Round the Island weather

Thermal enhancement, but no seabreeze. Libby makes her call.

The promising forecast of 10-14 knots from the west for the 72nd Round the Island looks set to have blown through on Friday. This leaves the Solent with a lovely day for sunbathing waterskiing and partying but not a promising start for the racing.

A high pressure system is pushing north across today (Friday) and will dominate Saturday’s conditions. The weak occluded front that will stretch across the country will disperse overnight leaving Saturday morning with clear skies and light winds.

The high pressure centre will be located just to the east of the Solent and will gently move eastwards across the day. This will provide light winds from an east southeast direction between 5-8 knots at around 0700 BST. Providing enough wind for the days racing to get underway.

The high pressure system will gradually move to the east and the pressure rise. Midday will see the least wind of the day with the synoptic strength dropping to less than 5 knots while the direction will veer slowly to the south. This is also the time of day when a thermal enhancement may try to take effect.



A sea breeze will not occur as there will be no offshore gradient wind to generate the sea breeze cell. But as the land heats up (with temperatures expected to reach 23˚C) a thermal enhancement will be expected to increase the wind strength by 2-3 knots. This will mean that there will most likely be a short period of lighter winds around midday before the thermal enhancement increases the wind strength to around 6-8 knots again.

Across the afternoon the synoptic wind at surface level is expected to increase to 10 knots combined with the thermal enhancement a wind strength of between 8-12 knots from the south can be expected. After 1600 BST the land will begin to cool and the thermal effect will decrease hence the wind strength will gradually decrease.

For synoptic charts for the weekend check out: www.westwind.ch/?page=ukmb

You may also want to have a look at these two sites, which give you live data
www.chimet.co.uk/default.shtm for wind in Hayling Bay
www.weatherstations.co.uk/links.htm for independent weather stations for current weather readings.