Planning for the weather is an important factor for making your trip to Le Grand-Bornand a success, especially when you're splurging. The hottest months are usually July and August, with an average temperature of 14°C, while the coldest months are January and February, with an average of -2°C. The snowiest months in Le Grand-Bornand are October, September, May and December, with each month seeing an average of 14 cm of snowfall.