For Lake Erie, I add the 2 wind speeds that are on the news together for a more real guess of how rough the lake is or will be. 15mph total would be a reason to not go unless the walleye are in a stage where they are closer to shore. 15mph winds and my wife won't go more than a 4 mile run. I fished tournaments for 20+ yrs. They send you out in anything 6ft or less. Sometimes with over 40 mile runs one direction. Not fun, but learned what I could/could not due.
If you buy a Mi fishing lic. Like mentioned allows you to fish the Mi shoreline/waters in a west wind. Also except for a 20mph south wind. The Detroit river is available.
Keep in mind. In spring (only) the water is cold. The wind is warm. The warm air skips up/ over the very cold water. Once the water starts to warm up, 50* or so. This stops happening.
So an offshore (south) wind in Oh at 20mph doesn't create much wave actions for 3 to 4 miles out before getting rough. Same when there is a strong west wind on the Mi side, calm waters for around 4 miles out. And the fish are closer in at this time.
Any questions, PM me.