Key Parameters

  • Height contours at 500 hPa:
    • Distribution of height at 500 hPa indicates boundary between closed synoptic systems:
    • To the rear of a trough
    • To the rear and in front of an ULL, in the tear - off stage of development
    • At the deformation zone between two troughs and two ridges
  • Equivalent thickness:
    • A distinct gradient of equivalent thickness accompanies the cloud band
    • Mostly weaker than "classical" fronts
    • The appearance of this parameter is similar within all 3 types of Baroclinic Boundary
  • Thermal front parameter (TFP):
    • Maximum of TFP associated with the cloud band
    • Normally, weaker than "classical" fronts
    • No significant propagation
    • The appearance of this parameter is similar within all 3 types of Baroclinic Boundary

 

Height contours at 500 hPa

  1. At the rear of synoptic scale trough

    2. 19 October 2002/06.00 UTC - Meteosat IR image; cyan: height contours 500 hPa
  2. Baroclinic boundary associated with ULL

    3. 05 February 2002/06.00 UTC - Meteosat IR image; cyan: height contours 500 hPa
  3. Baroclinic Boundary associated with deformation zone at a saddle point of upper height Fields

    4. 04 April 2002/06.00 UTC - Meteosat IR image; cyan: height contours 500 hPa

 

Thermal front parameter (TFP) and equivalent thickness

29 November 2002/12.00 UTC - Meteosat IR image; blue: thermal front parameter (TFP) 500/850 hPa, green: equivalent thickness 500/850 hPa