The risk of localized flash flooding continues through the end of the week over part of the interior West.
Cities at risk for flash flooding during the random storms include Las Vegas, Phoenix, Tucson, Flagstaff, Albuquerque, Salt Lake City, Cedar City in Utah and Riverside, Calif.
According to Western Weather Expert Ken Clark, "An upper-level disturbance drifting in from the Pacific will focus an already in place flow of tropical moisture, known locally as the monsoon."
The end result will be more numerous and locally, extra-drenching showers and thunderstorms from interior California to New Mexico, northward to Utah and Colorado.
The storms will tend to favor, but not be limited to the high ground.
Isolated downpours can quickly flow downhill, causing canyons and arroyos to quickly fill with water.
The spotty downpours can also lead to debris flows in recent burn areas.
While area residents will welcome any non-destructive rainfall, a number of the storms will bring little or no rainfall, frequent lightning strikes and the risk for new wildfires.
"By the end of the week the storms will consolidate farther to the east and south over the Four Corners states as drier air invades from the north and west and the disturbance pushes inland," Clark added.
At such time the risk for flash flooding in Las Vegas and Phoenix will have ended.
Meanwhile, a stalled front will continue to bring rounds of drenching thunderstorms and the risk of flash and urban flooding to parts of the southeastern U.S. this week.
Easter Sunday will be a dry day across the Seattle area, but more showers and rain are ahead for the city.
After rain to start the Easter weekend, it will be sunny and warm on Sunday -- a nice end to the weekend.
Morning Easter activities should be fine, but a chance of showers and thunderstorms could impact any afternoon activities around Dallas.
There hasn't been any measurable precipitation in San Francisco since April 4.
Rain and thunderstorms spreading to the East on Tuesday will put the brakes on the warmup following Easter weekend.
Although spring may be in full swing, more than one-third of the Great Lakes remains covered in ice.
Sacramento, CA (1880)
7.24" of rain, heaviest in 24 hours.
Southeastern Ohio (1901)
Unusually heavy snow: Warren, OH, 35.5" of snow; Green Hill, OH, 28" fell in 36 hours.
Mississippi & Alabama (1920)
Tornado swarm killed 219.