This GEFS graph is showing that we will have some very warm temperatures this week with the temperature falling away after Thursday 8th September. This graph runs from 5th to 20th September,
This GEFS 850hpa graph shows the temperature at 1,500 metres. The bottom line is rainfall. So by looking at the graph we can see the temperature remains around 15 centigrade until the 9th when it drops away sharply.
After the 8th September we see a yo-yo in temperatures but you can see they never recover to 15 centigrade again so some days will feel quite cool.
At this time of the year 15 centigrade at 1500 metres is approximately 23-25 c at ground level.
The bottom of the graph shows that we will have a period of rain showers from around the 10th to 14th.