Intermittent - sounds like a cat caught under the

From what you have described I believe what you have is intermittent belt squeal in the serpentine belt. These tend to squeal in cold and damp weather and usually the noise will typically dissipate once the belt warms up from friction and radiated engine heat. (This is not always the case however).

You should check the belt for age and wear and, if in doubt, replace it as these are quite inexpensive items which need periodic replacement in any event. Also make sure the current belt - and any replacement - is properly aligned on the pulleys.

If you have no record of when the belt was last changed I would replace it even if it looks ok. These are easy and quick for an experienced person to replace.

Often when you replace the serpentine belt the squeal will disappear but return again as the new belt "wears in".

There are some temporary fixes for noisy belts which sometimes work (such as removing it and lightly spraying the belt with "Belt Grip"). There are also 1 or 2 others but I would not recommend them.