Yesterday was the highest temperature of the year at 29.2 degrees Celsius.

Today it is raining, has been pouring since a little after 6 am, is forecast to heavily rain with Thunderstorms this afternoon!

The high will only be 23 today, with a low tonight of 19!

The Shanghai meteorological bureau said to bundle up as it is easy to get a cold this time of year!

Laughing - the Air Conditioner was on yesterday so no doubt about it!

Then there is this:

Thunderstorms and wind gusts of more than 30 kilometers an hour are expected this afternoon.

According to the solar calendar, Monday was the beginning of summer. However, the bureau waits until the daily average temperature is more than 22 degrees for five straight days before it says summer has begun.

Summer usually begins in the last 10 days of May. Last year summer started on May 13, the earliest since 1873, according to the bureau's statistics.

http://www.shanghaidaily.com/article/?id=358778&type=Metro

I cannot get the link to work, so I am including it for now as text.