Tide clocks and watches | National Tidal and Sea Level Facility National Tidal and Sea Level Facility Tides Storm surges Products About About tides Tides – questions and answers Sea level – questions and answers The Doodson-Légé Tide Predicting Machine Tide clocks and watches Tidal river bores The River Dee / Afon Dyfrdwy The River Mersey UK National Tide Gauge Network Data availability Tidal predictions – UK and Ireland UK South Atlantic Network Gibraltar sea level station Tidal predictions – South Atlantic Tide gauge instruments Definitions of tidal levels Chart datum and ordnance datum Permanent Service for Mean Sea Level (PSMSL) (external link) Engineers’ page Proudman Building, Liverpool weather station About storm surges Tide-surge model Surge model forecast Surge model archive Surge model archive: 2004–2019 Surge model ensemble forecasting Skew surges Skew surge history: England – south Skew surge history: England – east Skew surge history: England – west Skew surge history: Wales Skew surge history: Scotland Skew surge history: Northern Ireland Skew surge history: Isle of Man Skew surge history: Channel Islands Sea level trends Sea level trend charts Software Tide clocks and watches Tide clocks and watches are practical ways of indicating the state of the tide, in addition to consulting local tide tables. Tide clocks Most tide clocks work by using a 12 hour 25 minute cycle. Generally in the UK and Ireland they vary in accuracy between plus or minus 30 minutes over a 30-day period. Therefore it is necessary to reset them using local tide tables every month or so. Tide watches Some watches with a moon/tide mode require lunitidal intervals so that they can indicate high and low waters. There are two definitions for this interval, which depends on whether adjacent high waters, or the mean of high waters over a lunar month are being considered. High water lunitidal interval The high water lunitidal interval (or high water interval) is the time interval between the moon's transit and the next high water. The interval may be taken from the local time of moon's transit to the local time of high water, or it may be taken from the Greenwich time of the moon's transit to the standard time of high water. Mean lunitidal interval Also referred to as the mean high water interval, this is the mean value of all the high water intervals throughout at least a lunation of 29 days , and this is what is given below. Lunitidal interval The mean lunitidal intervals (mean high water intervals) are calculated using this equation: interval (hours) = phase (degrees) period (hours) 360 (degrees) Use the values from the table to set the moon/tide mode of your watch. These values should be sufficient information for watches that use the lunitidal interval to indicate high and low waters. The following list is ordered by adjacent locations around the coast. Please note : Check your watch against local tide tables to confirm your setting. If your location in the UK or Ireland is not mentioned, try using the nearest one or average between the two nearest places on either side – however, this is not guaranteed to work. The usual disclaimer applies to any information given. Location Latitude Longitude Interval (hr:mn) England – south Avonmouth 51° 30.4′N 2° 43.2′W 6:57 Hinkley Point 51° 13.0′N 3° 7.4′W 6:19 Minehead 51° 12.9′N 3° 28.3′W 6:11 Ilfracombe 51° 12.6′N 4° 6.6′W 5:36 Newquay 50° 25.1′N 5° 5.2′W 4:53 St. Mary’s (Isles of Scilly) 49° 55.0′N 6° 18.7′W 4:31 Newlyn 50° 6.1′N 5° 32.9′W 4:36 Falmouth 50° 9.4′N 5° 4.2′W 5:02 Plymouth (Devonport) 50° 22.9′N 4° 10.8′W 5:19 Torquay 50° 27.5′N 3° 31.7′W 5:51 Portland 50° 35.6′N 2° 26.2′W 6:40 Weymouth 50° 36.4′N 2° 27.0′W 6:36 Bournemouth 50° 42.9′N 1° 52.5′W 9:24 Christchurch (Quay) 50° 43.8′N 1° 46.8′W 10:37 Lymington (Entrance) 50° 45.2′N 1° 31.4′W 11:02 Cowes (Isle of Wight) 50° 46.1′N 1° 17.9′W 11:21 Southampton 50° 53.7′N 1° 24.3′W 11:19 Portsmouth 50° 48.8′N 1° 6.1′W 11:16 Littlehampton 50° 47.9′N 0° 32.5′W 11:08 Shoreham 50° 49.7′N 0° 14.9′W 11:06 Newhaven 50° 46.9′N 0° 3.5′E 11:05 Dungeness 50° 54.8′N 0° 58.7′E 11:14 Dover 51° 7.6′N 1° 20.2′E 11:27 England – east Margate 51° 23.4′N 1° 22.8′E 11:47 Sheerness 51° 26.8′N 0° 45.0′E 12:12 Southend 51° 31.7′N 0° 43.0′E 12:11 Coryton 51° 30.7′N 0° 32.5′E 12:24 Tilbury 51° 27.3′N 0° 20.3′E 0:18 North Woolwich 51° 29.9′N 0° 3.6′E 0:44 London Bridge 51° 30.5′N 0° 5.3′W 1:10 Shivering Sand 51° 29.9′N 1° 4.7′E 11:59 Walton-on-the-Naze 51° 50.7′N 1° 16.5′E 11:25 Harwich 51° 56.8′N 1° 17.1′E 11:18 Mistley Quay (River Stour) 51° 56.7′N 1° 4.8′E 11:30 Felixstowe 51° 57.5′N 1° 20.8′E 11:05 Lowestoft 52° 28.3′N 1° 45.1′E 8:57 Gorleston (Great Yarmouth) 52° 34.3′N 1° 44.3′E 8:17 Cromer 52° 56.1′N 1° 17.7′E 6:30 Hunstanton 52° 56.4′N 0° 29.2′E 6:11 King’s Lynn 52° 45.3′N 0° 23.4′E 6:34 West Stones (River Great Ouse) 52° 49.7′N 0° 21.5′E 6:19 West Lighthouse (River Nene) 52° 48.5′N 0° 12.6′E 6:17 Tabs Head (Rivers Witham/Welland) 52° 56.0′N 0° 5.0′E 6:13 Roaring Middle Light (Wash) 52° 58.6′N 0° 20.9′E 6:04 Gibraltar Point 53° 5.3′N 0° 20.0′E 5:54 Skegness 53° 8.7′N 0° 20.9′E 5:47 Boygrift 53° 17.7′N 0° 19.2′E 5:38 Inner Dowsing Light 53° 19.0′N 0° 35.0′E 5:35 Spurn Point 53° 34.2′N 0° 6.4′E 5:12 Bull Sand Fort 53° 33.7′N 0° 4.1′E 5:16 Immingham 53° 37.9′N 0° 11.2′W 5:35 Hull 53° 44.3′N 0° 19.9′W 5:59 Blacktoft 53° 42.4′N 0° 43.5′W 6:58 Withernsea 53° 43.6′N 0° 2.6′E 4:37 Scarborough 54° 16.9′N 0° 23.4′W 3:49 Whitby 54° 29.6′N 0° 36.8′W 3:35 River Tees (Entrance) 54° 38.9′N 1° 8.9′W 3:18 North Shields (River Tyne) 55° 0.6′N 1° 25.8′W 3:04 Scotland Leith 55° 59.4′N 3° 11.0′W 1:54 Rosyth 56° 1.3′N 3° 26.7′W 1:53 Aberdeen 57° 8.7′N 2° 3.6′W 0:50 Moray Firth 57° 36.0′N 4° 0.4′W 11:37 Cromarty Firth 57° 41.1′N 4° 2.1′W 11:33 Wick 58° 26.5′N 3° 4.9′W 11:07 Lerwick 60° 9.3′N 1° 8.4′W 10:45 Sullom Voe 60° 27.6′N 1° 18.1′W 9:13 Kinlochbervie 58° 27.3′N 5° 2.8′W 7:10 Stornoway 58° 12.3′N 6° 23.3′W 6:49 Ullapool 57° 53.7′N 5° 9.4′W 6:55 Tobermory 56° 37.3′N 6° 3.9′W 5:49 Oban 56° 24.8′N 5° 28.6′W 5:38 Port Ellen (Islay) 55° 37.6′N 6° 11.3′W 3:07 Millport 55° 45.1′N 4° 55.8′W 11:49 Greenock 55° 56.9′N 4° 44.6′W 11:55 Portpatrick 54° 50.4′N 5° 7.2′W 11:27 England – west Workington 54° 39.2′N 3° 34.7′W 11:27 Barrow (Ramsden Dock Entrance) 54° 5.6′N 3° 13.5′W 11:24 Roa Island 54° 4.2′N 3° 10.4′W 11:20 Halfway Shoal 54° 1.4′N 3° 11.9′W 11:11 Heysham 54° 2.0′N 2° 55.5′W 11:14 Fleetwood 53° 55.1′N 3° 0.5′W 11:15 Liverpool (Gladstone Lock) 53° 27.0′N 3° 1.1′W 11:04 Liverpool (Princes Pier) 53° 24.4′N 3° 0.0′W 11:09 Birkenhead (Alfred Lock) 53° 24.3′N 3° 0.9′W 11:09 Eastham 53° 19.5′N 2° 57.0′W 11:22 Hilbre Island 53° 23.1′N 3° 13.8′W 10:57 Wales Llandudno 53° 19.9′N 3° 49.5′W 10:41 Holyhead 53° 19.4′N 4° 37.6′W 10:04 Barmouth 52° 43.1′N 4° 2.9′W 8:14 Aberystwyth 52° 24.4′N 4° 5.5′W 7:55 Fishguard 52° 0.2′N 4° 58.6′W 7:09 Milford Haven 51° 42.2′N 5° 3.2′W 5:58 Mumbles 51° 34.2′N 3° 58.4′W 5:57 Swansea 51° 36.5′N 3° 55.7′W 5:57 Newport 51° 32.7′N 2° 59.2′W 6:44 Northern Ireland Bangor (County Down) 54° 40.0′N 5° 40.3′W 10:57 Belfast 54° 36.1′N 5° 55.2′W 10:54 Larne 54° 50.9′N 5° 47.8′W 10:55 Portrush 55° 12.3′N 6° 39.6′W 6:47 Coleraine (River Bann Entrance) 55° 10.2′N 6° 46.4′W 6:50 Londonderry 54° 59.5′N 7° 19.0′W 8:10 Ireland Malin Head 55° 19.8′N 7° 22.4′W 6:07 Galway 53° 16.1′N 9° 2.9′W 4:50 Tarbert Island (River Shannon) 52° 35.2′N 9° 21.5′W 5:17 Cork (City) 51° 54.0′N 8° 27.3′W 4:15 Cobh 51° 51.0′N 8° 17.8′W 5:09 Ringaskiddy 51° 49.9′N 8° 19.4′W 5:15 Barrow Bridge 52° 16.8′N 7° 0.2′W 5:25 Rosslare Harbour 52° 15.4′N 6° 20.3′W 5:25 Dublin (North Wall) 53° 20.8′N 6° 13.5′W 11:16 Isle of Man Douglas 54° 8.9′N 4° 28.0′W 11:16 Port Erin 54° 5.1′N 4° 46.3′W 11:05 Channel Islands St. Helier 49° 10.5′N 2° 7.0′W 6:18