Saturday, Oct. 14, 2006 | 8 a.m.
In the middle of the Pacific Ocean, the sun is shining, warming the surface of the sea more than in an average year. Thousands of miles to the east, that warmer-than-average ocean is helping to bring storm systems carrying precious precipitation to California, Nevada and the mountains of the American West.
El Nino has arrived, and with it has come several storms that water officials hope are harbingers of a wet winter. Rain gauges across the Intermountain West, including vital Colorado River sources in the Rocky Mountains, are showing totals for the "water year" as much as 200 percent or more of normal.
Kelly Redmond, regional climatologist with the Desert Research Institute's Western Regional Climate Center in Reno, said the eye-popping totals are not yet statistically significant, since the water year started Oct. 1. But they indicate that there has been a good bit of rain and already some snow, early in the season.
"Normally, we don't expect a whole heck of a lot to be going on yet," Redmond said Thursday, a day before another Pacific storm arrived. "But it is an auspicious start to the season."
Redmond was in the Yosemite area of California a week ago and saw one storm arrive, and the climatologist arrived for a conference here just as the same storm brought measurable precipitation to Las Vegas.
"That was kind of an interesting episode. A cabdriver was even discussing how long it (the rain) seemed to last."
Brian Fuis, a spokesman with the National Weather Service's Las Vegas office, said computer models show Southern Nevada getting as much as a half-inch of rain in the valleys and even some snow high in the mountains from the weather maker that arrived Friday.
That's consistent with the National Oceanic and Atmospheric Administration's outlook for the winter that was released Wednesday, he said. The outlook calls for a milder, wetter winter than average for the southern Rocky Mountains and Colorado River basin.
The outlook is also consistent with what scientists are seeing in the Pacific. Generally, the stronger an El Nino - or warmer-than-average water in the central Pacific Ocean - the more precipitation the southern Colorado River basin can expect. Fuis said federal scientists are forecasting intensification of the existing El Nino over the next two to four months, "which would mean a wetter winter for us."
A strong El Nino in the winter of 1997-98 helped push Lake Mead water levels near the top of Hoover Dam's spillways. Years of drought, however, have sent water levels plummeting and have federal and state officials, including those with the Southern Nevada Water Authority, discussing rules to handle shortages along the Colorado River - source of nearly all of Las Vegas' drinking water.
Even if a much-hoped-for wet winter in the Rockies develops, the river will need time to heal, Water Authority spokesman Scott Huntley said.
"It's going to take a lot of years like that," he said. "It's going to take a lot of snow and a slow snowmelt."
A year ago, local and federal officials had high hopes for another good year. And for a while it seemed to develop - by April, the Bureau of Reclamation estimated that the snowpack was 97 percent of average.
Early spring heat, however, literally evaporated the hopes for a relatively good winter, as the snowmelt returned to the air rather than melting into the ground and springs that feed the river. In the end, the winter provided only 67 percent of average.
Even if the Colorado River basin gets 110 percent of "normal" precipitation, it will take eight years of such winters to return Lake Mead to the levels of June 2000 - the official start to the river's drought, Huntley said.
Redmond said that the factors of temperature, precipitation and El Nino are still being studied. Not all El Nino events will provide good precipitation in the West. The timing, durability, magnitude and specific area of the event all will determine the amount and location of the water, he said.
But for now, there is hope.
"You can hope all you want," he said.
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