"Tudor Hughes" wrote:
Phil Layton wrote:

http://217.160.75.104/wz/pics/brack4.gif
Interesting feature on the EGRR T+120

It's gone on the T+108, or at least its amplitude is
insufficient for it to have a 4-mb isobar round it. I wonder if these
things ever happen in reality.

Heat lows form quite regularly over the UK in a flat
anticyclone or ridge ... the amplitude is rarely more than
2mbar so the pressure would have to be just right to
get a closed isobar over England - or Scotland. So if it
appears on the 12z it is quite reasonable, on the 18z
slightly less so, whereas on the 00z or 06z charts it would
of course be an error.

My only concern on this occasion is that the anticyclone
might not be flat enough.

Philip Eden