Flash Flood in San Juan County, New Mexico

A strong thunderstorm near the Colorado and New Mexico border produced flash flooding along the La Plata River. No structures were damaged, but water did cover the roadway along New Mexico State Road 170 and nearby roadways such as Road 1788 south of La Plata. Water marks suggested that the flood waters covering the roadway were about 100 yards wide and 2 to 3 feet deep.

With an area of high pressure centered over northeast Colorado, above normal amounts of subtropical moisture continued to stream into New Mexico on July 27, 2021. Another very active monsoon day soon got underway across northern and central New Mexico as daytime temperatures warmed and the atmosphere destabilized. Thunderstorms initially developed over the high terrain areas with steering flow moving them in a very slow northerly direction. One particular thunderstorm southeast of Taos produced less than a half of one inch of rain on the Luna burn scar, but it was enough to produce flash flooding on the hydrophobic surface. Meanwhile, a strong thunderstorm along the border of Colorado and New Mexico caused flash flooding on the La Plata River which resulted in flash flooding in the town of La Plata. Unfortunately, an additional fatality occurred in an Albuquerque arroyo as a thunderstorm producing heavy rainfall quickly filled up the city's arroyos. Emergency personnel had to conduct two water rescues with the individuals being swept into the fast moving water in the arroyo. One water rescue was successful, but the second was not.