Passage of a depression
As the depression approaches cloud increases and it begins to drizzle. As the front gets nearer temperatures increase and the rain gets heavier. With the passage of this warm front (so called because of the rising temperatures) the weather clears up and the temperature rises further in the warm sector.
The cold front usually brings heavy rain and a fall in temperature as it passes once the cold front has passed conditions in the cold sector are unsettled, cool and often windy.
Conditions may settle for 12-24 hours as a ridge of relatively high pressure moves in separating one low pressure system from the next one over britain, often about 24 hours later.
Anticyclones, or high pressure systems, often bring clear skies and fine weather. This can last for days or even weeks.
Summer and winter bring different types of conditions. In summer anticyclones are associated with heat waves, when temperatures may exceed 25'c. In winter they may bring cold, clear conditions with night frosts and fog. In large cities they may also result in smog because of the chemical reaction between exhaust fumes, trapped by the cold, heavy and stationary air and sunlight.