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Tide predictions 1066 Tidal York The tidal river Ouse
These figures were very kindly computed by the Hydrographer to the Royal Navy whose help is acknowledged and very much appreciated.
These are the raw figures for Goole, which is the nearest place to the mouth of the Ouse
53°42'N, 0°52'W England 19 - 25 September 1066
ALL TIMES IN GMT ; ALL HEIGHTS IN METRES ABOVE CHART DATUM
19/9/1066
High 11:05 4.5 m
High 23:39 4.2 m
Low 06:44 0.2 m
Low 18:58 0.3 m
20/9/1066
High 12:01 3.9 m
Low 07:26 0.3 m
Low 19:29 0.5 m
21/9/1066
High 00:36 3.8 m
High 13:09 3.5 m
Low 08:18 0.5 m
Low 20:04 0.6 m
22/9/1066
High 01:42 3.6 m
High 14:32 3.3 m
Low 09:27 0.5 m
Low 22:03 0.8 m
23/9/1066
High 02:52 3.5 m
High 15:51 3.5 m
Low 10:41 0.5 m
Low 23:26 0.6 m
24/9/1066
High 03:59 3.8 m
High 16:49 4.0 m
Low 11:56 0.3 m
25/9/1066 (19/9/1066 on pre-Gregorian calendar)
High 04:58 4.2 m
High 17:37 4.5 m
Low 00:34 0.4 m
Low 13:08 0.1 m
Some notes
 | We lost 10 days in 1582, however the calendars were coincident in 325 AD and hence the difference varies from 10 to 0 days over that period. |
| Therefore, in 1066 the difference was only 6 days, and so 19 September 1066 in the Julian calendar became 25 September 1066 in the Gregorian calendar. |
| No account has been taken of any meteorological effects. The effects of wind, its direction and pressure can alter the observed tide from the predicted values. |
| Changes in the topography and landscape could also have radical effects on the tides. |
| At Goole the amount of fresh water coming down the rivers has little effect on the heights of high water. The levels for low water are given for a low rate of river flow caused by run-off from the catchment area. High rates of river flow can increase the level of low water by as much as 0.6 m. |