Snowstorm

Summary: This storm will likely be the memorable one of this winter season. It really has not been a difficult forecast in the general details. A major storm moving from central California across the nation to the Mid-Atlantic coast and off shore. The biggest question during the week was, "would the flow in eastern Canada squish the storm to the south a little and cause a restriction on the precipitation shield?" 

The answer has come and the answer is no it will not. Now the only question remaining is, "where will the heavy snow bands set up?" These bands will lead to someone in eastern PA getting 24 or more inches of snow. Something to keep in mind. 

My current basic thinking: I am expecting about 1.5" of precipitation which at a typical 10:1 snow to rain ratio gives us 15" snow.  Take about 10% off for sleet, which could mix in especially Monday morning, and then that gives you about 13" snow.  

What Could Go Wrong: 

1. Snow is lighter and fluffier. So it piles up higher. This could boost snow totals by several inches without getting more precipitation. 
2. Heavy snow bands could sit over one location for several hours. This could greatly increase snow amounts. 
3. Milder air sneaks in longer than expected, cutting down snow totals. 

Details:  

Sunday: Snow begins after 12 pm. Becomes moderate to heavy at times. 
Sunday Night: Snow continues through 5 am. It should become lighter toward daylight. 
Monday: Ice may mix in during early morning from 5 am - 10 am. Snow becomes heavy at times after 10 am. 
Monday Night: Snow. Heavy at times. Becoming lighter after 3 am. 
Tuesday: Light snow ends in the morning. 

Total Snow:  10-14" with some sleet mixed in. Locally higher amounts possible. 

Update if needed Sunday Evening 6 pm.