At last we may see some higher temperatures next week reaching the mid to high twenties. It is not looking dry so we will see some heavy rain showers I expect triggering some thunderstorms.
This GEFS chart shows the temperature at 850 hpa 1,500 metre and the bottom of the graph is rainfall for the Birmingham area. At the moment around the 23rd onwards will see temperatures around the mid twenties with temperature increasing even higher during the last week of the month. It looks like there will be some heavy rainfall at times.