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| Countless logs and debris floats in a tributary of the Colorado River in the Grand Canyon after a severe flash flood. At least two people died, and 15 are missing. More flash floods are underway today. |
So far, two people have been confirmed dead in the flash flood.
The National Park Service said it recovered the body of a 46-year old man from the Crystal Rapids along the Colorado River. About 15 people are still unaccounted for. The flooding was concentrated along Bright Angel Creek, a tributary of the Colorado River.
As of early Sunday 62 people had been evacuated from Phantom Ranch and the lower North Kaibab Trail. Additional evacuations are expected.
In one area, park rangers ordered people to run as fast as they could across a foot bridge to safety. Moments later, the bridge collapsed.
Phantom Ranch is a lodge at the bottom of the Grand Canyon, on the east side of Bright Angel Creek, a little over a half mile north of the Creek's confluence with the Colorado River.
Footbridges along Bright Angel Creek were destroyed. The flash flood also destroyed part of the Transcanyon Waterline, which supplies water for the park's use.
Phantom Ranch, Bright Angel Campground, Phantom Ranch Canteen, North Kaibab Trail, the Black and Silver bridges and traffic to the Colorado River are closed until further notice.
Overnight accommodations at the park have been suspended for now, and water restrictions go into effect today.
Video showed muddy, debris-filled water rushing through the canyon. Pieces of buildings and/or RVs floated in the water.
WHY THE FLOOD HAPPENED
Flash floods often occur this time of year in and around the Grand Canyon, but this was far worse than the usual episodes of high water.
Near where the worst of the flooding occurred, 1.24 inches of rain fell, including 0.84 inches within an hour.
That might sound like much to those of us in the humid East, but the steep landscape of rocks and sand does not readily absorb water. Downpours tend to run off into flash floods.
The Southwest is in the middle of its annual monsoon season, when moisture from the Pacific Ocean and the Gulf of Mexico are drawn into the deserts by the circulation created by an atmospheric heat dome of high pressure near the region.
This year's monsoon is wetter for several reasons.Underlying it all is climate change. A warmer atmosphere can hold more water, especially under the right conditions. So monsoon rains have been in general getting heavier over the years.
In Arizona, monsoon rainfall is becoming more intense even as daily average rainfall in the state has decreased. In other words Arizona is having fewer rainy days, but when it does rain it more often comes in torrents leading to flash floods.
It's worse this year because a record breaking El Nino is heating up the eastern Pacific Ocean waters to record heights. A separate "marine heat wave" is making Pacific waters hot further north. The combination is adding a lot of humidity to the Desert Southwest air, creating more an overload of atmospheric moisture.
Moisture from the remnants of Tropical Storm Iselle were also drawn into the volatile atmospheric mix over Arizona.
Deluges have been the result.
MORE FLOODS?
It'll be just as bad today, if not worse in some areas.
Today, we have a risk of flash floods across all of Arizona, almost all of Utah, the western half of Colorado and western New Mexico.
The risk of dangerous flash floods is especially high in northern Arizona, including Grand Canyon National Park and in southern and central Utah.
By late morning local time, flash warnings were up in parts of Utah. The storms will intensify during this afternoon, so the flooding will surely become more widespread.
The flood risk will diminish tomorrow and the day after - for now.
Computer models suggest a dying tropical storm early next will send extreme amounts of moisture into southern California, Arizona and Nevada. Big time severe flood could result if this scenario proves accurate.
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