were dotted with debris and bodies, according to the National Oceanic and Atmospheric Administration.

The tsunami warning center, established in 1949, has expanded into the Pacific Tsunami Warning Center — tracking tsunamis in the Pacific region.

The center, which was for decades located in Ewa Beach, is relocating to the third floor of the new NOAA Ino­uye Regional Center on Ford Island.