In May, in Lake Garda, Minimum temperatures vary between 13 in the morning and 24 in the afternoon. The average rainfall is around 106 inches, for 16 days without rain. Check the weather over the last 5 years for the dates of your stay As for the water temperature: Lake Garda is a lake fed from mountain water and it is deep. So it is cold. Statistic says, in May the water temperature is an average about 17 degree celsius, but can be in some special sheltered bay to 21 degrees. Reply. Report inappropriate content. Amethyst-2009. Water temperature in Garda lake in April. Is it warm enough to swim in Garda lake in April? Average water temperature in Garda lake in April is 13.8°C and therefore is not suitable for comfortable swimming. The warmest water in Garda lake in April is 19°C, and the coldest is 9°C. To find out the water temperature today and in the coming days The average temperature in October in Lake Garda is 13°C, with highs of 17°C and lows of 10°C. Typically there’s around 6 days’ worth of rainfall in October, which is lower than in April, May & June. Lake Garda enjoys a higher temperature than the rest of Northern Italy as it’s protected from the colder climate by the surrounding Average lake surface temperatures in September range from around 70-75°F (21-24°C), with the warmest areas being along the southwest shores. These balmy late-summer water temperatures result from Lake Garda’s unique geographic features and temperate Mediterranean climate. June is one of the best months to experience Lake Garda’s optimal weather conditions with average temperatures hitting 21°C (70°F), while the monthly high is 26°C (79°F) and the monthly low is 15°C (59°F). Plus, the height of June and the summer solstice gives tourists 9 hours of sunlight, and, on average, only 12 days of rainfall. The first month of the autumn, September, is also an agreeable month in Garda, Italy, with an average temperature varying between 13.8°C and 21.9°C. Temperature The commencement of September includes a gentle temperature shift, with the average high-temperature dropping a bit from a moderately hot 26.4°C in August to a pleasant 21.9°C. Get the monthly weather forecast for Bellagio, Lombardy, Italy, including daily high/low, historical averages, to help you plan ahead. QJR4.