what to pack for London mid/end Sept?

Hi all, Just thought I'd drop this thought out there....I'm headed to London, arriving Sept. 20 for 2 1/2 days, then a week in Bath. I'm guessing that I will be bringing mostly all black (and other colors to mix in), but what will the weather be like?

Would I go wrong with a sweater or two, just 'in case'?

TIA!

A couple of years ago, I was there for the last week of September, and I wore what I'd describe as 'Fall weather' clothing - I only needed a light jacket in the evenings, and during the day was fine with sweaters/sweatshirts. It also rained every day, so bring an umbrella (although I'm sure you know that).

Of course, I don't know if this was typical September weather! But it was IMO a wonderful time to visit.

The temperatures in London and Bath are similar. For September, the normal high is 65 degrees F. and the normal low is 51 degrees F. The weather will be definitely autumnal, not Indian summery.

Interiors can be cool or can feel close; indoor climate control is less common. The sort of things I like to bring are jackets or cardigans that are warm enough for outdoors (usually less windy than in N. America) but still look nice indoors. In pubs, in particular, people stand around in their outerwear.

Outside of London I would caution against doing the all black thing. Among the older generation in particular black is still for funerals, or those into the Goth scene. Brits aren't as enamored of black as those of us in North East American cities, probably because black is not very flattering to the typical English rose complexion.

You wouldn't go wrong with a wool coat, 'just in case'. It can get pretty chilly even during the daytime, even in summer, as other responders have said.

A hot spell isn't impossible, either. You should probably not finalize your packing list until just before leaving for the airport