wrote in message
oups.com...
Noticed that the chart for yesterday midday showed a cold front over
the southern UK, yet maximum temperatures yesterday were about 5C
warmer than the last few days? Why was this classed a cold front when
it introduced warmer air? Temperatures were both warmer by day and much
warmer by night, so both surface and upper air appeared to be warmer.

Nick

A front marks a strong wet-bulb potential temperature gradient, so very
roughly speaking what you say about surface and upper air tending to be
warmer holds.

However, think of the insolation factor over the last two days. Within the
cloud-ladened frontal boundary insolation was very slight, however here in
Manchester behind the cold front there was hardly a cloud in the sky to
inhibit the sun warming us up.

You don't give a location for the "5degC warmer than the last few days",
which is a bit general.

Joe
--
Withington, Manchester