My car said that the temperature was 32 degrees, but it is foreign built and seems to have its own microclimate based on continental weather patterns, so that in winter the reading plunges down to minus ten and beyond. I'm sure that it wasn't hotter than 23.
We decided to drive to Birling Gap, a typically pebbly Sussex beach that redeems itself with sand and rockpools at low tide. It was reasonably crowded, but I wasn't bothered. Once, a beach was synonymous with quietude and my idea of bliss was to lie down and listen to the waves, but in the post-children world, my ambitions are broken. If nobody drowns or gets lost, then it's a good day out.
The other people on the beach seemed to be mostly families but there were also quite a few young Eastern Europeans, possibly landlocked, in search of an end to things.
I looked at the other parents. There were many men with tattoos, beer bellies and small breasts, whose feral appearance belied their tenderness with their children. There were also middle-class couples who all wore sunhats and sensible clothes, dishing out fresh fruit for lunch ("Who wants some melon?" "Me, me, me!"). Where did I fit into it all?
When I was planning the trip, I envisaged a montage of happy memories with me in the starring role as the fun dad. But I was rubbish. I complained when my oldest son kicked sand all over me, felt profoundly bored when we were paddling in sea and got frustrated when nobody seemed willing to look at a rock pool for more than two seconds.
I was tired. I'd had a difficult week and although I thought I'd successfully compartmentalised the crappy bits of my life, it was increasingly clear that I hadn't. I decided to go for a walk.
Amazingly, it only took less than a quarter of an hour of scrambling over boulders and wading through rockpools before I was completely alone. You would think that a beach that is in one of the most densely-populated parts of England would be completely packed on this, the first hot weekend of the year, but instead I felt like Charlton Heston at the end of Planet of the Apes.
When the tide comes in, the beach disappears and it was disconcerting being completely alone in this transient landscape, as if I was at the end of things. It seemed so strange that there was no evidence of the human world, even though it was less than a mile away. But I was also grateful for the herd instinct that makes most people huddle together, leaving wide open spaces for those of us that need them.
I started walking back and was surprised to feel a sense of relief when I saw people again. A group of Russians were picnicking on some huge, limestone boulders that looked as if they had been arranged like seats. Further on, a rather suspicious-looking man in his late 50s sat alone, taking pictures of people on a camera with a very long zoom lens. I watched his camera follow the path of two adolescent girls in bikinis and wondered if I was jumping to conclusions about his motivation.
In the distance, I saw my sons playing a ball game with my wife and her friend. They looked happy and relaxed, with the glow of people who had been outdoors for a few hours. Earlier I'd been wondering what I had achieved in my life.
Here was the answer.