UPDATE: See photos of another round of big waves battering Michigan's shores
Lake Michigan waves neared record territory Friday as gale-force winds churned the waters into massive breakers on shorelines across the state.
The southern buoy, located in the middle of the lake due west of Holland, recorded a 21.7-foot wave height earlier this afternoon. That mark ties for the second tallest height ever recorded for that buoy, according to the National Weather Service in Chicago.
It, too, measured a wind speed of 59 mph, just below its all-time highest speed at 62 mph set on Nov. 10, 1998.
More: 'Stay off piers': 15-foot waves could batter Lake Michigan shoreline as potent storm approaches
And for another interesting fact, the buoy reports the water temperature is about 7 degrees warmer than the actual air temperature.
Although Michigan's Upper Peninsula saw accumulating snowfall during much of the day, and a few flakes piled up elsewhere, winds have been the greatest nuisance across the Great Lakes region. A wind advisory remains in effect for the southern half of the state through 7 p.m. Friday at the earliest.
Grand Rapids and Ionia reported a peak wind gust by 4 p.m., with Saginaw just a tick higher. Gusts are expected to lessen through the prime trick-or-treating hours.
The highest wave recorded by the south buoy: 23 feet. It came in September 2011. The buoy has been measuring waves since 1981.
Andrew Krietz covers breaking, politics and transportation news for MLive and The Grand Rapids Press. Email him at akrietz@mlive.com or follow him on Twitter.