The best time to go to Lake Oswego is during the summer months, from June to August, or in the shoulder seasons of late spring (May) and early fall (September).During the summer, Lake Oswego experiences warm, dry weather with average temperatures in the 70s Fahrenheit, making it ideal for outdoor activities. The lake itself is a focal point, with opportunities for boating, paddleboarding, and swimming. Many local events, such as farmers' markets and outdoor concerts, take place during this period. Couples often appreciate the extended daylight hours and the ability to enjoy waterfront dining and leisurely strolls along the lake.May and September offer pleasant weather that is typically milder than the peak summer, with fewer crowds. Temperatures usually range from the high 50s to low 70s Fahrenheit. These months are excellent for enjoying the area's parks and trails, such as those around Tryon Creek State Natural Area, without the intense heat.