Wetter monsoon season predicted

Keep alert for flooding, officials in LV Valley say

Southern Nevada’s 2018 monsoon season is expected to be wetter than normal, prompting warnings for residents to be ready for potentially deadly flash flooding.

While a new long-term forecast this week said seasonal rain and thunderstorms in the Southwest are expected to be 40 percent above average during the coming monsoon season, the Las Vegas Valley is likely to receive about a third more rain than usual, National Weather Service meteorologist John Adair said.

The Southwest monsoon season typically runs from early July to mid-september, but it varies depending on weather conditions.

Southern Nevada might see some moisture as soon as the Fourth of July, said Adair, who works in the weather service’s Las Vegas office.

“We’re seeing the possibility of moisture starting to approach northwest Arizona, Southern Nevada as we get into Tuesday, Wednesday next week, which is about normal for Southern Nevada,” he said.

Other than the above-average rainfall expected, it is too early to say much more about the upcoming monsoon season, Adair said.

The thunderstorms are not expected to do much to alleviate the extreme drought conditions gripping a large swath of the Southwest, he said. Southern Nevada is experiencing a moderate drought.

Winter storms tend to bring more widespread precipitation that do more to ease droughts, he said.

“In the monsoon season we get thunderstorms that kind of pop around,” Adair said. “It can help a little bit, especially if we get lots of thunderstorm days, but we really rely on the fall, winter, early spring precipitation.”

But summer thunderstorms, which can be intense in localized areas, frequently trigger flash flood warnings, which are issued when the life-threatening torrents are imminent or already happening, Adair said.

“People just need to be aware of their surroundings” and seek higher ground when flash floods are possible, he said.

The Clark County Regional Flood Control District is in the middle of a project to install drainage tunnels in the northwest valley that should help.

The addition to the flood control network, which will cost more than $20 million, is expected to be completed by December. It is one of 19 flood district projects under construction, about to start construction or out for bidding, totaling nearly $115 million. The district is made up of representatives from the county and each incorporated city in the county.

Authorities warned at a news conference Wednesday that residents should avoid the developed flood channels when thunderstorms appear.

Keeping an eye on weather forecasts also is advisable, as Adair said thunderstorms can usually be predicted one to three days in advance.

Review-journal staff writer Blake Apgar contributed to this report.