North Flow Returns to MSP
Residents across the metro may notice a change today as for the first time in weeks, conditions have allowed Air Traffic Controllers (ATC) for the Minneapolis-St. Paul International Airport (MSP) to operate flight traffic in a North Flow pattern. On Friday, June 9th, aircraft may now be seen arriving and departing to the northwest on MSP's parallel runways, 30L and 30R. The airport has operated in a primarily South Flow pattern since May 20th, with aircraft arrivals and departures heading to the southeast on parallel Runways 12L and 12R as well as departures on Runway 17. In rare fashion, there were more departures from Runway 22, the seldom-used crosswind runway, than there were from Runways 30L and 30R between May 21st and June 8th.
The primary determinant for air traffic patterns at any airport is wind. Although ATC has to consider a multitude of factors, there is always an attempt to assign aircraft to runways that provide the greatest amount of headwind for takeoffs and landings, especially when wind speeds exceed 10 miles per hour.
Safely directing air traffic is an immensely rigorous and complex duty. Hundreds of aircraft fly in and out of MSP each day. Therefore, changing the flow of air traffic once it has been established is no easy feat. Air traffic controllers have to consider the predominant pattern of winds over an extended period of time and cannot change runway assignments very quickly. Winds at altitude are considered in addition to winds at ground level, particularly to allow for safe arrival landings.
Due to its geography and continental wind patterns, MSP typically experiences predominant winds out of the south and east from the middle of May through the summer. However, MSP experienced higher levels of wind from the south and east during May 2023 than in recent years past. As a result, the airport spent 75% of the month in South Flow, as opposed to 52% of May 2022 and 59% of May 2021.
The weeks long stretch in a South Flow configuration left residents residing under these flight patterns without the respite that is provided from typically varied configurations. Weather conditions over the next week should result in days spent in configurations that vary. More information about runway use is available here. The MAC FlightTracker Tool can also be used to review existing and historic flight activity. For questions regarding airport activity and information about runway use, contact the Metropolitan Airports Commission's Community Relations Office at 612-726-9411 or online.