Severe weather prompts Test Site emergency call

Friday, April 29, 2005 | 9:38 a.m.

The end of April brought showers to the Las Vegas Valley and severe weather, including hail and funnel clouds to the Nevada Test Site and to Yucca Mountain, site of a proposed high-level nuclear waste repository.

The National Nuclear Security Administration declared an operational emergency at the Test Site, 65 miles northwest of Las Vegas, about 2:30 p.m. Thursday, NNSA spokeswoman Lee Ann Inadomi said.

A total of 1,200 Test Site workers sought shelter from funnel clouds, hail and severe lightning at the Test Site, she said.

Two buses containing 70 children visiting the Test Site for "Take Your Daughters and Sons to Work Day" had to be sheltered inside a security guard building operated by Wackenhut Services, Inc., Inadomi said. Wackenhut is contracted by the National Nuclear Security Administration to guard the site.

No injuries were reported among the children or the workers, she said.

The children and workers were sheltered in place until the storm moved north and northeast of the Test Site, she said.

Declaring an operational emergency at the Test Site is a rare event, Inadomi said. "I can't recall another declaration," she said.

Inadomi did not have a child with her for the special day, but a co-worker said her son told her he was afraid he would be bored going on Thursday's trip to the Test Site where above- and below-ground nuclear weapons experiments were conducted from 1951 until 1992.

"Not anymore," Inadomi said.

Two funnel clouds were spotted, one hovering over Mercury, the base camp at the Test Site where workers slept and ate during nuclear weapons testing, and the other over Yucca Mountain, the proposed site of a national high-level nuclear waste repository.

The funnel clouds did not become tornados, because they did not reach the ground, National Weather Service meteorologist Jon Adair said.

It was "definitely" rare to see tornados in Southern Nevada, especially at the Test Site, Adair said.

"We got a report of the storm after the funnel lifted back into the cloud," Adair said of the swirling formation that appeared near Yucca Mountain.

The Weather Service issued an advisory about the severe storm at 2:19 p.m. "We watched the storm, but did not see any further cyclonic activity," Adair said.

Those storm clouds scooted over Mesquite and into southern Utah and northwestern Arizona.

In a Test Site environmental impact statement, scientists said that tornados are not considered a "significant event" for the area and the chance of a tornado striking a point on the Test Site is "extremely low," an estimated three twisters in 10 million years.

There have been recorded tornados in the Las Vegas Valley.

In March 1993 the Weather Service reported five active tornados swirling in the Las Vegas Valley in an unusually vigorous spring storm. No one was killed at that time, but a Henderson man was injured when the roof blew off his house.

However, on Sept. 17, 1961, nine people were killed when a massive storm swept the Las Vegas Valley. Although electricity was knocked out throughout the area, weather forecasters believed the storm included a tornado. Four Nevada Power Company repairmen and five Boy Scouts camping in Zion National Park in Utah were killed in the storm.

While no funnel clouds were reported over Las Vegas on Thursday, rainfall reached 0.03 of an inch at McCarran International Airport, the National Weather Service official site for record-keeping.

That brings the 2005 rainfall total to 5.05 inches, Adair said Thursday. The total rainfall between Jan. 1 and Wednesday measured 5.02 inches. Normal rainfall in Southern Nevada for an entire year is 4.45 inches.

The weather will continue to be unsettled. Temperatures are expected to warm into the 70s over the weekend with another chance of rain late Sunday into Monday.