By Wally Cross
The summer is heating up and so is the water and land. It is time to consider all the options when deciding on your course or route.
Sailing software like Expedition and Deckman provide clues on the best routes based on a combination of your boat's performance (VPPs) and the predicted weather. This information is a good clue but not hard fast. In the past we would pay for weather, thinking it would provide secrets to this race, yet in reality it was no more valuable than the information you can get online.
Get Information First
- Make sure you can get internet service the entire race.
- Download Yellow Brick and view every four hours.
- Look at weather one week in advance in all locations on the lake.
Look at weather early for possible clues on how the wind direction and speed change based on the time of day. Cold water and warm land will affect the direction and wind speed along the shore. The map is in the morning with a south wind direction.
This map is from 2:00 pm mid-day after the land warms up. Both shores are producing a thermal wind direction. Each shore line would have more wind speed with an east wind on the US shore and a west wind on the Canadian shore.
This map is at 1:00 am after the land cools. The land breeze or night thermal is only on one shore. This new wind direction is affected by the land temperature relative to the water and the direction of the upper gradient wind direction.
Weather information from various buoys on Lake Huron is available on the Great Lake's page of NOAA's National Weather Service website. Access this information during the race for clues about what's coming.
Bookmark all your online weather sites for easy access. Every four hours, check to see if the weather is following the pattern from the last forecast. Check out Yellow Brick to monitor your progress relative to your competitors.
A good strategy is to think of the race in quarters, evaluating the weather and planning individually for each period of time.
Quarter One is during the first day with a combination of sun, cold water and warm land. Usually there is some land influence during this period. Look for clouds along the shore to determine if there is a thermal; if so there will be more wind closer to shore.
Quarter Two is the first evening. The shore boats need to make a decision on how far offshore to sail while boats on the Cove Island course need to determine how far west or east of rhumb to sail. The shore course boats need to assess whether the gradient wind will line up with a land breeze off the shore. The Cove Island boats will decide if the new wind from the west is better than sailing in the old wind that will travel east. General rule of thumb is to race for more pressure.
Quarter Three is the first morning and mid-day. The land will be cool so it is all about finding the gradient wind. This period is also a good time to set up for the afternoon thermals along the shore course. Cove Island boats now are deciding whether to sail more south if the wind is more from south or east, or a northern route if the wind is more from the west or north.
Final Quarter is the finish area. Based on the timing, all of the land around Mackinac Island can influence not only the wind speed, but also direction. If arriving during the day, the shore lines are good; at night mid-water seems safer.
- Determine if the wind is a gradient wind direction or a land thermal breeze.
- Make a decision about the breeze of the first evening based on wind direction aloft and the day's thermal breeze.
- Use all your clues from the buoys to the north, the weather to the south, and your current conditions relative to early predictions.
Sailing the Circle Fast
- Draw a circle up the course every 60 miles with a 5-mile diameter on rhumb line.
- Based on your current wind direction, decide what course will allow you to enter the circle first.
- This system will allow you to climb the north ladder faster than just sailing a rhumb line course.
Note: Have questions on circle sailing? Give me a call at 586-776-1330.
Rules of the Road
- Research weather one week in advance.
- Understand your boat's polar speed and angles.
- Visualize now at home how you would sail the race in current conditions.
- Make a plan Friday night and then again Saturday morning.
- Base your start on your first quarter plan.
- Check your results visually early on, and later with Yellow Brick.
- Sail fast all the time….5% faster than target speeds.
- Make course decisions based on your boat's best course.
- Use circles to keep you from sailing too far off course.
- Win by sailing fast/smart yet within the circle.
Quantum's Wally Cross is a 45-year veteran of the Bayview Mac Race. Over the coming weeks, Cross will provide information and tips to help teams prepare for a rewarding and enjoyable experience. Wally is available for in-person or phone consultations with interested boat owners. To review your program or for more information, contact Wally at firstname.lastname@example.org or 586-776-1330.