Caught between two fronts, Nevadans left out in rain

Friday, Sept. 11, 1998 | 10:44 a.m.

Rain, high winds and afternoon lightning and thunder will keep the Las Vegas Valley soaked until Sunday, the National Weather Service predicts.

Southern Nevada is caught between a low-pressure trough in central California and a high-pressure ridge east of the Rocky Mountains, meteorologist Donald Maker said.

The low-pressure system has stalled over central California, Maker said. As it crouches there, it draws moisture from tropical storm Jabier, which has killed more than 32 people in Mexico. That moisture has soaked Southern Nevada, California, Arizona and Utah for almost a week.

While the Mexican storm has snarled traffic, knocked out power and flooded familiar areas such as the Charleston Underpass here, Jabier has swallowed homes under a torrential downpour and residents along the Pacific Coast have been evacuated.

Meanwhile the high pressure sitting east of Nevada extends from Canada to the Mexican border, Maker said.

"Nothing can move as long as that high-pressure ridge stays put," he said. "We're still looking at a chance of showers and thunderstorms because of the unsettled, unstable conditions through the weekend."

By Sunday the atmosphere should start to move eastward again, shoving the high-pressure system out of the way and moving all the moisture away from the Southwest.

Temperatures are expected to rise into high 90s.

"It's a trade off," Maker said, explaining that once the moisture moves out, drier air will replace it bringing the unseasonably high temperatures.

Drier, warmer temperatures could signal the beginning of a drought expected to grip the Southwest as the tropical Pacific cooling phenomenon known as La Nina arrives.

If La Nina, the cooling half of the cycle that has brought El Nino's warm rains to the Southwest, continues to develop, Southwestern residents will notice a change by November, said Ants Leetmaa, the nation's top meteorologist.

Leetmaa predicted Wednesday that the number and intensity of storms will decline in the Southwest between November and March.

Like El Nino -- and this year has been "El Nino of the Century" -- La Nina disrupts worldwide weather in the winter months. Both extremes are part of a cycle at least 2,000 years old which allows ocean temperatures, rainfall, winds and air pressures to change drastically over the Pacific Ocean near the equator.