Unusually warm Pacific waters have sustained Lane, and Hawaii Governor David Ige is urging tourists to prepare for the worst.
"[Hurricane] Lane will pass dangerously close to the main Hawaiian islands as a hurricane Thursday and Friday", the NWS said.
Hilo Airport has seen almost 15 inches of rain in the same period of time.
How soon it turns and how sharp it turns will determine how close the center gets to the islands and how much damage it will cause.
People have been flocking to stores for supplies.
The Vancouver (YVR) airport also has multiple flights from other airlines to the Hawaiian Islands listed as cancelled.
"We just need to urge people to use common sense", he said.
Camera IconThe storm boasts winds of 250km/h.
The National Weather Service said Lane - located about 320km south of Hawaii - remained a powerful category four hurricane, packing winds in excess of 209kmh.
Citing a report from Consul General Joselito Jimeno, the DFA said a hurricane warning was already hoisted in the Big Island (Hawaii Island) and Maui, while a hurricane watch was in effect for Oahu, where Honolulu and Kauai Island are located. Tropical storm conditions are expected to begin over portions of Maui County later today, with hurricane conditions expected in some areas by Friday.
Steve Goldstein of the National Oceanic and Atmospheric Administration said at a news conference Thursday that Lane had winds up to 130 miles per hour. Both are waiving reservation change fees as the hurricane approaches. A slower hurricane increases the threat of flash floods and landslides because of prolonged rainfall.
The downpours could also lead to landslides. The last major hurricane to hit famously made landfall during the filming of "Jurassic Park" in 1992.
"Heavy rain in Hilo right now", Hawaii County Managing Director Wil Okabe said of the east side town.
The Category 4 storm could bring unsafe surf of 20 feet and a storm surge of up to 4 feet, forecasters said.
It's not yet clear from forecast maps whether Lane will actually make landfall, meaning that its eye wall crosses over land, in Hawaii.
Unlike Florida or Texas, where residents can get in their cars and drive hundreds of miles to safety, people in Hawaii are confined to the islands and can't outrun the powerful winds and driving rain.