Plans bring me to Edinburgh and possibly London mid December through the first week of January. Will the weather then permit some biking? Anything I should do or see? Me, wife, two daughters and a daughter's boyfriend. We all bike and like to explore. Thanks in advance.

Why not ask the folks in the UK Regional subforum. They live there.

Do you mean touring or riding your bikes around the city?

If you mean touring then I'd say it's not a good idea. Cold, wet, possibly snow, short days, pretty miserable.
Around town you could most likely ride unless there's snow/slush/ice. Why bother though - Edinburgh city centre is so compact that it's all walkable

+1. And London roads are so congested that for city sightseeing, it's pretty undesirable. There are Santander self-rentals all over, though, so if you want to cover some particular ground, you can do that.

Now, riding south of London in Kent presents some very nice opportunities on hilly roads and touring destinations to castles like Hever. Whether you want to undertake such trips in Dec/Jan requires serious consideration, though, as many tourist destinations are not open, and the weather poor.

Have you tried this search thing, like Google does ? https://www.google.com/search?q=Edin...hrome&ie=UTF-8

Common in many European cities and towns, You will Find a Tourist Information Centre, there.

I visited England in late December/ early January. The weather was remarkably mild in the southeast. I did cycle a little in London, though mostly on trails along the Thames. What I could tell you:

1. The temperature was decent, about 5-10°C midday.
2. It rained every other day, but not for more than an hour or two at a time.
3. The trails were muddy, so a cyclocross bike or MTB would be nice to have on them.
4. There is lots of traffic on the streets, so you need to be very careful. With driving on the left and various roundabouts, etc., it can be a little intimidating at first. Still, lots of people do commute by bike. Keep in mind that you can't ride on pavements.
5. You can't really bring the bike into pubs, etc. I wanted to have a beer in the pub's garden, but I was asked to take my bike outside the gate and leave it on the street. You'll need good locks in order to secure your bike for an extended period of time.

You might want to ask some locals for more details.

Daylight hours are shorter My tour on last week of February started inDublin Ireland and ended in the middle of november in Aberdeen

sun set was early on both ends . Inverness is at the same sort of Latitude as Juneau Alaska, which is about 58 degrees North

Weather is not predictable. I could be a wet 12C, a bone-chilling, damp 2C, or an icy -5.
I manage to ride through almost all of this, but fit studded tyres in ice.
You do get days of dry, not-too-cold, sunny conditions that make for great riding, esp in the morning.

For a short stay your best bet is to hire a bike locally if the conditions are OK.

It will start to get dark by 3:30pm and be dark by 4:00.

There are some canal towpath rides that are good, easy rides for winter and Sustrans have some good routes mapped out.