Present surface frontal analyses suffer from the defect that frontal positi
ons are typically not collocated with zones of intense temperature contrast
. Further, individuals typically do not agree as to the existence, type, an
d location of fronts.
The author argues that the lack of a surface temperature analysis is mainly
responsible for these flaws, and it is proposed that such analysis, prefer
ably of potential temperature in regions of variable terrain elevation, bec
ome part of routine procedure. Such an analysis will reveal nonfrontal baro
clinic zones of considerable intensity. Most cold fronts, except the strong
est ones, are denoted as baroclinic troughs, propagating eastward in the pr
evailing westerly flow. It is argued that when a meridional cold front exis
ts in the presence of even a small meridional temperature gradient, the win
d shift should propagate away from the intense surface temperature gradient
, which then weakens. An explanation is provided, based on quasigeostrophic
theory. It follows that fronts are short-lived phenomena.