About the Temperature and Clothing in Spring (March–May) on the Main Island of Okinawa

The average temperature in March is about 19°C. In the first part of the month, when the north wind blows, the perceived temperature feels lower, so cardigans and hoodies are useful. Beaches open between mid-March and early April. During the day, when you can comfortably wear short sleeves, the sun is strong, and UV levels are comparable to July in the Kanto region. Sun protection is necessary. In mid-March, the "Yachimun Market," the largest pottery market in Okinawa Prefecture, is held in Onna Village. There are plenty of events, such as the "Ryukyu Kaiensai" fireworks festival in Ginowan City, where 10,000 fireworks are launched, and the "Okinawa International Movie Festival" which begins across the main island. Around Golden Week, when the "Haarii" sea festival, which has a history of about 600 years, takes place, the average maximum temperature exceeds 25°C, making it humid and hot enough to sweat even in short sleeves.
The rainy season usually begins around May 10th, and it is characterized by short bursts of torrential rain, so it is a good idea to carry a compact raincoat or towel. It is also recommended to spend time relaxing in a cafe to wait out the rain.

About the Temperature and Clothing in Summer (June–August) on the Main Island of Okinawa

The unsettled weather of the rainy season continues until late June. After that, the weather clears up, making it perfect for marine leisure. You can enjoy ocean activities at unique Okinawa marine spots, such as snorkeling in the Blue Cave in Onna Village or swimming at Kouri Island, a remote island surrounded by emerald green waters. The average temperature in July and August is about 29°C. From mid-July onwards, when typhoons may approach, humidity rises and it becomes more sultry. Breathable clothing such as Kariyushi wear or linen dresses is recommended. Since UV levels also peak, be sure to take thorough sun protection measures.
Speaking of summer traditions in Okinawa, there is the Obon event called "Eisa." You can see "Michi Junee," a memorial service for ancestors where people walk through each village dancing to the sound of drums and finger whistles. On the first Sunday of August, the large-scale "Summer Festival in Naha: 10,000 Eisa Dancers" is held.

About temperatures and clothing in autumn (September–November) on Okinawa Main Island

Even in September, Okinawa remains a tropical paradise. As the number of typhoons approaching is similar to August, sultry days continue. Breathable clothing is still sufficient. You can still enjoy leisure activities at the beach. By October, the heat subsides. The average temperature is about 25°C, and in November it is about 22°C, making it comfortable to spend time. However, the sea breeze shifts to the north and it starts to feel cool in the mornings and evenings, so have a light outer layer like a cardigan or hoodie ready.
October and November have little rain, making them the perfect seasons for driving and sightseeing. It is a great time for a journey of exploration, such as strolling through Kokusai-dori or the Naha City First Makishi Public Market, or visiting the ruins of the ancient Ryukyu Kingdom. Visiting power spots such as Sefa-Utaki, a place of prayer and a World Heritage site, and Kudaka Island, the island of the gods, is also recommended.

About temperatures and clothing in winter (December–February) on Okinawa Main Island

The average temperature in December is 18.4°C. While this is comparable to May in Tokyo, the northerly winds make it feel more like late October to early November in Tokyo. You will need a sweater or a light outer layer for the mornings, evenings, and at the beach. January in Okinawa is cherry blossom season. From mid-January to early February, the cherry blossom front moves from the north to the south, and you can see deep pink Kanhizakura (Taiwan cherry) blossoms in various places. The average temperature during this period is 16.5°C. As in December, be sure to carry a windproof coat. February, bustling with professional baseball training camps, is as warm as May in Tokyo. While there are days when you can spend time in short sleeves during the day, it is often cloudy, so it is safe to have a hoodie or similar item on hand.
In winter, be sure to visit the northern area of Okinawa. You can fully enjoy Okinawa's unique nature, such as whale watching, the Churaumi Aquarium, and the Yanbaru Forest. Since many famous cherry blossom spots are concentrated in the north, you can also enjoy cherry blossom viewing.