Extreme Weather

Robert K. Doe, BA Hons. (Exon), Ph.D. (Port), FRMetS, MRIRobert graduated with a Ph.D. from the University of Portsmouth, where he specialised in coastal storm climatology. Robert is a Director and Treasurer of The Tornado and Storm Research Organisation (TORRO). He is a Fellow of The Royal Meteorological Society (FRMetS) and Member of the Royal Institution (MRI). He was Editor-in-Chief of The International Journal of Meteorology (2002–2006) and has published research on meteorological phenomena including; tornadoes, waterspouts, floods, snowstorms, ball lightning, coastal storms, climate and risk. He is an Honorary Research Fellow in the School of Environmental Sciences, at the University of Liverpool.

• Notes on Contributors xiForeword xiiiPreface xvAbout the Companion Website xvii1 Researching Extreme Weather in the United Kingdom and Ireland: The History of the Tornado and Storm Research Organisation, 1974–2014 1G. Terence Meaden1.1 Introduction: The Early Years 11.2 International T‐Scale: Theoretical Basis 21.2.1 Hailstorm Research 31.2.2 Temperature Extremes for the British Isles 31.3 Tornado Research Organisation 41.4 The Inaugural Issue of The Journal of Meteorology 41.5 Storm‐Damage Site and Track Investigations 61.6 Birmingham Tornado of 28 July 2005 81.7 TORRO Conferences 81.8 The Future 11Acknowledgements 13Additional information 13References 13Part I Tornadoes 152 Historical tornadoes in the British Isles 17Paul R. Brown and G. Terence Meaden2.1 Introduction 172.2 Etymology of the Word Tornado 172.3 Terminology 182.4 Accuracy and Completeness of the Records 192.5 Analysis of Historical Tornadoes 202.6 Examples of Historical Tornado Reports 212.7 Concluding Remarks 30References 303 Supercell and Non‐supercell Tornadoes in the United Kingdom and Ireland 31Matt Clark and David Smart3.1 Introduction 313.2 Basic Structure and Life Cycle of a Storm Cell 323.3 Storm Mode: An Overview of Single‐Cell, Multicell and Supercell Convection 323.4 Tornadoes in Supercell and Non‐supercell Storms 363.4.1 Synoptic Situations Associated with Tornadoes in the United Kingdom 403.5 Towards a Climatology of Tornadoes by Synoptic Type 433.6 Monthly and Annual Frequencies of Tornadoes by Synoptic Type 433.7 Spatial Distribution of Tornadoes by Synoptic Type 443.8 Morphology of Tornadic Storms 463.9 Association of Supercells with Giant Hail 473.10 Case Studies of Supercell and Non‐supercell Tornadoes 483.10.1 Case 1: The Cold Front of 29 November 2011 483.10.2 Case 2: The English Midlands Supercells of 28 June 2012 513.10.3 Case 3: The West Cornwall Supercell of 16 December 2012 523.11 Concluding Remarks 55References 584 Tornadoes in the United Kingdom and Ireland: Frequency and Spatial Distribution 61Peter Kirk, Tim Prosser, and David Smart4.1 Introduction 614.2 The TORRO Database 624.3 Tornado Frequency for the United Kingdom and Ireland: 1981–2010 634.3.1 Annual Number of Tornadoes and Tornado Days 634.3.2 Season and Month of Occurrence 644.3.3 Hour of Occurrence 654.3.4 Intensities 654.3.5 Track Lengths 654.3.6 Maximum Track Widths 654.3.7 Directions of Travel 664.4 Spatial Distribution of Tornadoes in the United Kingdom and Ireland 664.4.1 Simple Mapping of the Database 664.5 Issues with Mapping 664.6 Kernel Density Mapping of Tornado Distribution 704.7 The ‘London Metropolitan’ Anomaly 704.8 The Isle of Wight and South Coast Anomaly 724.9 Concluding Remarks 73Acknowledgements 74Additional Information 74References 755 Tornado Extremes in the United Kingdom: The Earliest, Longest, Widest, Severest and Deadliest 77Mike Rowe5.1 Introduction 775.2 Earliest Tornado 775.3 Other Whirlwinds (First UK Record Only) 795.4 Longest Tornado Track 805.5 Widest Tornado Track 825.6 Severest Tornado 835.7 Largest Outbreaks 885.8 Highest Death Toll 895.9 Concluding Remarks 89Acknowledgements 89References 896 Site Investigations of Tornado Events 91John Tyrrell6.1 Introduction 916.2 Getting Started: How Site Investigations Come About 926.3 Site Investigation Methods 926.4 Site Investigation Outcomes: The Growing Understanding of UK Tornadoes 946.5 Site Investigation Experience 1016.6 Concluding Remarks 102Acknowledgements 103References 103Part II Thunderstorms and Lightning 1057 Epic Thunderstorms in Britain and Ireland 107Jonathan D.C. Webb7.1 Introduction 1077.2 Selected Epic Thunderstorm Events 1097.2.1 2–3 August 1879 1097.2.2 5–10 June 1910 1107.2.3 7–10 July 1923 1147.2.4 17–18 July 1926 1147.2.5 28–29 August 1930 1147.2.6 18–22 June 1936 1167.2.7 The West Country Thunderstorm of 4 August 1938 1197.2.8 5 September 1958 1237.2.9 22–24 June 1960 1257.2.10 8–9 August 1975 1257.2.11 13–14 June 1977 1267.2.12 25–26 July 1985 1277.2.13 24 May 1989 1287.2.14 8–9 August 1992 1317.2.15 24 June 1994 1327.3 Concluding Remarks 132Acknowledgements 132References 1328 Thunderstorm Observing in the United Kingdom: A Personal Diary of Days with Thunder 1953–2013 135Bob Prichard8.1 Introduction 1358.2 Early Observations 1358.2.1 Thunderstorm Observing 1368.3 Thunderstorms of the 1960s 1378.3.1 The ‘Days with Thunder Heard’ Statistic 1408.3.2 Back to the 1960s 1408.4 Thunderstorms of the 1970s 1418.5 Thunderstorms of the 1980s 1438.6 The Forecasting of Thunderstorms 1458.7 Back to the 1980s 1468.8 Thunderstorms of the 1990s 1478.9 The Most Recent Thunderstorms: 2000–2013 1508.10 Concluding Remarks 154References 1549 Severe Hailstorms in the United Kingdom and Ireland: A Climatological Survey with Recent and Historical Case Studies 155Jonathan D.C. Webb and Derek M. Elsom9.1 Introduction 1559.1.1 Establishment of a Tornado and Storm Research Organisation Research Database of Hail Events 1559.2 Assessing the Intensity of Hail Falls 1559.2.1 Hailstorm Intensity Scale 1559.2.2 Kinetic Energy 1569.2.3 Hailstone Size and Damage 1569.2.4 Other Factors Affecting Damage 1569.3 Annual Frequency of Hail 1579.3.1 All Significant, Damaging Hailstorms 1579.3.2 Frequency of Extreme, Destructive Hailstorms 1589.3.3 Comparisons with Continental Europe 1599.4 Seasonal Occurrence of Hail 1599.4.1 General Seasonal Incidence of Hail and Damaging Hailstorms 1599.4.2 Storms of H5 Intensity or More 1599.4.3 Comparison with the Incidence of Thunderstorms 1599.5 Geographical Distribution 1609.5.1 Storms of H2 Intensity or More 1609.5.2 Geographical Distribution of Storms of H5 Intensity or More 1619.5.3 Point Frequencies 1619.5.4 European Comparisons 1619.6 Hailstorm Characteristics 1619.6.1 Hail Swathes 1619.6.2 Radar and Hail Swathe Identification 1639.6.3 Results of Hail Swathe Analyses 1639.7 Synoptic Weather Types and Hailstorms 1649.7.1 Specific Synoptic Background to Hailstorms 1649.8 Hour‐of‐Day Distribution 1679.9 Summary of TORRO’s Overall Findings 1689.10 Twenty of the Most Severe Hailstorms 1699.10.1 1687: The Alvanley Storm 1699.10.2 1697: Remarkable Late Spring Storms 1699.10.3 1763: The Great Kent Storm of 19 August 1699.10.4 1808: The Great Somerset Hailstorm of 15 July 1699.10.5 1818: Stronsay, Orkney, 24 July 1709.10.6 1843: The Great Hailstorm of 9 August 1709.10.7 1893: Northern England and Southern Scotland on 8 July 1729.10.8 1897: The Diamond Jubilee Storm of 24 June 1749.10.9 1915: 4 July 1759.10.10 1935: 22 September (Sometimes Referred to as the ‘Great Northamptonshire Hailstorm’) 1779.10.11 1958: The Horsham Hailstorm of 5 September 1789.10.12 1959: 9–11 July (Including the ‘Wokingham Storm’) 1799.10.13 1967: The Wiltshire Hailstorm of 13 July 1819.10.14 1968: The ‘Dust Fall’ Storms of 1–2 July 1819.10.15 1983: South Coast Hailstorms of 5 June 1859.10.16 1983: Violent Hailstorms in North‐West England on 7 June 1859.10.17 1985: The Essex ‘Dunmow’ Hailstorm of 26 May 1869.10.18 1996: The Storms of 7 June 1879.10.19 1997: The Severe Storms of FA Cup Final on Saturday, 17 May 1899.10.20 2012: The Destructive English Midlands Hailstorm of 28 June 1919.11 Concluding Remarks 191Acknowledgements 193References 19310 Lightning Impacts in the United Kingdom and Ireland 195Derek M. Elsom and Jonathan D.C. Webb10.1 Lightning as a Weather Hazard 19510.2 Historical Research into Lightning 19610.3 Research into Lightning Impacts 19710.4 Annual Number of Lightning Incidents Causing Injuries and Deaths 19810.5 Lightning Injuries 19810.6 Electrical Routes by Which Lightning Causes Injuries 19910.7 Lightning Strikes to Groups of People 20010.8 Locations to Avoid during Thunderstorms 20110.9 Lightning Incidents Affecting People Indoors 20110.10 The Frequency with which Lightning Strikes a Person 20210.11 Fewer Deaths from Lightning Over Time 20310.12 Lightning Strikes to Animals 20410.13 Lightning Impacts on Aircraft and Motor Vehicles 20510.14 Increasing Awareness of the Lightning Risk 206Acknowledgements 206References 20611 Ball Lightning Research in the United Kingdom 209Mark Stenhoff and Adrian James11.1 Introduction 20911.2 Definitions 20911.2.1 Lightning 20911.2.2 Ball Lightning 21011.3 What Ball Lightning Is Not 21011.4 Ambiguity: Ball Lightning, Fireballs, Meteors and Meteorites 21111.5 Early Beliefs about Lightning and Ball Lightning 21211.6 Early Reports of Ball Lightning 21311.6.1 Ball Lightning over Land 21311.6.2 Ball Lightning over Rivers and the Sea 21411.6.3 Ball Lightning Associated with Churches 21511.6.4 Ball Lightning within Houses 21611.6.5 Ball Lightning as a Precursor to Cloud‐to‐Ground Lightning 21711.7 Interpreting Early Reports 21711.7.1 1833: Early British Opinion about the Nature of Ball Lightning by Luke Howard FRS (1772–1864) 21711.7.2 1837–1859: Sur le Tonnerre and Other Works by François Arago (1786–1853) 21711.7.3 1838: Comments on Ball Lightning by Michael Faraday Frs (1791–1867) 21811.7.4 1842: ‘On the Nature of Thunderstorms’ by Sir William Snow Harris FRS (1791–1867) 21811.7.5 1854–1868: English Translations of French Works 21911.7.6 The Late 19th Century: Ball Lightning, Spiritualism and Parapsychology 21911.7.7 1921: The Meteorological Office ‘Ball Lightning Enquiry’ 22011.7.8 1923: Survey of Ball Lightning Reports 22011.7.9 1870–1934: Speculations on the Nature of Ball Lightning 22011.7.10 1936: Does Ball Lightning Exist? 22011.7.11 1936–1937: The ‘Tub‐of‐Water’ Event and the Estimated Energy Content of Ball Lightning 22011.7.12 1937–1957: Quantum‐Mechanical and Nuclear Hypotheses for Ball Lightning 22111.7.13 1955–1972: Plasma Hypotheses for Ball Lightning 22211.7.14 1964: The Flight of Thunderbolts by Sir Basil Schonland FRS 22211.7.15 1969: Eminent UK Scientists Report Ball Lightning in Aircraft 22211.7.16 1969: The Taming of the Thunderbolts by C. Maxwell Cade and Delphine Davis 22311.7.17 1971: Ball Lightning: An Optical Illusion? 22311.7.18 1971: Micrometeorites of Antimatter? 22311.7.19 1972–1995: Crew’s Ionised Jet‐Stream Hypothesis for Ball Lightning (and Some UFOs) 22411.7.20 1974: TORRO and the Journal of Meteorology 22411.7.21 1976: A Close Encounter with a Fiery Ball Raises Questions of Ball Lightning Energy 22411.7.22 Ball Lightning as Electromagnetic Radiation 22411.7.23 Reviews of Ball Lightning 22511.7.24 Ball Lightning Reported at Cambridge University 22611.7.25 1985–1999: The TORRO Ball Lightning Division 22611.7.26 1999: Ball lightning: An Unexplained Phenomenon in Atmospheric Physics by Mark Stenhoff 22711.7.27 2002: Royal Society Theme Issue on Ball Lightning 22711.7.28 2006: Publication of Ministry of Defence: Unidentified Aerial Phenomena in the UK Air Defence Region (2000) 22711.7.29 2000–2014: TORRO Ball Lightning Division 22811.8 A Selection of Ball Lightning Reports Recorded by TORRO 2000–2014 22811.8.1 Ball Lightning inside Houses 22811.8.2 Experienced Observer 22911.8.3 Earthquake Ball Lightning? 22911.8.4 A Recent Ball Lightning Event Reported to TORRO 22911.9 2014: Ball Lightning in the UK Media 23011.10 Concluding Remarks 230Acknowledgments 230References 230Part III EXTREMES 23512 Forecasting Severe Weather in the United Kingdom and Ireland 237Paul Knightley12.1 Introduction 23712.2 Modern Forecasting 23812.3 Severe Storm Forecasting in the United States 23812.4 Severe Storm Forecasting Elsewhere 23912.5 Forecasting Techniques 23912.6 The Ingredients‐Based Approach 24012.6.1 Moisture 24012.6.2 Instability 24012.6.3 Lift 24012.6.4 Wind Shear 24012.7 TORRO’s Forecasts 24112.8 Forecasting Severe Weather: 28 June 2012 24112.8.1 Background 24112.9 Concluding Remarks 245Acknowledgements 246References 24613 Extreme Flooding in the United Kingdom and Ireland: The Early Years, ad 1 to ad 1300 247Robert K. Doe13.1 Introduction 24713.2 Sources of Evidence 24713.3 The Early Years – 1st–10th Centuries 24813.4 Extreme Flooding in the 11th Century 24913.5 Extreme Flooding in the 12th Century 25013.6 Extreme Flooding in the 13th Century 25113.7 Concluding Remarks 259Acknowledgements 259References 25914 Extreme Rainfall and Flash Floods in the United Kingdom and Ireland: Synoptic Patterns and Selected Case Studies 261John Mason, Paul R. Brown, Jonathan D.C. Webb, and Robert K. Doe14.1 Introduction 26114.2 Severe Dynamic Rainfalls 26114.3 Hybrid Rainfalls – Dynamic Precipitation with Embedded Convective Cells 26414.4 Severe Convective Rainfalls 26914.5 Gwynedd, North Wales, UK, 3 July 2001 27014.6 Boscastle, Cornwall, UK, 16 August 2004 27214.7 Holmfirth, Yorkshire, UK, 29 May 1944 27414.8 Ottery St. Mary, Devon, UK, 30 October 2008 27814.9 Concluding Remarks 280Acknowledgements 281References 28115 Heavy Snowfalls Across Great Britain 283Richard Wild15.1 Introduction 28315.2 Definitions 28315.3 Synoptic Systems and Heavy Snowfalls 28315.4 Snowfall Climatology of Great Britain 28415.5 Sources of Data 28415.6 Snow Depths and Days with Snowfall 28415.7 Spatial Methodology for Heavy Snowfall Events 28515.7.1 LWT Catalogue 28515.8 Heavy Snowfall Events over Great Britain 28515.9 Heavy Snowfalls 1861–1869 28615.9.1 20 February 1865 28615.10 Heavy Snowfalls 1870–1879 28615.11 Heavy Snowfalls 1880–1889 28615.11.1 18–19 January 1881 28615.12 Heavy Snowfalls 1890–1899 28715.12.1 9–13 March 1891 28715.13 Heavy Snowfalls 1900–1909 28715.14 Heavy Snowfalls 1910–1919 28715.14.1 11–12 January 1913 28715.15 Heavy Snowfalls 1920–1929 28815.15.1 25 December 1923 28815.15.2 15–16 February 1929 28815.16 Heavy Snowfalls 1930–1939 28815.17 Heavy Snowfalls 1940–1949 28815.17.1 26–30 January 1940 28815.17.2 18–20 February 1941 28815.17.3 26–27 March 1941 28915.18 Heavy Snowfalls 1950–1959 28915.18.1 8 February 1955 28915.19 Heavy Snowfalls 1960–1969 28915.20 Heavy Snowfalls 1970–1979 28915.21 Heavy Snowfalls 1980–1989 28915.22 Heavy Snowfalls 1990–1999 28915.23 Heavy Snowfall Frequencies in Great Britain 1861–1999 28915.23.1 Numbers of Heavy Snowfall Days 29015.23.2 Mean Length (In Days) of Heavy Snowfall Events 29115.24 LWTs and Heavy Snowfalls 29215.24.1 LWT Frequency by Decade 29215.24.2 LWT Frequency by Month and Season 29315.24.3 LWT Frequencies Before, During and After the Heavy Snowfall Day 29315.25 Depressions and Heavy Snowfalls 29315.25.1 Depression Trajectories Associated with Heavy Snowfall Events 29315.25.2 Depression Traffic Associated with Heavy Snowfall Events 29315.26 Fronts Associated with Heavy Snowfall Days (1937–1999) 29615.26.1 Geographical Variations in Meteorological Fronts 29615.26.2 Relationship Between Fronts and LWT 29715.27 Concluding Remarks 297Acknowledgements 298References 298AppendicesAppendix A: Data (Web Material) Appendix B: Selected Pictures from Conferences and Meetings 301Appendix C: Tornadoes in the United Kingdom and Ireland 1054–2013 319Appendix D: Data (Web Material) Selected Name Index 321Subject Index 323