Thursday, July 10, 2008 | 4:56 p.m.
The National Weather Service has issued a severe thunderstorm watch today until 10 p.m.
The watch area includes Southern Nevada, northwestern Arizona and southeastern California, primarily the area south and east of Interstate 15, weather service forecasters say.
Isolated thunderstorms formed south of Las Vegas and over the Spring Mountains west of Las Vegas this afternoon.
While forecasters say the severe weather is expected south of Las Vegas tonight, they also say there is a chance of a storm moving into the area.
The storms result as a pulse of moist air from the Gulf of California surges from the southeast of Las Vegas into the southwest, normally at this time of year.
Temperatures normally drop into the 90s or lower 100s with storms that can produce lightning, thunder, hail, wind and an inch or more of rain, the weather service said.
Chances for thunderstorms in the Las Vegas Valley increase this weekend as the moisture continues to stream into the area.