The Simple Answer :   The color of a star's visible light indicates its surface temperature: a relatively cool star glows red (longer wavelength), and very hot ones glow â¦ bluish-white or even blue (shorter wavelengths).
Over the course of the year, the temperature in Shetland typically varies from 37Â°F to 59Â°F and is rarely below 30Â°F or above 63Â°F. The warm season lasts for 82 days, from June 24 to September 14, with an average daily high temperature above 55Â°F. The hottest day of the year is August 6, with an average high of 59Â°F and low of 52Â°F. The cool season lasts for 133 days, from November 26 to April 8, with an average daily high temperature below 46Â°F.
September's weather is a lot like July and August, only a bit cooler. Temperatures typically range between 55 degrees and 70 degrees and average precipitation during the month is 3.7 inches. It gets a little cooler later in the month, so bring along a light jacket.