It will be very light in Espoo during 8-17 June. The sun rises at 3:56 and sets at 22:41 on the 8th and the day is actually getting even 15 minutes longer during the races. This is the only thing you can take for granted on weather in June.
We have a lot of warm days, but it can be rather chilly as well. The seawater temperature is rising rapidly but averages only 10-15 deg Celsius during that period. The air temperature at sea is around 15 deg C. According to the wind statistics for June in Espoo the are 10 days with winds in excess of 10m/s and one storm day when we would not sail. However last year we had 14 days of wind in excess of 10 m/s. The prevailing winds are SW. The average wind is N-NW 5 m/s for the morning which dies out at noon time and is followed by 5-10m/s SW Seabreeze in the afternoon.