When planning a visit to Portmarnock, the best time to go is generally during the late spring and summer months, from May to September, for the most pleasant weather and a full range of activities.This period offers the warmest temperatures, with average highs ranging from 15°C to 20°C, and longer daylight hours, which are great for enjoying the outdoors. You'll find it ideal for activities like golfing at the renowned Portmarnock Golf Club or taking long walks along the famous Velvet Strand beach, a 5km stretch of golden sand that's popular for its views and gentle waves.For those interested in watersports or simply relaxing by the sea, July and August are particularly good, as the sea temperatures are at their highest, making swimming more inviting. It's also when local events and festivals are most likely to be taking place, adding to the local experience.If your priority is golfing, May, June, and September strike a great balance between good weather and fewer crowds on the courses.