What is wrong if the dogs nose hot then you put it outside and gets cold again?

It's perfectly normal for a dog's nose to be warm inside and cool outside.

Here's why:

* Body temperature: A dog's nose is a part of its body, and its body temperature will naturally be warmer indoors than outdoors.

* Blood flow: The blood flow to the nose can change depending on the environment. When it's cold outside, the blood flow to the nose may decrease slightly to conserve heat, making it feel cooler.

A hot nose doesn't always mean a dog is sick.

However, if you notice a persistent change in your dog's nose temperature along with other symptoms, like:

* Lethargy

* Loss of appetite

* Vomiting or diarrhea

* Coughing or sneezing

* Discharge from the eyes or nose

* Difficulty breathing

Then it's important to consult your veterinarian. These could be signs of an underlying health issue.