Winters in Ruislip are typically cool, with January and February averaging around 4-6°C, while December is similar. Mornings can be chilly, but temperatures rise to more pleasant levels by afternoon, occasionally reaching up to 14°C. As spring approaches, March marks a turning point with average highs of 7°C, though it's not uncommon for temperatures to fluctuate wildly between -4 and 23°C. Summer brings warmth, with June and July often seeing highs above 20°C, while August can be slightly cooler. Autumn is generally mild, with September and October experiencing temperatures ranging from 6-28°C and 4-19°C respectively, though mornings are typically crisp.