Although weather is just one factor, it can really affect your travel plans, especially when you're planning an extended stay in Parnell. The hottest months are usually July and August, with an average temperature of 23°C, while the coldest months are January and February, with an average of 0°C. The snowiest months in Parnell are January, November, February and December, with each month seeing an average of 13 cm of snowfall.