Well, wear a denim jacket in cold weather will give you warmth will depend on the thickness and lining of the jacket, as well as the layering you choose to do underneath.

And Denim Jackets alone are generally not as warm as heavy winter coats or jackets specifically designed for cold weather. However, you can still wear a denim jacket in colder temperatures by following these tips:

1. Layering: Wear thicker layers underneath your denim jacket to add warmth. Opt for sweaters, hoodies, or thermal tops to provide insulation.

2. Scarves and Accessories: Add accessories like scarves, gloves, and hats to protect your neck, hands, and head from the cold.

3. Insulated or Lined Denim Jackets: Look for denim jackets with added insulation or lining. Some denim jackets may have a quilted or fleece lining, which can provide extra warmth.

4. Layering with a Coat: If the weather is extremely cold, you can layer your denim jacket under a heavier coat or jacket for added warmth. This way, you can enjoy the style of the denim jacket while still staying cozy.

5. Smart Fabric Choices: Consider denim jackets made from thicker, heavyweight denim fabrics, as they tend to provide more warmth compared to lighter denim options.

It's important to note that while denim jackets can provide some insulation, they may not be suitable for extremely cold or harsh weather conditions. In such cases, it's recommended to prioritize your comfort and safety by opting for a jacket specifically designed for cold weather.