So, no rain or cooler temperatures anymore? I knew climate change was bad, I didn't know it reached apocalyptic levels already.
The problem is that high demand periods (i.e. for air conditioning) correlate with conditions (high temperatures) that are making the nuclear plants difficult to operate.
It doesn't matter so much for the summer demand if nuclear runs at full capacity in cold weather. Part of the issue is that these plants are using rivers for cooling, which by definition have less thermal mass than larger bodies of water like oceans.
The long term issue is that climate change is pushing these river temperatures consistently higher over time.
One of the reasons why nuclear goes so well together with renewables like PV. Actually said that we have more coal plants than nuclear ones in Germany. But that is hibdsight, at the time the decisions were almost reasonable.
To the contrary, they have had to scale back nuclear because the rivers they use for cooling are too warm [1].
And they have resorted to importing power:
"That means France is importing power at a time it would normally be exporting it and EDF is buying electricity at high market prices, just as Europe is scrambling to find alternative energy supplies to Russia."
1. https://www.reuters.com/business/energy/warming-rivers-threa...