Stephen Vincent, an amateur weather watcher from Sheffield, has created The Washing Line Index website. The site uses live forecast data to assess drying conditions across the UK, aiming to answer the question of whether it is a good day to put washing out.
The website offers a "shirt rating" and a drying score out of 100. It provides separate morning and afternoon forecasts, based on factors such as sunshine, rain, humidity, and wind. Vincent stated that the system works in the background from live weather data, computing it into a score.
The idea developed from Steel City Skies, a Sheffield weather page Vincent previously ran. He said the new site aims to provide straightforward forecasts without technical jargon or "sensationalism." The informal shirt system, which rates days out of five shirts for suitability, was a popular feature that prompted the creation of the standalone tool.
Users can enter their postcode to receive a score. Vincent noted that challenges included deciding the importance of each weather factor, as humidity can slow drying even on warm days, and rain timing can affect its impact. The highest ratings are typically achieved when sunshine, a steady breeze, low humidity, and very little risk of rain align.