National Weather Service Weather Forecast Office

A deep upper level low pressure system that became relatively stationary over the Great Basin beginning on September 10th provided a steady stream of near record monsoon moisture over New Mexico.  Multiple upper level disturbances pushed north and northeast across the region within the monsoon moisture plume through the 18th producing widespread historic rainfall amounts.   The focus for widespread, long duration heavy rainfall waivered across the state during the 9-day period, ensuring that everyone would get a healthy dose of much needed precipitation.  The focus for heavy rain from the 10th to the 12th was primarily over southern and eastern New Mexico.  After much of eastern New Mexico experienced a record to near record deluge of rainfall and flooding, the focus shifted into central and western New Mexico from the 13th to the 15th.  Widespread heavy rains became more convective from the 16th to the 18th, focusing torrential rainfall over much smaller areas of the state.  These convective rains on top of the saturated soil conditions left over from multiple days of widespread heavy rainfall exacerbated flooding concerns.  Record to near record river flooding and areal flooding was observed in several areas of northern and central New Mexico by the end of the period, while numerous locations reported disastrous impacts from flash flooding as well. 

Total rainfall amounts over the 9-day period averaged 3 to 6 inches and in some areas just over 10 inches.  Several river gauges reported record to near record crests and in a couple of cases gauges were completely destroyed.  Emergency management reported disastrous impacts to residential, commercial, and transportation infrastructure across northern and central New Mexico.  Significant coverage of this event was broadcast by local and national media outlets.  Social media coverage of the event was extraordinary as residents and visitors to the region shared valuable feedback with the National Weather Service.  A total of 11 counties, 4 cities and towns, and 4 pueblos, including the Navajo Nation, were included in a statewide disaster declaration.  The New  Mexico State Emergency Operations Center was in command at Level 2 operations for several days.