Storm Slinky

The storm slinky represents a 2D view from above of the lifted parcel trajectory after a 5 m/s nudge at the Level of Free Convection (LFC). After the parcel is nudged, the derived buoyancy accelerates the parcel to the Equilibrium Level (EL). The spacing of the rings is proportional to the horizontal displacement during a fixed time, and the color coding matches the hodograph. Kidney bean shapes are common with classic supercell wind profiles, while other unusual slinky shapes may suggest unfavorable aspects of the wind profile. Some aspects of the display include:

time - time of integration from the LFC to the EL, annotated in the upper left of the slinky display (e.g. 357 s)

white line - storm motion direction

circle color - parcel circles are color coded relative to height coincident with the colors on the hodograph

deg - updraft tilt off of vertical calculated using the angle between the first ring and last ring (e.g. -104 deg). According to SPC, there appears to be an error in the calculations at this time.