close all entrances to Yellowstone National Park through Wednesday at the earliest.NPS officials said there has been substantial flooding, rockslides and mudslides across numerous roadways after areas picked up at least 3 inches of rain, with some areas seeing a half-foot or more.HOW TO WATCH FOX WEATHER ON TVThat amount of rainfall combined with rapid snowmelt has allowed for the Yellowstone River to rise above levels that haven't been seen in more than 100 years.Flooding and rockslides have closed entrances to Yellowstone National Park. (Yellowstone National Park)The National Weather Service in Billings, Montana, said the Yellowstone River at Corwin Springs is at 13.85 feet, well above the previous record crest of 11.5 feet.WHAT DOES THE TERM '100-YEAR FLOOD' ACTUALLY MEAN?People along the river in the Paradise Valley, especially those camping along the river, are being advised to seek higher ground immediately.Severe flooding in the Yellowstone area on Monday, June 13, left many roads inaccessible in Red Lodge, Montana. (Credit: @Norseman on YT via Storyful)The NPS said there would be no inbound visitor traffic allowed into the park until the situation stabilizes and officials can begin to assess damage to roads, bridges and other facilities within Yellowstone National Park.All entrances to Yellowstone National Park are closed.