Abstract
This article reviews the current state of knowledge of sting jets (SJs) in extratropical cyclones. SJs were formally identified in 2004 by the pioneering work of Keith Browning. Reviewing this and subsequent studies, we define the SJ as a coherent air flow that descends from mid‐levels inside the cloud head into the frontal‐fracture region of a Shapiro–Keyser cyclone over a period of a few hours leading to a distinct region of near‐surface stronger winds. It therefore lies above the cold conveyor belt during some stage of its life, but, at least in some cases, descends to reach the top of boundary layer ahead of the cold conveyor belt. It is not attributed to a specific mechanism in this definition. We conclude that it is likely that a continuum of SJ descent and speed‐up mechanisms exists. At one extreme is balanced descent partly associated with frontolysis in the frontal‐fracture region. More horizontally small‐scale and stronger frontolytic descent may occur associated with weak stability to slantwise convective downdraughts. Instability to slantwise convective downdraughts may occur in some systems, leading to multiple slantwise convective downdraughts associated with the release of conditional symmetric instability and even, possibly, symmetric instability. The global climatology of SJs and the interaction between the atmospheric boundary layer and SJs are revealed as specific areas where more research is needed. Finally, we describe eight myths and misunderstandings that exist in the current literature with the aim of guiding future research into the SJ phenomenon.
Highlights
Extratropical cyclones (ETCs) are a major cause of hazardous weather, primarily in the form of wind and rain or snow fall (e.g. windstorm insured-loss estimations in the Extreme Windstorm Catalogue: http://www.europeanwindstorms.org, in which the largest insured loss of $8.2bn is for the 1990 windstorm Daria)
They “conclude that Conditional Symmetric Instability (CSI) release has a role in the generation of the sting jets (SJs), that the SJ may be driven by the release of instability to both ascending and descending parcels, and that DSCAPE could be used as a discriminating diagnostic for the SJ.”
5.7 Summary of mechanisms for sting jet formation Considering the discussion above, it seems likely that a continuum of behaviour occurs, from balanced descent partly associated with frontolysis in the frontal-fracture region, through horizontally smaller scale and stronger frontolytic descent associated with weak stability to slantwise convective downdraughts, to multiple slantwise convective downdraughts associated with the release of CSI and even, possibly, Symmetric instability (SI)
Summary
Extratropical cyclones (ETCs) are a major cause of hazardous weather, primarily in the form of wind and rain or snow fall (e.g. windstorm insured-loss estimations in the Extreme Windstorm Catalogue: http://www.europeanwindstorms.org, in which the largest insured loss of $8.2bn (indexed to 2012 values) is for the 1990 windstorm Daria). But ahead of the CCB, he identified a distinct mesoscale region of extremely strong surface winds and, especially, gusts close to the “tail” of the characteristic “hook” of the cloud head and distinct from both the WCB and the CCB. This region of gusts was responsible for most of the damage caused by the storm. The term SJ alludes to its relatively short-lived nature (especially at the ground) compared with, for example, the WCB and CCB This presents a forecasting challenge even today, as direct evidence (in terms of surface wind) of its presence may not be available until the last minute.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Quarterly Journal of the Royal Meteorological Society
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
