Sounds like Portland, Oregon weather.
Or like the weather in Seattle, Washington. Right?
The truth is, the few days before the opening ceremonies were in the 80s. But just like the Pacific Northwest, hot and sunny days can be challenging to find–even in summer.
I still remember a summer visit to London. I wore a jacket and we actually had to buy umbrellas (they were overpriced!) because it rained on each of our three days in the city.
What London Weather Is Like, On Average, At This Point In The Summer vs. Seattle & Portland
London Average High Late July & Early August: 73 degrees F / Portland is 82 / Seattle is 77)
London Sunset on July 28: 8:54pm / Portland is 8:43pm / Seattle is 8:48pm
London Days With Rain Each Year: 155 / Portland 153 days / Seattle 155 days
Forecast for the entire run of the London games? Yep, this is it. Found it but long range forecasts like this are notoriously at risk of changing. Accuweather has the updated information in one easy to view place.
And now we know the truth. London weather is a lot like Portland and Seattle in the summer–except cooler!