STRONG TIDAL STREAMS

HARBOUR ENTRANCE
Mariners are warned that the entrance to Cowes Harbour is an area of strong tidal flow. The flood (east going) runs from low water (Cowes) to approximately 2.5 hours before high water, when the tidal flow slackens before changing to the west going ebb flow. Maximum rates occur on the ebb tide 
approximately 1.5 hours after HW (Cowes) and can be in excess of 3 knots on spring tides. Close inshore a west going stream running parallel to the east going flood tide may be experienced in the vicinity of No 1 buoy (50 46.07N 01 18.03W approx). Caution should be exercised when approaching the entrance as the tidal flow may change from east to west setting within a few metres particularly in the 2 hours before high water (Cowes). 

INNER FAIRWAY
When the tidal flow at Numbers 1 and 2 fairway buoys is running in a westerly direction, (expected from HW -2hrs to HW +3hrs) a tidal shadow with significantly reduced flow may be experienced immediately west and south of the detached breakwater in the Inner Fairway.
Between HW-3hrs and HW vessels transiting the Inner Fairway between 2A buoy and South Cardinal EC11 may experience a westerly setting cross current of up to 1.5knots which will have a tendency to set vessels down towards the western shore. This cross current splits into two separate flows on the western side of the fairway in between the Island Sailing Club and the Town Quay ferry terminal with a current of up to 1.5knots running along the foreshore in either direction. Small craft should be prepared to alter their heading so as not to be set across the fairway when transiting this area and avoid impeding the safe passage of commercial shipping and ferries.

FAIRWAY
The speed limit is 6 knots through the water.