A combination of record-high heat and record-low rainfall has pushed south and central Texas into the region's deepest drought in a half century, with $3.6 billion of crop and livestock losses piling up during the past nine months.

The heat wave has drastically reduced reservoirs and forced about 230 public water systems to declare mandatory water restrictions. Lower levels in lakes and rivers have been a blow to tourism, too, making summer boating, swimming and fishing activities impossible in some places.

"Summed up in one word: devastating," Texas Agriculture Commissioner Todd Staples said.

Nearly 80 of Texas' 254 counties are in "extreme" or "exceptional" drought, the worst possible levels on the U.S. Department of Agriculture's index. Though other states are experiencing drought, no counties in the continental U.S. outside Texas currently register worse than "severe." In late April, the USDA designated 70 Texas counties as primary natural-disaster areas because of drought, above-normal temperatures and associated wildfires.

Texas is the nation's top producer of cattle and cotton and a leading provider of other crops. But many other areas of the U.S. have received normal or above-average rainfall this year, mitigating the potential for more widespread economic fallout as abundant crops elsewhere make up for losses in Texas.

Agriculture-rich California, where crop losses from a severe drought have aggravated the state's deepening budget crisis, has seen normal rainfall in recent months start to ease dry conditions there, a state official said.

In Texas, rainfall levels started declining in the south and central parts of the state in late 2007. The dry weather has been exacerbated this summer by a spell of unusually high temperatures.

The state's worst drought made the record books for its longevity, spanning a seven-year period during the 1950s. This drought, state weather officials say, is more notable for its intensity.

Meteorologists predict relief will come after September, when an El Niño weather pattern of warming currents in the eastern Pacific Ocean is expected to bring up to six months of above-average rainfall.

But by then, farmers and ranchers will have suffered serious economic losses as the drought scorches crops and cattle pastures. Researchers at the AgriLife Extension Service at Texas A&M University say damages are expected to exceed the $4.1 billion in crop and livestock losses the state experienced during a 2006 drought.

Dry pastures won't sustain the usual number of livestock, forcing some ranchers to sell cattle at reduced prices. Jim McAdams, a rancher outside of College Station, said his family's ranch typically runs about 1,200 cows, but is now down to about 800.

"If we don't get rain by early September, it could be trouble," said Mr. McAdams, a past president of the National Cattleman's Beef Association.

Assistance from the federal government should start later this fall, when $3 billion of aid starts flowing from a $290 billion farm bill passed by Congress in 2008. Another federal program that provides money to ranchers who lost calves due to the drought began earlier this month. But Texas leaders have complained the aid isn't coming soon enough, given the severity of the losses.

While Texas bakes, much of the Midwest is experiencing its coolest July on record and expecting bumper crops.

Dan Basse, president of Chicago commodity-forecasting concern AgResource Co., said Monday that he expects U.S. farmers to harvest about 12.4 billion bushels of corn this fall, which would be the second-largest harvest on record. At the same time, U.S. soybean farmers are expected to produce a near-record 3.25 billion bushels.

As Texas aquifers and reservoirs dip to record lows, threatening municipal water supplies, the biggest cities -- Houston, Dallas, Austin, San Antonio -- and 230 others have implemented water restrictions on residents.

San Antonio's water department is encouraging residents to report neighbors if they catch them violating restrictions, and since April more than 1,500 citations have been issued, said department spokesman Greg Flores.

In Central Texas, Lake Travis and Lake Buchanan are down 55% and 49% in volume, respectively. They provide drinking water to more than a million people, including residents of Austin.Additionally, Texas A&M's extension service estimates the drought has caused nearly $100 million in losses related to land-based recreation such as hunting and hiking. At Lake Travis, a popular boating and fishing spot, officials will close the last of the lake's 12 public boat ramps later this week because of the lake's receding waters.

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