Help please - lightweight maternity coat needed

[GillianLovesMarmite]

I'm 29 weeks pregnant and I almost got soaked this morning as it was raining and none of my coats do up now... I have some heavy winter coats (like my babywearing mam coat) but it's also really warm...
I tried Primark at lunchtime, but ended up looking like I was wearing a tent in everything I tried on and am now feeling a bit despairy as I don't want to spend a lot of money as I've not got all that long to go, but equally I don't want to get wet in the rain.
Please help with your suggestions. I would need a size 18 in maternity wear.

Here?

trench coat

Ooh! both good suggestions! I'm liking the red particularly though! Thanks mamas!

wow, that red one is gorgeous, and at £30.00 makes me (only slightly) wish I was pregnant!

get something double breasted.

my normal winter coat lasted all through pregnancy in the middle of winter. as bump grew i just did fewer buttons but because it was double breasted my giant tummy didn't stick out in the cold/rain/ snow.