Moisture from Tropical Storm Paine will induce flooding thunderstorms across the southwestern United States from Monday night into Tuesday night.
"[Paine] can lead to some enhanced rainfall across parts of the southwestern U.S. early this week," according to AccuWeather Meteorologist Evan Duffey.
Tropical Storm Paine is currently spinning a few hundred miles southwest of Baja California. As it tracks northwestward over the next couple of days, the storm is expected to strengthen into a strong tropical storm or hurricane.
Paine will slowly parallel Baja California and eventually stall offshore by midweek.
"The cool water west of the northern Baja California Peninsula will prevent Paine from directly reaching the southwestern United States," AccuWeather Senior Meteorologist Kristina Pydynowski said.
However, moisture from the storm will be drawn northeastward into the southwestern U.S. early this week. This will induce drenching showers and thunderstorms from western Arizona to southwestern Colorado late on Monday through Tuesday.
Heavy storms that can lead to flash flooding are possible in and around Flagstaff, Arizona, and Durango, Colorado.
A few showers and storms may even reach Los Angeles, San Diego, Phoenix and Las Vegas. The bulk of the heaviest rain, however, is expected to focus farther to the north and east.
Storms that do wander close to major airport hubs could cause delays for incoming and outgoing airline passengers for a time.
While the rain will fall over areas that are experiencing drought conditions, too much rain in a short amount of time can lead to flash flooding.
Rainfall amounts of an inch or more can fall in an hour or less, which can cause dry stream beds to become rushing rivers in a matter of minutes.
Motorists should be on alert for flooded and washed out roadways and reduced visibilities.
While storms in the Southwest are expected to become much less frequent on Wednesday, a new storm with heavy rain and October-like air will be taking shape across the Rockies.
Story content contributed by AccuWeather Meteorologist Jordan Root.