Hotter still is the core. In the sun this is thought to be 10 - 20 million degrees. These temperatures are due to the pressure caused by gravity trying to compress the star. It has to be this temperature for fusion of hydrogen to take place. Once fusion starts in a young star this adds to the temperature to ensure that fusion continues.
Weather in Lisbon in September. The average maximum daytime temperature in Lisbon in September is a warm 27Â°C (81Â°F) with low heat & humidity. There are usually 9 hours of bright sunshine each day, which represents 68% of the 12 hours of daylight. The average sea temperature in and around Lisbon in September is 19Â°C (66Â°F). Expect 26mm (1.0 inches) of rainfall across the whole of September with 6 days with some rain falling. Maximum UV levels will be high (6 UV index) at midday when the skies are clear.
What's the best time to go to Lisbon in Portugal? Here are some annual weather facts we collected from our historical climate data: On average, the warmest month(s) are July and August. Most rainfall (rainy season) is seen in November and December. Lisbon has dry periods in June, July and August. On average, the warmest month is July. On average, the coolest month is January. December is the wettest month. This month should be avoided if you don't like too much rain. July is the driest month. Do these climate conditions match with when you want to go to Lisbon in Portugal? Get a great hotel deal here (and this way we get a commission and we are able to keep this website free for everyone). For more information, see the weather forecast and our average climate infomation (by month in graphs) below. * Data from nearest weather station: Lisbon, Portugal (0.0 KM).