The drought -- the worst on record in North Carolina -- became slightly more intense across the state over the past week, according to a report out today.

Gov. Mike Easley announced today that water usage is down 30 percent for the state's 25 largest public water systems, but conservation efforts have fallen short of the governor's goal of 50 percent reduction in water use for the state.

Of North Carolina's 100 counties, 58 are experiencing "exceptional" or "extreme" drought, the most intensive of four categories of drought, according to the U.S. Drought Monitor's weekly report. That's up from 52 counties in those categories last week.

The Triangle counties of Wake, Durham, Orange, Johnston and Chatham are among 33 counties under extreme conditions.

The state is in the grip of the worst drought ever recorded, going back to 1895 when drought conditions were first calculated, according to a separate report this week by the National Weather Service.

Conditions are not likely to improve soon. To ameliorate the drought, the state needs 14 to 18 inches of rain over the next three months and 25 to 30 inches over the next six months, the National Weather Service said.

The probability of that happening? Less than 15 percent.

To completely end the drought this winter, the state needs as much as 24 inches of rain over the next three months. The chances of that occurring are less than 4 percent.

Other findings in the National Weather Service report:

October rain

Benefits from a well-timed rain in late October are wearing off. Central North Carolina got 2 to 5 inches of rain from the October storms, but as of last week, stream flows across the state had dropped significantly. Most are less than 25 percent of their normal levels.

Area lakes

The October rain did not compensate for months of dry weather and long-term water shortages. Falls Lake rose less than one foot, while Jordan Lake and Kerr Scott reservoirs rose 2 to 3 feet. Flows into the reservoirs have fallen below normal in recent days.

Falls Lake

Falls Lake, which supplies drinking water to Raleigh and most of Wake County, is more than 8 feet below normal, and only 36 percent of the lake's water supply remains. Falls Lake does not go dry when its water supply is depleted; the lake will still be 36 feet deep, but the water will be thick with sediment and require additional treatment.

Winter forecast

North Carolina is likely to miss out on large-scale rain and snow needed to end the drought because of La Nina, or cooler than normal sea temperature over the central Pacific Ocean. La Nina weakens the jet stream, which typically brings moisture and storms into the mid-Atlantic during the winter.

Reason for the drought

The drought goes back to the summer, which was the hottest on record across Central North Carolina. The record heat exacerbated the moderate drought conditions that existed in the spring. Since July, precipitation has averaged less than 50 percent of normal over much of the state. By mid-October, nearly 90 percent of the state was experiencing extreme to exceptional drought conditions.

Good news

Cooler weather in the fall and winter means less water loss to evaporation and lower water demand. So any significant rain will help recharge reservoirs.

Bad news

Even a return to near normal rainfall over the next three to six months may not end the drought. If climate predictions come true, we will face ongoing water shortages in the spring and summer.