NOAA’s National Severe Storms Laboratory (NSSL) has a ten-year cooperative research venture with the Salt River Project (SRP), an Arizona power and water utility, to develop weather decision support tools for the company’s power dispatch, transmission operations, and water diversion. In 2011, an NSSL-produced prototype algorithm that provided advance notice to prepare for the impact of a severe dust storm in Phoenix. This week, NSSL launches a month-long study using mobile radar to verify its microburst and haboob prediction algorithms. These data help SRP serve 920,000 electric customers in the Phoenix area and deliver nearly 1 million acre-feet of water annually to a service area in central Arizona.
An NSSL algorithm developed in collaboration with Arizona’s Salt River Project (SRP) alerts the power company of the potential for a dust storm called a haboob. A haboob is a wall of dust that is pushed out along the ground from a thunderstorm downdraft at high speeds.
The Haboob Algorithm runs on NSSL’s Multi-Radar Multi-Sensor system at SRP, and automatically monitors the radar for thunderstorms reaching thresholds that could result in outflows producing strong surface winds and blowing dust. When thresholds are reached, SRP operational personnel receive an alert to prepare for the impact of wind loading on SRP power poles and substations.
The SRP was alerted two hours in advance of the haboob that struck Phoenix, Ariz. on July 5. This storm travelled at least 150 miles with wind gusts more than 60 mph and a leading edge almost 100 miles long. An estimated 10,000 people lost power.
On Monday, July 18 the Haboob Algorithm gave the power company 45 minutes advance notice to prepare for the impact of the storm in Phoenix.
The Salt River Project has a reputation for innovative use of radar and weather information in their daily operations towards highly efficient electrical energy production and transmission.
SRP is two entities: the Salt River Project Agricultural Improvement and Power District, a political subdivision of the state of Arizona; and the Salt River Valley Water Users’ Association, a private corporation.
The District provides electricity to about 920,000 retail customers in the greater Phoenix metropolitan area and the Association delivers nearly 1 million acre-feet of water annually to a service area in central Arizona.
NSSL’s dual-polarized mobile Doppler radar team coordinated operations with the Phoenix National Weather Service (NWS) Forecast Office and the NWS Radar Operations Center during dust storm events during July and August. Their mission was to collect data on the vertical extent of the dust to compare with the Phoenix NWS radar data, recently upgraded with dual-polarization technology.
To date, data has been collected on seven dust storms, with four of them being considered as “major.”
NWS forecasters observed a mysterious shadow in the radar data during the dust storm on July 19, 2011. They also re-examined dual-polarized radar data from the large dust storm on July 5, 2011. During that event, the shadows were more pronounced, and along and slightly behind the leading edge of the dust storm.
NWS forecasters hope combining both data sets will reveal some clues about their existence.