Hot temperatures stay as humidity returns

By Mary Manning

Friday, July 25, 2008 | 6:32 a.m.

Those clouds streaming into the Las Vegas Valley from the southeast this morning are remnants of thunderstorms that fired up over central Arizona Thursday night. They are announcing the return of the Southwest monsoon, the National Weather Service said.

Although thunderstorms are not expected in the Las Vegas Valley until Saturday or Sunday, Laughlin or Lake Mead might see an isolated thunderhead late this afternoon or this evening, the weather service said. The humidity jumped by 28 percent in 24 hours along the Lower Colorado River, forecasters said.

For Saturday and Sunday, as the moist air tries to push that hot, dry dome of high pressure away from the valley, the chance of a thunderstorm improves southeast of Interstate 15, the weather service said.

But what was once Hurricane Dolly, now a tropical rainstorm, is not expected to surge into Southern Nevada, forecasters said this morning. Instead, Dolly's remnants will track due west across northern Mexico and the Gulf of California, if the next three days of weather go according to the unfolding forecast.

Temperatures are expected to reach 108 degrees today, then highs could range from 105 on Saturday to 103 on Sunday, depending on how much cloud cover pushes into the valley.

By Monday and Tuesday Las Vegas could return to drier conditions if all the hot air wins over the moist southeast flow of air, the weather service said.