Summer temperature in London and hotels with kitchens

There are plenty of extended stay hotels in London. They are sometimes known as Aparthotels. They offer kitchens in the rooms and laundry rooms in the building. Most of the kitchens have a stove top and microwave but no regular over. Tableware, pots and pans and cutlery are provided. Some better than others.

The biggest chains are Hyatt House, Staybridge Suites, Residence Inn, Citadines, Locke Hotels, Wilde by Staycity and Fraser Suites. There are also individual ones as well and I'm sure others will chime in with recommendations.

If you truly need a major kitchen, look into "Serviced Apartments." These are apartment buildings run like a hotel.

London temperatures in the summer can vary from pleasant to downright roasting. Usually August and September aren't as bad as July can be. While others might disagree, I suggest making sure your hotel has a/c.

I recommend taking a look at the actual, historical, day-by-day weather statistics for London available on the website timeanddate.com:

London weather--August 2023

It's really important to look at more than one year, because weather is highly variable. You can use the pull-down menu at the right, just above the graph, to change the month and year displayed.

August 2022 had an extended hot spell. The odds are good that you wouldn't encounter anything like that, but you could.

If you google "london weather monthly averages" google will put up at the top of the page the London weather averages by month for high temp, low temp and rain.

The average highs for the months you mentioned are June (70F), July (74F), August (73F) and September (67F)

I like Locke with their kitchenettes, and have a particular fondness for Locke-at-Broken-Wharf. They have a small fridge, a two burner hob and combo oven/microwave.
https://www.lockeliving.com/en

For the past several years, I have visited my family in early June. This is one of my favorite times to visit. Flowers are in bloom and the chance of fair weather is reasonably good. This past summer (June 10 -14), temperatures did get into the 80s for a few days, but it felt comfortable. London with all the city buildings and the underground will of course always feel hotter. I returned to the UK in September. We had a week or more of good weather again (80 degrees). Nights seemed a little cooler.

I would avoid the end of July and all of August. Schools are out for their summer holidays and it is peak European travel time. Also, the chances of a heatwave are greater during these months. A few years ago, (2019) we were in Cambridge on one of the hottest days ever (100 degrees). The heatwave, lasted about a week and it was miserable without air conditioning. However, apparently, July and August were a washout this past year. You just never know.

Why not try an appartment?

The last five times we have been to London we have stayed in an appartment. We enjoy the option to have a prolonged breakfast. Usually at least two hours, where we chill, read (online) news, and talk about our plans for the day. Lunch is always eaten where we find ourselves, when we get hungry. Dinner is sometimes in a restaurant, but mor and more frequently at "home"; either cooking or heating some "ready meals".

We have used Booking.com or VRBO.com to find a place.

Given your concerns about temperature, I wanted to highlight this: note that air conditioning isn’t as common in London as you might expect. If it’s important to you, make sure your accommodation has it. Some of the older hotels - particularly on higher floors - can get very hot.

If choosing an apartment, an “aparthotel” in a modern purpose-built building is more likely to be air conditioned. AC is very rare in private homes or older buildings in London. And the last few summers have had periods of weather well into the 80s. However that does tend to be June/July and by later August things will often be cooler.

Adding to Golden Girls recommendations, I would be careful of staying in a lower floor/basement flat that doesn’t have A/C, too. We did this past end of June and were pretty uncomfortable at night sleeping. It wasn’t because the temperatures outside were too bad, (a couple of days hit low 80s) but more due to the fact that because the windows were locked/bolted shut, there was no circulation. With three fans running, we tried to minimize the stagnant humid air, but it was sauna like for for awhile upon entering the place after a long day sightseeing. I know finding air conditioning in London flats is difficult, but if I were to go that route again in the summer, I would try to find one with A/C or definitely find one on a higher floor where we could take advantage of the cooler night temperatures by opening the windows for circulation. Just food for thought!