England in January

It depends!
What do you call too rainy? As someone once said, there is no such thing as bad weather, only inappropriate clothing.
January can be wet, but like anywhere, it is becoming increasingly difficult to predict weather.
The thing about London is that there are so many attractions which are indoors, and the transport system is both good and dry.
I'd go for it.

It’s not really the rain or the cold that is the problem but the lack of daylight. It gets dark at 4pm. This is maybe ok if you’re in London but not if you want to explore the countryside.

London gets about the same amount of rain on a monthly basis all year round. But it does tend to feel wetter in the winter because, as noted, it’s colder and darker.

England is a big place - bigger than it looks, and with very diverse weather. The weather varies considerably around the country. Where are you talking about? Cornwall? Carlisle? Newcastle? Norwich?

Or by England do you mean London and the Home Counties?

Thank you so much for all the responses this far. My plan was to use London as a Base City, explore as much of London as I can see and then do like day trips to the Cotswolds, bath, and maybe do four or five days in Liverpool as despite being before my time I am a huge Beatles fan

All those places will be fine to visit in the winter except the Cotswolds (which are a bit overrated anyway compared to other scenic areas of the UK.). Rick’s general advice for Europe that in winter big cities are better than rural areas and small towns holds as true for the UK as anywhere else. I like Liverpool a lot (and I was there in winter). Five days is much more than enough for the Beatles sites but not too long if you do some day trips such as Chester and Manchester. What I did was split five days between Liverpool and Manchester and that worked very well. I did other things than Beatles sites when in Liverpool. There are some good museums there although one of the best, the maritime museum, is currently closed for renovation.

welcome to the Forums, darrenr1

I grew up in the Cotswolds so I know of what I speak.

The Cotswolds in January is drab, cold, wet, shut up, Dry January (not the weather, but for not drinking in January after the excesses of the Christmas / New Year season), and very dark.

The villages won't show to their best - the beautiful Cotswold Stone houses will be drab because of no or very little light. There will be glare when there is any light because the roads never dry, and the stone holds on to the moisture, the sun if it should appear at all will be very low from the south also contributing to the glare. Any thatched roofs will also be drab in that light.

Expect cars to have their headlights on all day - more glare - and the sun will be setting (what sun??) at or before 4pm, it will be under the cloud even if not raining quite dark by 3pm. Street lights will likely come on around 2pm.

As the Cotswolds are higher than the surrounding areas moisture often falls as snow or sleet.

What do you hope to see in the Cotswolds? What's attracting you?

And, very importantly, how will you get around? Car? Taxi? Big bus from London? Walking?

or it might be bright brilliant sunshine for the whole time. (pigs might fly)

Our rain is spread throughout the year. I wouldn't say that you have a greater chance of wet weather in January than you would do in July. Our weather is very difficult to predict. This week it's been 35C and sunny, the same week next year could be. 15C and raining.
London and the whole UK is geared up for when the weather is bad. There is lots to do indoors. You might even grt a cold, crisp spell. Hours of daylight are short in January, sunset at 4pm at the start, 5pm by the end.
Avoid the countryside and the Cotswolds. The scenery will be drab. Bare trees and muddy. Stick to the cities.
Outside London, Liverpool (Beatles), Chester, Newcastle, York even Manchester are worth googling. All easily reached by train.

WHY January. frankly, I don't like cold and wet myself.

The OP stated his reason for travelling in January. There's no reason not to. But sticking to the urban areas is a wise decision, given their many options for indoor activities. There are all kinds of choices besides just London and Liverpool.

A number of great country houses and other tourist attractions, mainly those outside the big towns, are closed during January for maintenance etc. It’s worth checking that the places the OP wants to go to are open. This doesn’t apply to major museums etc.

As someone who also lives in a rainy climate with short winter days (though not as short as those in the UK), I recommend also getting to the seaside when possible. More sky = more light. The seaside is easily reached from Liverpool and other cities, including Newcastle, which another commenter mentioned. See also: Edinburgh, which is not in England, of course, but it's on the same island, so...
Also, most of the time, the rain is falling so slowly that it really doesn't stop you doing anything. Shoes with a good, grippy sole, a waterproof rain jacket that fits over your various layers. A good tip I saw on the forum is to wear a ball cap (preferably waterproof and insulated if you can find one) to prop up the hood of your rain jacket.

We love a good rain walk but we also don't mind too much if we have to spend an afternoon in a pub with a fireplace, sipping, eating, reading our books.

It can be hard to find good places to travel in January in the northern hemisphere unless you're looking for winter sports-type activities. If you don't mind the very short hours of daylight that others have mentioned, there certainly is plenty to do here indoors, and if it's not raining you can even get some nature in- we once did a very nice walk along the Ridgeway on a frosty January day. That said I wouldn't base my trip around a lot of outdoor activities as the weather is rather unpredictable. Really the best things you can do in January are museums and pubs. As has been mentioned, certain types of attractions- such as historic homes- do close in the winter so have a look online for what you might want to see to check it will be open. Good luck with your planning.

as said, predicting weather is becoming increasingly difficult - but the coordination between earth and sun can be worked out. Also as said, the big problem with January is not rain but daylight. On 4th January sunrise to sunset in London is a gap of 8hours 19 minutes, in Liverpool it will be 8 hours and 1 minute. How much light actually gets through will be down to cloud cover.

Rural tourist locations are often closed until around easter, especially Monday-Friday.

Why you want to go the Bath is up to you, but you could have a look at Exeter. It has better chance of passable weather, in fact if you get a nice sunny day it isn't far to a walk on a beach, which you will probably have to yourself.

I can deal with limited daylight hours. And I can deal with cold weather so long as it is not too cold. For instance, Amsterdam in December in the low 20s was too cold for me.

But worst is rain in the winter. I visited York and Edinburgh in December a few years ago. The weather materially impacted my trip. Aside from some time in London, I have no interest in returning to the UK in the winter.

I also have a late January birthday and decided to spend it in London a few years back. I was there for five days and it was sunny the whole time. I realize that’s not the norm but museums, pubs and theaters are still great and much shorter lines. I was living in Maine at the time where January is when daylight starts to last until after 4:00 or 4:30 so the length of days wasn’t a problem for me. Enjoy your trip.

I'm not sure where you could go in the Northern Hemisphere in January for guaranteed dry weather. Even the Med and middle Eastern countries will be windy/cold, dark and possibly wet. The point we are trying to make is that London and the UK in general is geared up to provide things to do, even if the weather is poor. In fact, I can't think of a better city than London.

As well as short daylight hours and attractions being closed, countryside pubs and restaurants move to short hours in winter, often closed completely on Monday and Tuesday nights, not serving food every night or at lunchtimes etc.

Apologies but it’s London. It’s your birthday. Who cares if it rains? Plenty of things to see, places to eat, shopping available and countless free museums. Just make sure you pack a waterproof rain coat with a hood.

IMHO London is a city you visit anytime of the year. Make a list of what you places want to see and check their opening and closing times.

As noted sun will begin setting by 3:30-4pm. Plan you days accordingly.