OVERVIEW



Use the North West Passage to arrive in an area about 250 metres south of 'Steeple Rock' west cardinal marker buoy, Q(9)15s. It is moored about 350 metres southwest of the rock and serves to mark both the entrance to the North West Passage and this cut between the islands. As always, beware of lobster pot buoys in and around Scilly.



From the 'Steeple Rock' waypoint steer the course bearing 058°T (reciprocal 238°T) east by northeast towards the passage which should be visible between Mincarlo Island and Bryher, passed to port, and Samson, passed to starboard, searching out the transit.



The first mark is Yellow Rock which is a small rocky islet, 3.9 metres high, a little over two miles distant laying between Samson and Bryher.



Once this is identified look for the Abbey Hill monument situated ¾ of a mile to the northeast of Yellow Rock on Tresco. Once identified bring the monument over Yellow Rock to provides a range mark that tracks into the second 'Bream Ledge' waypoint. Keep on transit as dangers lie close to the track on both sides.

Depart the alignment after 'Beam Ledge' waypoint as the alignment soon after passes unnecessarily close to Long Ledge, that extends from Sampson, and over an isolated shoal that dries to 1.2 metres located a little over ½ a mile along the shoal.

The 'Clovel' waypoint sets up a course to pass between the Outer Clovel Rocks and the aforementioned shoal with a further outer and covered shoal with 0.9 metres LAT over it.




From here the course continues in between Bryher and Yellow Rock into the Tresco Channel. The final waypoint is close before it dries at LAT, 150 metres south by southeastward of the isolated Lubber's Rock, that dries to 1.7 metres, on Bryher side of the channel and opposite from Appletree Point.

From here, with a sufficient rise of the tide proceed to New Grimsby Sound by steering northeastward to connect to the track of the Tresco Channel crossing the Tresco Flats .




The harbour master has placed two white posts in Cliff Field, beneath Plum Hill on the Tresco shore, that provides a transit northwest side of the sand spit clearing Lubber's Rock and the rocks from Appletree Point. It will also keep clear of Little Crab Ledge, that dries to 2.4 metres, and Great Crab Ledge, that dries to 5.3 metres.




This may be used to converge with the track of the Tresco Channel crossing the Tresco Flats to continue into New Grimsby Sound.




LISTED WAYPOINTS
The complete course is 2.48 miles from the waypoint 'Steeple Rock' to 'Lubber's Rock' tending in a north easterly direction (reciprocal south westerly).

What is the best sailing time?

May to September is the traditional UK Sailing season with June-July offering the best weather. The British Isles weather is highly variable, and the amount of bad weather varies quite widely from year to year. This is because they are islands positioned between the Atlantic Ocean and the large landmass of continental Europe. As a result, the entire area lays under an area where five main air masses meet and alternate:

• • Tropical Maritime Air Mass - from the Atlantic


• • Polar Maritime Air Mass - from Greenland


• • Arctic Maritime Air Mass


• • Polar Continental Air Mass - from central Europe


• • Tropical Continental Air Mass - from North Africa

Depending on the movements of the jet stream, any and all of these air masses can come in over the isles, creating weather fronts where they meet and bringing with them all types of weather.

The prevailing winds for the British Isles as a whole are from the western quarter which generally blows for two-thirds of the year predominantly from the southwest. Gales from the westward are felt in all seasons, but from November to March, inclusive, they are most frequent and generally last three or four days. Of these, a southwest gale is considered to be the most powerful system. The winter period is largely characterised by wind and rain.

The fine summer weather of the sailing season is typically punctuated by the passage of an Atlantic depression that bringing periods of strong wind and rain, and sometimes poor visibility. These gales rarely cause surprises as they are usually forecasted well in advance. Good weather windows of 48 hours are easy to predict but any longer than that there's an increasing chance of change.

Fogs are frequent in all parts of the Channel and are formed both on the English and French coasts. In summer they only obscure the land in the morning and are readily dispersed by heat or a light breeze. But the moist haze, driven in by westerly winds from the sea, tends to linger and is only dispersed by strong winds. In the eastern part of the Channel, it is rare for the land to be completely free from mists. The only exception is when the wind is from the northeast which makes the mist free coastline highly distinctive from a great distance.

With thanks to:

Micheal Harpur eOceanic.