So  far, the models have been correct with the timing (starting about 8 AM) and the precipitation type (snow).   I was beginning to be concerned about the accuracy of the forecast when I woke up and the outdoor temperature was 34 degrees.

But once the precipitation started, temperatures dropped to 31.

The 2AM run of the NAM has the QPF almost 0.80 inches, but much of the heavier precipitation will fall in the afternoon, according to the NAM.   This most recent NAM run has the temperatures at 6000ft (800 mb) moving above freezing during the later half of the afternoon,  allowing the snow to mix or change to rain or a mix…..so another parameter has shifted towards decreasing snow totals.

The grassy surface vs road accumulation difference is already apparent.   Getting the final accumulations numbers correct with this storm is probably both meaningless and impossible.  I think you get the idea.

I’ll update when the next NAM FOUS data becomes available about 10:45 AM.

Latest GFS model data in. Here is the trend. QPF values remain about the same at 0.65 inches water, and it has the precip  heavy both  in the morning and afternoon.  Looks to be all snow.

Looking at the GFS and again at the at the NAM  FOUS data, the temperature profile is trending colder.

A tough call-

I’m going back to my original forecast:  4, possibly 5 inches of snow on grassy surfaces in the immediate suburbs, less in the city. Less on roadways. Up to 6 inches in far northwestern suburbs. Precip ends about 10  pm

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Latest NAM model data in.  Here is the trend.   QPF values remain about the same at 0.67 inches water, but the heaviest preciptation has shifted to the afternoon and lingers later into the evening.

With the heaviest precip occuring during the warmer afternoon hours, somewhat lower snow totals in the city and the the immediate suburbs.  Two, possibly four inches of snow on grassy surfaces in the immediate suburbs, less in the city.  Less on roadways.   Up to 6 inches in far northwestern suburbs.  Some mixing with rain possible late afternoon.  Precip ends about 9 pm

This snow will look worse from your window than it will really be.   A messy day, weatherwise.