Contributors xiii
Foreword xiv
Preface xv
Acknowledgements xvii
Acronyms xviii
1 Mean Climate and Seasonal Cycle 1
1.1 Introduction 1
1.2 Rainfall and Evaporation Climatologies 3
1.3 Water Vapour and Clouds 12
1.4 Radiation, Dust, Sunshine Duration, Vegetation and Soil Water 14
1.5 Pressure, Temperature, Humidity and Wind at the Surface 18
1.6 Upper Air Wind, Mass and Humidity Fields 22
1.7 Summary Schematics of the January and July West African Monsoon System 33
2 Synoptic Systems 40
2.1 Scientific Background 40
2.2 Operational Methods and Canonical Synoptic Patterns 71
3 Deep Convection 90
3.1 Scientific Background 90
3.2 Operational Methods 115
4 Local Weather 130
4.1 Scientific Background 130
4.2 Operational Methods 160
5 Dust 175
5.1 Scientific Background 175
5.2 Operational Methods 188
6 Nowcasting 204
6.1 Scientific Background 204
6.2 Operational Methods for Nowcasting Severe Weather 221
7 Subseasonal Forecasting 255
7.1 Scientific Background 255
7.2 Operational Methods 277
8 Seasonal Forecasting 289
8.1 Scientific Background 289
8.2 Operational Methods 316
9 Remote Sensing 323
9.1 Scientific Background 323
9.2 Operational Methods 362
9.3 Case Study, Presentations and Other Resources 373
10 Numerical Weather Prediction over Africa 380
10.1 Scientific Background 380
10.2 Operational Numerical Weather Prediction over Africa 397
11 West African Synthetic Analysis and Forecast: WASA/F 423
11.1 Introduction 423
11.2 The intertropical discontinuity/intertropical front, or intertropical boundary in Ghana 425
11.3 The Heat Low or Thermal Depression 426
11.4 The Subtropical Jet 429
11.5 Features Associated with Mid?]latitudes 430
11.6 Mid?]level Dry Air 431
11.7 The Tropical Easterly Jet 431
11.8 The African Easterly Jet 433
11.9 African Easterly Waves and Cyclonic Vortices 435
11.10 The African Monsoon Layer and the Monsoon Trough 441
11.11 Dust or Sand 444
11.12 Convection 444
