A pressure dome wedged over Britain will drive another week of cloudy calm before a crack in its armour ushers the first taste of winter. Stubborn high pressure behind the settled, gloomy weather shows no signs of weakening through into mid-month. Rainless, still skies will persist after the weekend, although a ‘cleaner’ pattern will see mist and murk replaced by sunshine and above-average temperatures. But a chilly change is afoot, with easterly and north-easterly winds threatening to end the balmy spell with bitter nights, frosts and even snow. James Madden, forecaster for Exacta Weather, sa…