We will be taking a walking tour in Wales, in the Wye Valley, late September. Should we expect fairly cold and rainy weather, or not? Don't want to pack a lot of weather gear that won't be necessary, although we know nothing is ever really predictable!
I was there 2 years ago in early/mid September and we didn’t have any rain for the 10 days and it was mild, but the weather this year has been particularly unpredictable, so be prepared for a shower. You would be unlucky if you had wall to wall rain. By late September, the evenings may be cooler.
No one can tell you until the first week of October.
The reason why the British talk about the weather so much is because it is so unpredictable and changeable even in the space of one day.
That said, you should absolutely bring decent wet weather gear with you, especially if you are doing a walking tour.
It will almost certainly rain at some point during your trip. At that time of the year it is certainly possible to be very wet and almost certainly won't be that warm.
Bring the appropriate gear and be prepared to use it, even if that means taking it off and on during the course of a day.
We did Wales in Late September. While it was still warm we did have some downpours. I had a light weight trench coat and really appreciated it, as sometimes the wind blew the rain sideways. Bring a pull on knit hat. But most of the time we had excellent weather for touring. We did have a fog in the mountains but it added to the mystique. I found that fleece pullover will keep you dry without the weight. Don't wear jeans....they take too long to dry.
As others have mentioned in other threads, it's layers you need. I tend to go for thin-ish layers. For example, t-shirt, long sleeved half zip, fleece jacket and/or windproof top. You will need a decent rainproof jacket with you in case of a worst case scenario and I always carry a pair of waterproof over trousers with me. You may be able to pick up a cheap pair of these on arrival in the UK. In the event of wet weather I find gaiters useful especially if you are walking through long wet grass, but these are not essential. Finally, but probably most importantly, you'll need a decent pair of walking boots/shoes dependent on the terrain you are covering.
A story I always tell about the vagaries of the British weather is an ascent of Ben Nevis in Scotland. We set out in shorts and t-shirts on a sunny warm day in September. At the top I had on every last stitch of spare clothing I had brought with me including cagoule and over trousers and because I'd been silly enough to think I had no need to pack a warm hat and and gloves, I had to borrow my wife's spare pair of mittens. By the time we reached the valley floor again we were back in shorts and t-shirts, peeling layers off as we descended!
I'm assuming the Wye Valley won't be quite so extreme, but it never hurts to be prepared for the weather to take a sudden, if temporary, turn for the worst!
Have a great trip!
We were there in early October and it was nice. A little chilly in the evening, but just take a light jacket or sweater. Yes, it might rain, so be prepared.