The National Weather Service’s Aviation Weather Center (AWC) has issued a Severe Turbulence Alert for portions of the northeast which includes the airspace above and around Pennsylvania’s Philadelphia International Airport (PHL), New Jersey’s Newark Liberty International Airport (EWR), New York City’s LaGuardia (LGA) and DC-area airports of Dulles International Airport (IAD), Ronald Reagan National Airport (DCA), and Baltimore-Washington International Airport (BWI.) Many other airports throughout the region and aircraft flying in the airspace above are impacted by this alert. Major U.S. carriers American Airlines, Delta Airlines, and United Airlines all have a significant presence in this region.
Specifically, SIGMET YANKEE 2 has been issued through at least 0558 UTC tomorrow, extending an alert that was previously in effect over a smaller portion of this region earlier today. The AWC says that there is occasional severe turbulence between 13,000 and 31,000 feet due to wind sheer associated with the jet stream.
Wind shear is a difference in wind speed and/or direction over a very short distance in the atmosphere. Airline pilots generally regard significant wind shear to be a horizontal change in airspeed of 30 knots (15 m/s or 34 mph) for light aircraft and 45 knots (23 m/s or 51 mph) for traditional airliners flying at flight altitude.
Flying through turbulence can be dangerous, with injuries encountered on U.S. airline flights over the last several months.
In February 2023, a Newark-Tampa flight operated by United Airlines encountered severe turbulence. When flight 600 finally landed in Tampa, it was met by paramedics that treated passengers and crew at the scene. Ultimately, 1 flight attendant and 2 passengers needed hospitalization after being examined at the airport for injuries sustained during the rough flight.
Last winter, a United Airlines 767 jet encountered severe turbulence on its flight to Houston, Texas. Due to that encounter with rough air, 3 crew members and 2 passengers had to be rushed to the hospital for care upon landing.
The day before the Houston incident, Hawaiian Airlines Flight 35 flew through severe turbulence before landing at Honolulu International Airport after originating in Phoenix, Arizona. A Mass Casualty Emergency Event was declared, with dozens of passengers needing care for injuries sustained in the violent ride. Officials with Honolulu Emergency Medical Services and American Medical Response say the flight encountered the extreme turbulence about 30 minutes prior to landing; they treated 36 patients at the airport. 20 patients, ranging from a 14-month old toddler to older adults, were transported to hospitals near the airport, some with serious injuries.
Known as a SIGMET, short for Significant Meteorological Information, the severe weather advisory issued by the AWC contains weather-related information concerning the safety of all aircraft passing through a specific zone. Sometimes AIRMETs are issued too; an AIRMET consists of turbulence, visibility, and icing-related warnings that are less severe than those in a SIGMET.
