John Smith wrote:
Hi all

Is there an FAQ for this group, or do you know one for weather elsewhere?

I'd like to find out what the relevance of thickness (other than
temperature) is on synoptic charts. Someone told me something once, but I
can't remember what was said. Something about wind direction, fronts and
thickness.

Thanks
JS

Lows tend to move parallel to thickness lines, which they then of
course distort, causing the Low most often to turn to the left. The
speed of the Low depends on the thickness gradient or thermal wind.
This is the vector difference between the geostrophic winds at 500 mb
and 1000 mb.
A surface cold front is often found at the warm edge of an area
of enhanced thickness gradient. Hope that helps a bit.

Tudor Hughes, Warlingham, Surrey