Weather in Caernarfon by month: what to expect

The weather in Карнарвон is mild but changeable year-round, typical of coastal Wales. Winters are cool, with temperatures rarely dropping below 4 °C, while summers remain gentle, rarely exceeding 19 °C. Rainfall is spread across the year, though October and December tend to be the wettest months.

Visitors to Карнарвон will find the most settled weather between May and August, when days are longer and sunshine averages around 6–8 hours. Even in these months, light rain is common, so packing layers and waterproof gear is wise. The shoulder seasons, April and September, offer quieter travel with similar temperatures to summer but fewer crowds.

In Карнарвон, temperatures rise gradually from winter to summer. January is the coldest month, with averages around 6.7 °C and lows near 4.4 °C, while August is the warmest at 16.4 °C, though nights can still dip to 13.7 °C. The difference between day and night temperatures is modest, rarely exceeding 5 °C even in summer.

Spring and autumn in Карнарвон bring mild conditions. By April, daytime highs reach 12.9 °C, and by May, they climb to 16 °C. September sees temperatures around 14.9 °C, cooling to 12.3 °C in October. These seasons are ideal for exploring the town and nearby landscapes without the extremes of winter or summer heat.

Rainfall in Карнарвон is consistent, with no truly dry season. The wettest months are October and December, each averaging over 100 mm of rain. Even in the driest months, April and May, showers are frequent, with around 40–50 mm of precipitation.

The town’s coastal location means rain can arrive quickly, often in short bursts rather than prolonged downpours. September marks the start of the wetter period, with rainfall increasing from 98 mm to over 100 mm by December. Visitors should prepare for rain at any time of year, though June and July are slightly drier than the rest.

For a trip to Карнарвон in winter, pack warm layers, a waterproof jacket, and sturdy footwear. Temperatures hover around 6–8 °C, and rain is common, so a hat and gloves are useful for windy days. Waterproof trousers can be helpful if you plan to hike or spend time outdoors.

In summer, lightweight clothing is suitable for daytime, but evenings can feel cool, so a light sweater or fleece is advisable. A compact umbrella or waterproof shell is essential, as rain is always a possibility. For spring or autumn, layering is key—light jackets, long sleeves, and a scarf will help you adapt to shifting conditions.

Regardless of the season, comfortable walking shoes are a must in Карнарвон. The town’s cobbled streets and nearby trails are best explored on foot, and rain can make surfaces slippery. A small backpack for layers and rain gear will keep you prepared for whatever the weather brings.