1. Mid-latitude Climates

2. Marine West Coast Climate

4. UK Air Masses Air mass types m = maritime, wet c = continental, dry
P = polar, cold
T = tropical, warm A mP cP mT cT

5. UK Weather
Westerly Unsettled weather with variable wind directions as depressions cross the country. Mild and stormy in winter, generally cool and cloudy in summer (mP, mPw, mT).
NW Cool, changeable conditions. Strong winds and showers affect windward coasts especially, but the southern part of Britain may have dry, bright weather (mP, mA).
Northerly Cold weather at all seasons, often associated with polar lows. Snow and sleet showers in winter, especially in the north and east (mA).
Easterly Cold in the winter half-year, sometimes very severe weather in the south and east with snow or sleet. Warm in summer with dry weather in the west.' Occasionally thundery (cA, cP).
Southerly Warm and thundery in summer. In winter it may be associated with a low in the Atlantic giving mild, damp weather especially in the south-west or with a high over central Europe, in which case it is cold and dry (mT or cT, summer; mT or cP, winter).
Cyclonic Rainy, unsettled conditions often accompanied by gales and thunderstorms. This type may refer either to the rapid passage of depressions across the country or to the persistence of a deep depres­sion (mP, mPw, mT).
Anticyclonic Warm and dry in summer, occasional thunderstorms (mT, cT). Cold and frosty in winter with fog, especially in autumn (cP).

6. Effect of wind direction and topography on rainfall in England and Wales

7. Air masses in N. America

8. North American rainfall
Westerlies bring damp air, uplift by Rockies.
Warm damp air from Atlantic. Hurricanes.
Sub-tropical high, descending, dry air.
Wind from east.

9. Mid-latitude Cyclones

11. Warm Front
precipitation

12. Cold Front
Cold air
Warm air
Note difference in wind direction and how cold air advances under the warm sector

13. Polar front

14. Mid-latitude frontal zone

15. Cyclogenesis cold air polar front warm front cold front warm air
Early stage
occluded front
Open stage
Occluded stage
Dissolving stage

16. Cyclogenesis – in cross-section

17. Conveyor belt model of cyclone

18. Mid-latitude Cyclones
Formation revisited

19. Polar front

20. Upper atmosphere pressure and winds

23. Mid-latitude Climates

24. Mediterranean Climate

25. Humid Subtropical

26. Humid Continental

27. High-latitude Climates

28. Sub-arctic Climate

29. Tundra Climate

30. Polar Climate