Brief Answer:
Yes,it is due to cold diuresis which is very much normal.

Detailed Answer:
Hello XXXXXXX
Welcome to health care magic,

In cold climates, our body tries to keep our core warm by constricting blood vessels and reducing the flow of blood to the skin.

This process is called vaso-constriction which is necessary because heat is lost from our skin into the environment, so our body reduces the flow of blood to our both extremities.(to keep them warm in cold)

Because of this constricted blood vessels, our blood pressure tends to rise and to regulate the blood pressure, our kidney filters out excess fluid from the blood to reduce its volume causing excess urine formation.

As our bladder fills up with the excess of urine, we feel the urge to urinate.

Also, full bladder is another way that your body loses heat, so we keep urinating frequently which helps to preserve core warmth.

In contrary to this, when the weather is hot, our body system tries to keep body cool by evaporating the water along with unwanted things through the skin in the form of perspiration.

Therefore by this way, skin helps the kidney by sharing its work of cleaning the body in hot weather conditions through perspiration.

In cold conditions, there is no perspiration or very less perspiration (due to cold weather itself) and the kidney has to bear the entire burden and hence we urinate frequently.

These are the reasons we urinate more and frequently in cold climates.

Hope this simple and detailed explanation will be helpful.

Regards,

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