Met. 0. 853 METEOROLOGICAL OFFICE British Rainfall 1967 THE ONE HUNDRED AND SEVENTH ANNUAL VOLUME LONDON: HER MAJESTY'S STATIONERY OFFICE: 1973 U.D.C. 551.506.1 © Crown Copyright 1973 HER MAJESTY'S STATIONERY OFFICE Government Bookshops 49 High Holborn, London WC1V 6HB 13a Castle Street, Edinburgh EH2 3AR 109 St Mary Street, Cardiff CF1 1JW Brazennose Street, Manchester M60 8AS 50 Fairfax Street, Bristol BS1 3DE 258 Broad Street, Birmingham Bl 2HE 80 Chichester Street, Belfast BT1 4JY Government publications are also available through booksellers SBN 11 400250 9* Printed in England for Her Majesty's Stationery Office by Manor Farm Press, Alperton, Wembley, Middlesex Dd 507005 K7 5/73 Contents Page Introduction 1 Part I General table of rainfall Index to areal grouping of rainfall stations 5 General table of rainfall monthly and annual totals with amounts and dates of maximum daily falls 7 Part II Summary tables, maps and graphs with discussion 1 Main characteristics of the year 99 2 Monthly, annual and seasonal rainfall 101 3 Spells of rainfall deficiency and excess 123 4 Frequency distribution of daily amounts of rain 137 5 Heavy falls on rainfall days 152 6 Heavy falls in short periods 169 7 Evaporation and percolation 175 8 Potential evapotranspiration 180 Part III Special articles 1 Potential evapotranspiration data, 1967, by F. H. W. Green 184 2 Snow survey of Great Britain, season 1966-67, by R. E. Booth 191 3 Estimates and measurements of potential evaporation and evapotranspiration for operational hydrology, by B. G. Wales-Smith 203 111 LISTS OF MAPS AND GRAPHS PARTS I AND II Page Parti Areal grouping of rainfall stations 4 Part II Monthly rainfall, percentage of annual average, January to December (12 maps) 105 Seasonal rainfall, percentage of annual average, Winter half-year (October 1966-March 1967) 117 Summer half-year (April 1967-September 1967) 118 Seasonal year (October 1966-September 1967) 119 Rainfall 1967, percentage of annual average 120 Rainfall 1967, millimetres with inch equivalents 121 Percentage departures of cumulative rainfall: map showing distrib­ ution of stations included in Table 3A and graphs 125 Graphs illustrating spells of rainfall deficiency and excess (19 stations) 129 Number of rainfall days with 1-0 mm or more, 2-5 mm or more, and 10-0 mm or more, seasonal half-years and calendar year (9 maps) 143 Rainfall of 27 February: northern England, Wales to south-west England 160 24 March: central and western Scotland 161 3 May: Wales and south-west England 162 14 May: Midlands and northern England 163 24 June: Shropshire to Tees-side 164 13 July: north-west England, Wales to Oxfordshire 165 22 July: south-west and southern England 166 29 July: south Wales 166 16 October: England and Wales and Isle of Man 167 5 November: north-east England 168 LIST OF TABLES, PART II Table 1 Estimated areal rainfall, monthly, annual and seasonal, for parts of the United Kingdom A Averages 1916-50 in millimetres 100 B Values for 1967 in millimetres 100 C Values for 1967, percentage of annual average. 1916-50 100 2 Monthly, annual and seasonal rainfall for individual stations, percentage of ann ual average, 1916-50 101 3A Percentage departures of cumulative rainfall 126 3B The calendar year divided into 73 five-day groups, or pentads 128 4 Frequency distributions of daily amounts 138 5 Chronicle of heavy falls on rainfall days 153 6 A Frequency distributions of intense falls 170 6B Heavy falls in short periods 173 6C Heavy falls in short periods. Supplementary list 174 7A Evaporation from standard tanks 176 7B Rainfall, percolation and inferred evaporation 178 7C Rainfall, drainage observations and inferred evaporation 179 8 Calculated potential evapotranspiration 181 IV Introduction No important changes in the presentation of data over the areas draining down to the R.F.M. stations have been introduced with this volume of British are given. Rainfall. However, all data are published in metric units for the first time, including those in special In order to publish as much useful data as possible, articles in Part III, individual authors having kindly marginally incomplete records have been completed provided metric versions of their articles in place of by estimation of the missing data. Values estimated the versions prepared with British units some years for missing data for England and Wales are included earlier. in brackets. Because of certain complexities in the change from manual methods to computer methods As in all the volumes since the 1961 edition, the river of producing the General Table and other tabular flow measurement stations are included in their material, this practice of using brackets for estimated appropriate places in the General Table and are values was not thoroughly carried out for Scotland indicated by the abbreviation 'R.F.M.Sta.'. Where and Northern Ireland in the present volume nor in the available, the 1916-50 average annual areal rainfalls volume for 1966. BRITISH RAINFALL 1967 Part I General table of rainfall AREAL GROUPING OF RAINFALL STATIONS based on drainage areas See page opposite for index KILOMETRES 0 20 40 80 80 100 120 140 160 L MM 0 *»1«/t«i/l44|4Llllll 4 INDEX TO AREAL GROUPING OF RAINFALL STATIONS Hydro- Hydro- metric metric Area area Page Area area Page England and Wales Scotland River authority area River purification board area Northumbrian 22-25 7 Solway 77-81 70 Yorkshire Ouse and Hull 26,27 9 Ayrshire 82,83 71 Trent 28 15 Clyde 84-87 72 Lincolnshire 29, 30 20 Welland and Nene 31,32 21 Hydrometric area grouping Great Ouse 33 23 Kin tyre and south-western islands 104 75 East Suffolk and Norfolk 34,35 25 Add, Awe and Etive 88, 89 75 Essex 36, 37 27 Lochy and Linnhe 90, 91 76 Shiel, Alsh and Maree 92-94 77 Inner and Outer Hebrides 77 Conservancy area or London 105, 106 area Laxford 95 78 Lee 38 29 78 London, left Naver and Thurso 96, 97 bank 39 30 Orkney and Shetland Islands 107, 108 78 Thames 39 31 79 London, right bank Wick Water to Conon 1-4 39 35 Beauly and Ness 5, 6 80 River authority area River purification board area Kent 40 36 Banff, Moray and Nairn 7-9 81 Sussex 41 39 Dee and Don 10-12 82 Hampshire 42 41 North and South Esk 13 83 Isle of Wight 101 42 Tay 14-16 83 Avon and Dorset 43,44 42 Forth 17, 18 85 Devon, south 45,46 43 Lothians 19,20 87 Cornwall 47-49 45 Tweed 21 88 Devon, north 50, 51D 47 Northern Ireland Somerset 51S, 52 48 Bristol Avon 53 49 Drainage area grouping Severn 54 50 Foyle and north-western streams 91 Wye 55 54 Lough Foyle, east 91 Usk 56 56 Bann and Lough Neagh 92 Glamorgan 57,58 57 Bush and north-eastern streams 93 South West Wales 59-63 58 Lagan and eastern streams 93 Gwynedd 64-66G, 102 59 Newry and south-eastern streams 94 Dee and Clwyd 66D, 67 60 Erne and western streams 94 Mersey and Weaver 68,69 62 Channel Islands Lancashire 70-74L 65 Alderney 95 Cumberland 74C-76 67 Guernsey 95 Sark 95 Isle of Man 103 69 Jersey 95 Notes: Part of hydrometric area 21 (Tweed) and part of hydro- burn, Etal R.F.M. station and Berwick-on-Tweed under area metric area 77 (Esk) are in England but stations within these 21 (Tweed), and Ashycroft and Longtown under area 77 (Esk). parts are listed with appropriate stations in Scotland so as to be The National Grid reference system is used for locating rainfall grouped within the natural drainage areas to which they belong. stations in Great Britain, the Irish Grid for stations in Northern These stations are Linhope, Lilburn Tower, Chillingham Barns, Ireland, and the Universal Transverse Mercator (Zone 30U) for Middleton Hall, Mindrum, Goldscleugh, Hethpool, Pallins- stations in the Channel Islands. GENERAL TABLE, ENGLAND AND WALES Av. Highest recorded Grid Alti­ 1916- Rainfall in millimetres fall in a day Station reference tude 1950 m mm Jan Feb Mar ( Apr May Jun Jul Aug Sep Oct Nov Dec Year mm date England and Wales NORTHUMBRIAN RIVER AUTHORITY AREA, 9211 SQUARE KILOMETRES HYDROMETRIC AREAS 22(including Till) TO 25 Coastal Newlands ... ... ... NU46 116324 58 657 28 57 26 24 131 40 64 54 55 77 131 47 733 50 5 Nov Seahouses... ... ... NU46 197341 11 35 57 37 25 134 37 70 55 44 74 111 40 718 52 5 Nov Newton House NU 46 235253 23 690 36 57 33 20 124 37 77 52 47 74 117 38 713 56 5 Nov Stamford ... ... ... NU46 223193 53 706 35 65 30 22 129 45 77 61 47 76 129 46 762 52 5 Nov HowickHall ... ... NU 46 246177 34 751 38 56 35 19 129 48 84 65 57 80 119 43 772 43 5 Nov Aln Callaly Castle ... ... NU46 051099 104 812 53 73 38 37 144 56 75 74 69 101 125 56 901 44 5 Nov Whittingham ... ... NU 46 0691 17 76 762 43 62 34 33 136 56 59 61 61 103 123 49 817 43 5 Nov Coquet Blindburn ... ... ... NT 36 829109 307 1002 75 102 61 68 144 54 93 72 77 159 166 62 1132 72 5 Nov Bygate R.F.M. Sta. Area 59.6 km1 ... NT 36 870083 213 1053 I/sway (Coquet) Shillmoor R.F.M. Sta. Area 21.4 km1 ... NT 36 886077 207 1103 Coquet Rothbury ... ... ... NU46 055013 91 877 52 68 42 38 110 46 80 79 75 115 123 51 878 58 16 Oct Amble ..