Typical Appearance In Vertical Cross Sections

Here are some relevant features from the NWP parameters that describe the vertical structure of the SALLJ events:

  • Meridional wind: maximum of the northerly wind immediately to the east of the Andes at around 850 hPa.
  • Equivalent potential temperature: statically unstable area accompanying the wind maximum.
  • Meridional moisture transport: maximum of moisture transport from tropical latitudes accompanying the wind maximum.
  • Convergence and vertical motions: maximum of convergence at low levels and maximum of vertical motion at middle levels in the LLJ exit region.

Zonal vertical cross section

Meridional Wind and Theta-e

Lat: 27 °S. Meridional wind velocity (shaded, m/s); black: isentropes (theta-e, K) - 28 Dec 2002 12 UTC

Meridional Moisture Transport

Lat: 27 °S. Meridional moisture transport (shaded, g/kg*m/s); black: isentropes (theta-e, K) - 28 Dec 2002 12 UTC

Meridional vertical cross section

Low Level Convergence and Meridional Circulation

Lon: 60 °W. Zonal wind (shaded, m/s); contours: divergence; arrows: meridional circulation (m/s) 28 Dec 2002 12 UTC