Right answer: frío
We can know the correct word by the context. In this sentence, which is written in present, we know that the temperature is 22 degrees Fahrenheit (equivalent to -5.5 degrees Celsius). This is quite cold, in addition we know it is snowing.
Taking into account this data, we may say that today is a cold day or today is cold. In Spanish this is written as hoy hace frío.
Therefore the right answer is frío (cold).
And the complete sentence is:
Hoy hace mal tiempo. Nieva y la temperatura es 22 F hoy hace frío
Today it is bad weather. It is snowing and the temperature is 22 F today it is cold