I love how much you are aware of the changing seasons out of the city; there are numerous beautiful forests around Hertfordshire to go for a run, a walk or have a picnic. One of the best destinations for a day out from London might be Northaw Great Wood. The main entrance is located on the Ridgeway, the B157 from Cuffley to Brookman's Park.
London has great green spaces. There are large royal parks and small public gardens, hidden allotments and roof terraces. Each one has its own identity and characteristics and everyone has their favourite. In summer they become extensions of people homes, you see girls sunbathing from 9 am and the endless picnics mean you can eat 3 meals a day in the park. My favourites - St James Piccadilly Gardens, Hyde Park, Barbican Conservatory.
There's something about this street, probably the fact that it's pedestrianised, that makes it feel like holidays. It also has a solid range of bars (Cafe Kick), restaurants (Berber & Q) and cafes (Brill) so is a good option for all times of the day. They have a quality variety of street food vendors operatin during the day, and fairy lights help it to come alive at night
Warm summer nights should be spent in the high grass in Hampstead Heath above the ponds. For midsummer bring herring, snaps and songs and stay until sunrise!