We begin this Monday Saint Joseph's Day morning with some coffee and a zeppolli! It is on the cold side again as high pressure is building southward into Eastern Canada and New England. Temperatures are starting out in the 20s to near 30 and we should see a fair amount of sunshine today. Highs should reach the 40s though areas in South Jersey and Southeast Pennsylvania could see upper 40s to near 50 while inland areas struggle again just to get out of the 30s.
We are beginning to see the signs of the next storm system on the satellite this morning. We are seeing the distinct hook feature in the center of the picture over the Plains which is the signature of the upper air disturbance. This is moving east as advertised and on schedule. Some Gulf moisture is beginning to get involved here as the low heads for the Tennessee Valley tonight and during Tuesday. Look for clouds to increase here overnight and on Tuesday.
Now as far as Tuesday goes we will see precipitation break out across Virginia and Maryland and spread into Southern New Jersey and Southeastern Pennsylvania during the day. It will probably start as rain but then mix with and change to sleet and then snow. It will make its way northward and gradually overspread all of New Jersey, the Hudson Valley to about Poughkeepsie and then snake along eastward to along Route 84 in Connecticut. Snow continues during the day Wednesday. Accumulations are going to be very tricky here for a number of reasons.
JOE'S SNOW FORECAST TUESDAY WEDNESDAY MARCH 20-21, 2018
First off we have the usual sun angle issues this time of year so what falls on roads verses colder surfaces are going to be 2 different things. On the other hand, temperatures are likely to be cold this time around, near or below freezing especially away from warmer urban centers. This may compensate some. Also trying to figure out how much falls at night verses how much falls during the day isn't easy. Expect a lot of variability out of this. Rural and elevation driven areas will get more than warmer urban settings like around New York City, Philadelphia, & Newark/Jersey City among others. All of this should come to an end during Wednesday night from west to east. Weather conditions improve on Thursday and the snow melts!