Big Island areas have reached the most intense drought classification, the National Weather Service said.

It marks the first time since the inception of the drought monitor in 1999 that an area in Hawaii has received the D4 designation.

South Kohala and leeward North Kohala are the hardest hit. Less severe drought conditions plague other parts of the state, with only Oahu without areas under a drought classification.

The weather service attributed the dry weather to ongoing El Nino conditions that are producing dry and stable weather conditions through the heart of Hawaii's normal wet season.

“;Several gauges indicated the lowest February rainfall totals since 2000, and most were lower than the January 2010 totals,”; weather service senior hydrologist Kevin Kodama said Thursday.

Conditions on Lanai and over the northeastern slopes of Kauai have worsened, with the areas now considered to be under severe drought — a classification of D2.

Moderate drought, or D1, conditions on Kauai have also spread to the west into the vicinity of the Waimea Canyon area, and the eastern two-thirds of Molokai has also degraded to moderate drought levels.

Extreme drought, or D3, conditions persist over the southern sections of the Big Island, while severe drought also affects Central Maui and portions of the North Kona, South Kona and Kau districts of the Big Island.

In all, more than 75 percent of Hawaii is under at least a moderate drought classification. Hawaii was the only state with D3 and D4 category conditions as of Thursday.

Forecasters are predicting below-normal rainfall for Hawaii through spring.