Snowflakes in the forecast? More than once?

Be patient: there's also a warm-up!


DETROIT – Before getting to the forecast, just a quick word about this morning:

The band of rain approached our area right on schedule, temperatures were near to below freezing, and dewpoint temperatures (an indication of moisture in the air) were in the mid 20s. It's important to remember a very important law of meteorology: the dewpoint temperature cannot fall below the air temperature. The temperature / dewpoint setting this morning suggested that, as the rain moved in, temperatures would initially drop into the upper 20s before rising above freezing.

However, dewpoints rose very, very quickly. For example, the dewpoint at my house at 6 a.m. was 24°, and it rose all the way to 29° by 7:45 a.m. -- amazing. As a result, temps hardly dropped at all when the rain began, and some of us only had a very brief period of freezing rain before temps rose above freezing.

All-in-all, I don't think anybody's going to complain given that the rain moved in during the morning rush hour. But I wanted to share this to help you appreciate some of the thermodynamics I have to predict in order to forecast your weather -- there's a lot that goes into making a forecast in situations like this.

Follow me on Twitter: @PGLocal4

Tonight brings another thermodynamics test for me. Right now, I think we'll see some rain showers move into the area late at night and perhaps mix with some wet snowflakes. Lows will drop into the mid 30s, so I don't expect any freezing on paved surfaces.

Thursday's sunrise is at 7:27 AM, and Thursday's sunset is at 7:52 PM.

On Thursday, some computer models suggest a change from rain showers to snow showers, but whatever precipitation we get should end by late morning, and the best chance to see precipitation will be south of 8 Mile. Highs will reach the low to mid 40s, so the above freezing temperatures mean that roads will just be wet. With a little luck, perhaps we'll see some sun by the end of the afternoon. Northwest wind at 10 to 15 mph.

Partly cloudy Thursday night, with lows in the low to mid 20s.

An approaching cold front on Friday will generate some light snow showers, with those of you near Lake Huron possibly seeing a bit more robust batch of snow showers. Highs in the low 30s.

Gradual clearing Friday night, with lows in the mid teens.

Mostly sunny on Saturday, with highs in the mid 30s.

Mostly clear Saturday night, with lows in the low 20s.

Increasing clouds and becoming windy on Sunday with a chance of rain or snow showers. Highs in the mid 40s.

Rain and/or snow showers end Sunday night, with lows in the mid 30s.

Partly cloudy Monday, with highs in the mid 40s.

Partly cloudy Monday night, with lows in the upper 20s.

Partly cloudy on Tuesday, with highs near 50.

Partly cloudy Tuesday night, with lows in the mid 30s.

Then partly cloudy on Wednesday, with highs in the upper 50s.

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