What Is Storm-Relative Helicity?
A measure of how much spin storms can pull in from the low-level winds. Higher values favor rotating storms and tornadoes. In technical terms: The integral over a layer (commonly 0-1 km or 0-3 km) of the dot product of storm-relative wind and horizontal vorticity, in m²/s²; 0-1 km values above about 100-150 m²/s² favor tornadic supercells.
Also called: SRH, Helicity
Storm-Relative Helicity In Plain English
A measure of how much spin storms can pull in from the low-level winds. Higher values favor rotating storms and tornadoes.
The Technical Definition
The integral over a layer (commonly 0-1 km or 0-3 km) of the dot product of storm-relative wind and horizontal vorticity, in m²/s²; 0-1 km values above about 100-150 m²/s² favor tornadic supercells.
Lessons That Use Storm-Relative Helicity
- Wind Shear And Hodographs Unit 6: Stability And Soundings
- How Tornadoes Form Unit 8: Tornadoes
