Excessive heat warning issued for Las Vegas Valley

By Mary Manning

Wednesday, July 9, 2008 | 10:50 a.m.

The National Weather Service is forecasting 112 degrees for the Las Vegas Valley today, triggering another excessive heat warning from 11 a.m. until 8 p.m.

The record high for today soared to 113 degrees in 1949, according to weather service records.

Records were broken Tuesday with 117 degrees at Needles Airport, tying a record set in 1985, and 113 degrees at Barstow Daggett Airport, tying the 1976 record, the weather service said.

Although the official high temperature reached 111 degrees at McCarran International Airport on Tuesday, meteorologists say a dome of high pressure still dominates the Mojave Desert today through Thursday. The heat will continue through Thursday and then a big change is expected in Southern Nevada.

Late Thursday, a surge of moisture known as the Southwest Monsoon will begin pouring into Southern Nevada from the Lower Colorado River Basin. The winds will shift from southwest to south-southeast, bringing moist air from the Gulf of California, and chances for thunderstorms and flash flooding could occur east and south of Interstate 15 running through Southern Nevada and Southern California as early as Friday, weather service forecasters say.

The arrival of the moisture, which often lowers daytime temperatures in the Las Vegas Valley to the low 100s, is uncertain at this time, weather service meteorologists say.