OGDEN -- An "atmospheric river" has been flowing over Top of Utah since Saturday morning, which explains the constant heavy rain.
More than 6 inches of water fell on Ben Lomond Peak and Ben Lomond trail measuring stations over the weekend. More than 3 inches fell in Liberty.
Some of the precipitation was rain -- most of it at the higher elevations was snow -- but it was all very wet.
Avalanche danger is widespread, ranging from high in most of the mountains east of the Wasatch Front to extreme near Provo.
Areas around St. George and Cedar City are being watched for flooding, and a road in Zion National Park washed out.
"A big trough in the eastern Pacific tapped into some tropical moisture, and we ended up with what we call an atmospheric river," said Larry Dunn, meteorologist in charge at the National Weather Service in Salt Lake City.
"And that hose, that river, is pointed at southwestern Utah."
This is the same weather system that was predicted to dump as much as 10 inches of rain on Los Angeles, he said, and is causing widespread fear of flooding and mudslides there.
Dunn said it will continue to soak southwestern Utah through Wednesday, but the northern part of the state will see less.
As of 11 a.m. Monday, Perry had 1.18 inches of new water, Bountiful had 1.7 inches, the northeast Ogden bench had 1.03 inches, South Ogden's bench had 0.99 inch, and Centerville had 1.12 inches.
Dunn said mountain areas got smacked with huge amounts of water that fell as either snow or rain.
Snowbasin resort, at mid-bowl, had 24 inches of snow, equal to 4 inches of water. Farmington Peak at 8,000 feet had 5.5 inches of new water, Monte Cristo had 4 inches, and Tony Grove had 3.8 inches.
Ski resorts near Salt Lake City were getting even more. Solitude had 42 inches of snow, which equals 4.7 inches of water. Alta had 29 inches of new snow, equal to 5.13 inches of water.
The heavy rains shut down a highway in Zion National Park.
Superintendent Jock Whitworth said a section of the Zion-Mt. Carmel Highway between the east entrance and the scenic loop is closed because of a washout, and the closure could last several days.
The damaged section is about two miles west of the park's east entrance, near Crazy Quilt Mesa. He said almost 2.5 inches of rain overnight eroded a 300-foot-long area adjacent to, and under, the road.
People traveling through Zion from its east entrance are advised to seek other routes.
Other towns near the park, including Hurricane and Virgin, were on alert as the Virgin River reached flood stage and exceeded its banks.
Washington County emergency services director Pete Kuhlmann said that, although some homes in the towns are in danger, no damage has been reported.
The river channel was widened after flooding in 2005, and that has helped keep flood waters away from structures, Kuhlmann said.
A flood warning was in place for Kane and western Washington counties through 3 p.m. Monday. Heavy rain, however, was expected to continue through Wednesday, Dunn said.
As much as 8 inches of rain has fallen in some areas of Southern Utah over the past few days, filling dry creek beds and making small streams dangerous to cross.
Because of the danger of flash flooding and washouts, travel along unimproved roads was discouraged.
The National Weather Service said Top of Utah should see a lessening of the storm, but still rates the chances of rain or snow at 60 and 70 percent through Wednesday.
High temperatures will be 41 and 42 most days, and lows will only be 33 and 34 through Wednesday night.
The long-range forecast put Christmas Day as sunny with a high of 39.
After all the rain and warm temperatures, that means it probably won't be a white Christmas.