If the daily air temperature is between 0 °C to 14 °C, what sort of temperature would be found within caves? Will it be any colder or warmer? The caves in question (Wombeyan) do not go terribly far underground.
The temperature within the cave is almost constant whatever the current surface temperature is.
Once well away from surface influences, i.e., not near an entrance or another close connection to the surface, where air movements can influence the temperature, caves are usually at the same temperature (or very close) as the annual average temperature for the cave's location all year round.