"John Hall" wrote in message
...
In article ,
Nick Gardner writes:
Aye Graham, when I've looked at the Met Office charts for this summer
and they've shown weather front after weather front passing over but
apart from a bit of cloud build up, you would not have known they were
there.

Aarrghh! You've been infected with the dreaded "weather front" virus by
the BBC, who don't seem to realise that in the context of a weather
forecast that is the only sort of front they can be.
--

To inject a bit of science. Most summer fronts are of the split variety.
This has been the case this year with one or two notable exceptions. A split
cold front is where an upper front runs ahead producing precip. aloft which
can evaporate before reaching the ground. The surface front is very weak
being just a band of cloud and patchy rain but marking the surface
transition to cooler air. In between is a shallow moist zone of cloudy
drizzly conditions. Occasionally a jet streak will overrun the shallow moist
zone and, with added vorticity, increasing instability leading to heavy rain
and sometimes thunder. This has happened a few times this summer. It looks
like magic when models do that as rain seems to come from nowhere in an
otherwise weak frontal system, but it is all well understood 20th Century
science. The term "weather front" is a massive simplification. There are
many many types of front.

Will
--