I had tried this in a size 40 on in a store and loved it.  Ordered from Amazon to save some money and found it large in the bust and tight in the rear.  I'm a usually a medium, size 8-10, kind of person but this was too roomy.  Tried it on in the store one size down and it was better.  This jacket is very well made - the kind you'd keep for many years.  It is lined with a soft warm fabric so it's not a shell.  Would be too warm for a summer shower and probably too light for under 20 degrees.  It's also slightly stiff although it moves well with the body.  Might be a bit bulky for stuffing in a bag or backpack which is a concern for travel.  The styling is gorgeous - tapered and a-line below the waist.  Probably made for a taller person and wouldn't work for a petite.  Covers the bum plus a little more length which is nice for warmth and dry in a the rain.  I'm definitely thinking of getting this in the smaller size.