Update Thu 08:01 AM —We are moving into the range of the higher resolution models during the day today and by this evening’s model runs, things should clarify further.

Based on last night’s GFS, GEFS, NAM SREF, CMC and ECMWF, here are the forecast  trends:

Snow starts 10AM -12 noon.  Some models are leaning towards a later start.  (The high resolution NAM-NEST ( just coming into forecast range)  has a 10 AM start from west to east, but even has some flurries before then.

The current trend for most of the models is less snow accumulation and more of a mix.  The GFS is still in the 1.5 inch range, but the Canadian and ECMWF are closer to an inch or less.   Precipitation ends about 8 PM.

Over the past year, the new National Blend of Models (NBM) has done very well at smartly blending these differences. Here’s the latest NBM  (new version) snow total for 7 PM Saturday evening –

I’ll be updating this evening with the latest models, including the shorter range high resolution models.  Stay tuned.

Update Wed 07:41 PM — Today’s models don’t show any significant changes with the forecast.  However, the timeframe (84 hours) of the storm now falls into the range of the NAM and SREF models.  With these higher resolution models, we have the following trends:

Snow starts perhaps a bit later, about 11 AM.  Heavier precip starts early afternoon.  A changeover or mix with sleet starts as early as 3-4 PM.

But it may not be a straight progression towards rain- several models, especially the NAM and CMC have the precipitation rate increasing enough about 5-6 PM that dynamic cooling occurs and a mix back to snow may occur despite surface temperatures rising above 32º.

Here’s a 3 frame gif of the precipitation type at 1PM 4PM and 7 PM–

Snow accumulations are still in the 1-2.5 inch range.

The storm significantly tapers and ends about 9 PM.

Once we get into the 48 hour time frame, we’ll have a better handle on the timing and fine points.

Update Wed 07:21 AM — Last night’s models continue a similar forecast as yesterday: Snow begins between 9-10 AM Saturday and mixes with and changes to rain late Saturday afternoon 3-6 PM.

The GFS GEFS and CMC are somewhat similar with a 2 or so inch  snowfall before being tamped down by sleet and rain.  The ECMWF is still coming in with about 1 inch or less.  Keep in mind:  the models have over-estimated snow totals so far this year.

Here’s a change:  Precipitation now ends about 8 PM, according to the GFS.

The storm is just in the 90-95 hour forecast period.  By later today, it will fall into the range of some of the higher resolution models, the SREF and the NAM.

I’ll update this evening.