Chicago Mackinac weather set to test big fleet

by Race to Mackinac - event media on 16 Jul 2011 The 103rd Chicago Yacht Club’s Race to Mackinac presented by Veuve Clicquot started this afternoon for the 50 boat cruising fleet. Tomorrow, the massive 310 boat race fleet will head 333 miles north, with the first start for double-handed boats scheduled at 11:30am.

Meteorologist Chris Bedford presented a detailed weather update to a very attentive Skippers' briefing at Chicago Yacht Club’s Monroe Station this morning and again this afternoon.

Earlier this week, the weather picture looked quite straight forward for the sailors but the slow moving high that has delivered such gorgeous weather to the Great Lakes over the last four days has complicated the race for tacticians looking to plot the fastest course. Bedford explained that earlier in the week, it seemed that there could be a well-established southerly flow for most of the race but now lake and land breezes would become much more important.

The tactical decisions have been made more complex, because cool weather over the last few months has meant that the lake temperature is down at least five degrees from a normal year, modifying the thermal wind strengths. A light east south-easterly lake breeze is likely at the start, but it could die quite soon after dark, before changing to a south-easterly gradient breeze overnight. So the positioning of the boat relative to the shore will be a key factor in on water success.

The wind is likely to be strongest along the Wisconsin shore but conditions will vary considerably across the lake. A south-westerly breeze is likely to fill in across the lake late tomorrow but there could be nightly thunderstorms providing regularly challenges.

The cruising fleet started in winds of between 10-12 knots and stayed left on the course.

It is likely that the race leaders will take at least 30 hours to reach the finish line that is well outside the record race times set by the late Steve Fossett (18 hours, 50 minutes) in 1998 with the multihull Stars and Stripes. The late Roy E. Disney set the monohull record (23 hours, 30 minutes) in Pyewacket in 2002.

It does seem that the race leaders will see the strongest conditions as they close on the Mackinac Bridge, which could coincide with a frontal change. But by then it is likely the race will have been won or lost in the difficult mid-race transition stages.

The details from the weather briefing can be found on the home page of www.cycracetomackinac.com