Forecast: A possible rain drop this weekend in metro Detroit?

Will we be able to see the Super Moon eclipse?


DETROIT – Before getting to the forecast, just a quick word about fog, since some of you have started a few days this week with dense fog, while others haven't seen much of anything.

Fog is basically a cloud at the ground. Air can "hold" a certain amount of water vapor, based upon its temperature. As the air cools, it can hold less and less water vapor. When temperatures fall to such a point that the air is completely saturated with water vapor (100 percent humidity), that temperature reached is called the dewpoint temperature -- and the air temperature cannot ever fall below the dewpoint. If the air continues cooling, the air parcel must shed some of its water vapor in order for the dewpoint to also drop -- and those little droplets of water floating in the air are what we see as fog (or clouds up in the sky).

So, you can now see that, the closer together the temperature and dewpoint are, the more humid the air is. During this past week, east and northeast winds brought Lake Huron, Lake St. Clair, and Lake Erie moisture inland -- to some of us. Those who got that moisture saw dewpoint temps rise, which made it much easier for fog to develop since the air didn't have to cool as much to saturate. Those who didn't get that moisture, had relatively lower dewpoints, and the temp had to fall much farther to get fog. I hope that "clears the air" for you about this week's fog!

Alright, here's your forecast:

Partly cloudy to mostly clear overnight, with patchy fog possible later at night. Lows in the upper 50s (that's 15° Celsius for our Canadian neighbors). Northeast wind at 3 to 6 mph.

Mostly sunny on Saturday -- a great day for college football, a round of golf, some tennis, your dog taking you for a walk, and the Cider Mill. Highs in the mid 70s (24° Celsius). East wind at 8 to 13 mph.

Saturday's sunrise is at 7:25 AM, and Saturday's sunset is at 7:24 PM -- almost exactly twelve hours of daylight and nighttime, which is to be expected given that the autumnal equinox (first day of fall) occurred this week.

Increasing clouds Saturday night, with lows in the upper 50s.

Sunday forecast:

Mostly cloudy on Sunday, with the very slight chance for a few brief, light showers -- many of us will probably end up with a dry day. Highs in the low 70s.

Mostly cloudy Sunday night, with lows near 60. Right now, conditions don't appear favorable to see the Super Moon eclipse Sunday evening.

But, just in case the clouds do break, here's what you need to know:

This eclipse is a special one because it coincides with this year's "Super Moon" (the full moon that's closest to the Earth for the calendar year). The last "Super Moon Eclipse" was in 1982, and the next one won't be until 2033. Partial eclipse begins at 8:07 PM, totality (when the moon takes on a reddish color…that's why it's also called a "Blood Moon") is from 10:11 to 11:23 PM, and the eclipse ends by 12:27 AM. Remember that lunar eclipses are perfectly safe to look at, and you don't need a telescope! By the way, this is the last lunar eclipse of any kind until January 2018.

Becoming partly cloudy on Monday, with highs back into the mid 70s.

Partly cloudy Monday night, with lows in the low 60s.

Finally, a cold front approaches at some point on Tuesday, with a band of light showers with it. Highs in the low to mid 70s, depending upon the front's timing.

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