You didn't ask any questions, but there is enough information here to determine how hotter or colder the temperature has become from in the morning till the afternoon.
Answer:
The weather is 20 7/8 degrees hotter in the afternoon than it was in the morning.
Explanation:
Romain notices that the temperature was -11 1/2 degrees.
This corresponds to -23/2 degrees.
In the afternoon, the temperature becomes 9 3/8 degrees, which corresponds to 75/8
This statements tells us that therm temperature has been (23/2 + 75/8) degrees hotter than it was initially.
23/2 + 75/8 = 167/8 = 20 7/8