Rain and floods and tornadoes, oh my!

Another burst of tropical moisture slams the Southwest, and this one’s a real doozy

A couple of bald eagles watch the storm move in from a cottonwood tree near Norwood, Colorado. Jonathan P. Thompson photo.

Yet another round of storms slammed the Southwest this week, wreaking havoc across the region and hitting the Four Corners Country hard. By Friday morning, the rain had let up in most places, but some rivers are continuing to rise toward flood levels. Here’s a quick rundown of some notable impacts, then on to the hydrographs:

• The Navajo Nation once again suffered major flash flooding that washed out roads or otherwise rendered them impassible. Perhaps the worst of it unfolded in Dennehetso, a low-lying community between Kayenta and Mexican Water, where the Navajo Department of Emergency Management and other agencies had to use a specialized vehicle to rescue 30 people from flooded homes.

• An emergency was declared in Hurricane, Utah, after a couple of inches of rain fell in the headwaters of Gould Wash, which then partially inundated the southwest Utah community.

• An evacuation order was issued for low lying areas along the San Juan River, as stream levels met and then exceeded last October’s high-water levels.

• The Colorado Department of Transportation closed a segment of Hwy 550 over Red Mountain Pass, CO 17 over Cumbres Pass, Hwy 160 over Wolf Creek Pass, CO 151 near Chimney Rock, and a section of Hwy 160 west of Pagosa Springs due to flooding, debris flows, and/or safety concerns. Those segments remained closed as of Friday morning at 8 a.m.

  

• And in Heber, Arizona, a possible tornado caused widespread damage.

Now for a look at some streamflows.

The Animas River in Durango reached 8,700 feet and rising as of 7:30 a.m. on Friday. That’s the highest it has been since the flood of 1970 (11,600 cfs) and the 11th highest since consistent measurements began in 1911 (though it’s likely to move into 10th place later today). Further downstream, the Cedar Hill gage near the New Mexico-Colorado line was reading 10,800 cfs on Friday morning, and will likely continue to rise, with the potential for downstream flooding (it will also add to the San Juan River’s considerable flows).

The San Juan River in Pagosa Springs hit “action stage” late Thursday. On Friday morning it reached 9,100 cfs and appeared to still be on the rise. That is the third highest recorded streamflow at that gage, following the flood of October 1911 (25,000 cfs) and the June 1927 flood (16,000 cfs).

Further downstream, the San Juan River near Bluff, Utah (actually, the gage is located closer to Mexican Hat, and is just below the confluences with Chinle and Comb washes) reached 16,200 cfs on Thursday afternoon. Navajo Dam sits between the high flows in Pagosa and this streamflow gage, so that will keep the upstream high water from increasing levels downstream even more.

The Little Colorado River, which gives a good indicator of conditions on the Navajo Nation, topped out at 17,100 cfs on Thursday evening. This gage has only been keeping peak streamflow records since 2003, but this level is by far the highest the river has been in 23 years (second place was 7,550 in 2012).

The Dolores River at Bedrock, Colorado, reached 4,560 cfs on Friday morning, which is the highest it has been since 2005, and the third highest since McPhee Dam started impounding water upstream in 1983.

While it’s been a bit too warm for this wet stuff to take the form of snow in the lowlands and midlands, it has left a good coating of wet, white stuff on the peaks. The Center for Snow and Avalanche Studies monitor at its Senator Beck Study Plot near Red Mountain Pass is recording 12.8 inches of snow, with about five inches of snow water equivalent. That’s significantly higher than what the nearby SNOTEL station is currently recording (2.8 inches of SWE).