The remnants of Kay to deliver flooding rains to the Desert Southwest

By Jennifer Gray, CNN meteorologist

Five days after Hurricane Kay made landfall along the Mexican coast, the storm’s remnants are still causing problems hundreds of miles away.

Those remnants will pump an incredible amount of moisture into parts of the Southwest on Tuesday, triggering the potential for dangerous flash flooding.

“This is a somewhat unusual setup for Utah, as it is a bit uncommon to get tropical remnants moving through, so am anticipating a heightened risk for flooding,” the National Weather Service office in Salt Lake City said.

Dangerous flash flooding possible Tuesday

There’s a moderate risk of flash flooding (level 3 of 4) for portions of Nevada, Arizona and Utah and a more widespread lesser flooding risk for much of the Desert Southwest and Intermountain West.

According to the flash flood watch issued by the weather service, “abundant moisture sourced from the remnants of Kay will lead to periods of heavy rain in the watch area. Rainfall rates of 1 to 2 inches per hour possible.”

This is significant for the desert region because the area isn’t accustomed to heavy rainfall and so it doesn’t take much to trigger flash flooding.

Areas that see sunshine Tuesday and daytime heating also will be areas to watch for this flooding, as the heat from the afternoon sun will provide a moist environment for storms to thrive — because a warmer atmosphere can hold more water.

“We’re super juiced,” said Barry Pierce, weather service meteorologist in Las Vegas, meaning that the air has ample moisture to produce storms. So, any storms that form are producing heavy rain.

While the majority of the region will see anywhere from half an inch of rain to an inch or two, any areas that are under any slow-moving storms producing torrential downpours could be in trouble.

“We’re seeing 2-inch rainfall rates to rapidly bring on flooding and water could rise quite quickly, so people just need to be aware of their surroundings,” Pierce said.

Danger in the National Parks

Pierce told CNN that places like slot canyons and Zion National Park are areas he’s concerned about as they are targeted for extreme rainfall throughout the day.

“So people hiking and recreating definitely need to stay aware today,” Pierce said.

The weather service in Salt Lake City tweeted a graphic showing the risk level in all the National Parks across Utah.

This comes on the heels of flooding in Death Valley National Park and the deadly flooding in Las Vegas a month ago as the Desert Southwest experiences its wettest monsoon season in a decade.

Watch a woman being rescued from Arizona floodwaters last month

More potential flooding on Wednesday

The potential for flooding will extend into Wednesday as well, with the greatest threat shifting slightly to the north.

Much of Utah, Nevada and parts of Colorado will be under a level 2 of 5 risk for excessive rainfall. Ample moisture will still be in place, providing another day for flooding.

“This should be enough to support 1″ an hour rainfall amounts within any heavier convective cells,” said the Weather Prediction Center.

By Thursday, drier air will move into the region as the remnants of Kay finally make its exit, leaving behind much more pleasant conditions.

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CNN meteorologists Judson Jones and Chad Myers contributed to this article