WEST MICHIGAN — A weak cold front will quickly make its way through the Great Lakes region this afternoon, with less humid air coming in behind it. Dew points as of this writing — a direct measure of how much moisture is in the air — are still in the 60s across most of West Michigan:
As this front passes (and I think it will happen sometime between 2 and 4pm), there could be an isolated shower or storm east of US-131, but most of us will stay rain-free. The main changes this front will bring will be lower humidity and more comfortable temperatures at night with lows dropping into the upper 50s tonight and tomorrow night.
In the meantime, a lot of people are probably anxious to go boating, fishing, and maybe even swimming on Lake Michigan. Water temperatures near the shoreline were generally in the 60s as of Friday, which is considered “tolerable” for a quick dip for most Michiganders. However, these water temperatures have dropped off significantly in the past 36 hours:
Water temperatures, as you can see, are now in the upper 50s to near 60°. This is a little to chilly for most people to try to jump in. I think the reason these water temperatures have dropped off has to do with the south to southeast winds we had Friday night into Saturday morning. This wind has an offshore component to it, which blows the surface water out into the middle of the lake and forces colder water from the depths of the lake to replace it.
With winds expected to become more southwesterly and westerly this afternoon and tonight, the warmer surface water will likely move back in. This, along with continued warmer than average air temperatures for this time of year, should allow the near shore waters to warm back up into the 60s by Memorial Day.