First, don't be embarrassed. I've learned not to laugh at anything a customer tells me.
If you've noticed it enough times to ask the question, it's worth paying attention to.
And yes...temperature absolutely can affect how a vehicle behaves.
Cold air is denser than warm air, which changes how the engine breathes. Transmission fluid is thicker when it's cold and thinner when it's hot. Sensors, electrical connections, and even battery performance can all change with temperature.
Now, the fact that it happens at night may not actually mean it's because it's dark. It may simply be because it's cooler outside.
I've diagnosed vehicles that only acted up on cold mornings, only after sitting in the sun all day, or only after towing for an hour. Those conditions matter because they change the environment the vehicle is operating in.
That said, I also wouldn't automatically blame the temperature.
I'd want to know:
Does it happen every night or only when it's cooler?
Does it happen in the summer too?
Is the transmission actually shifting differently, or does the engine just feel more responsive?
Are you driving the same route at the same speed each time?
One thing I've learned is this:
Vehicles don't have coincidences—they have conditions.
If you can identify the condition that makes the problem appear, you've already given your technician one of the biggest clues they'll ever get.
So no, I don't think your question sounds ridiculous at all. Sometimes the smallest pattern is exactly what leads us to the real problem.