Sunday January 2 2022
In this report I will look into a few features of this developing storm and give my final call for snowfall. I have analyzed a lot of data from surface conditions to computer model guidance. My call is my perception of what will happen, which is why my snow map may differ from what you may see on TV, the NWS, or even computer models.
It will snow, and I know it does not seem possible after a few days in the 60s. But the same force that will bring in the cold air and rapidly develop the storm, will also have a sharp cutoff with dry air to the north.
Strong winds have already shifted to from the North.
Contrast:
Notes:
Southern Maryland, the warm air will lead to a start as rain, then chance to snow.
In the middle, there will be a ‘sweet spot’ where heavy snow will fall.
I’ve identified the cold air in western PA. This is also dry, and that is an important factor for the north edge of the impact snow.
Upper Level Energy
That final piece entering the Low Pressure will be injected in form Mississippi and Alabama tonight. This is what will get the surface storm to really crank up tonight.
The resulting storm track is expected to move through North Carolina just south of Virginia Beach.
Baroclinic Leaf: The boundary of that cold, dry air and the influence of the storm has created a band of clouds. That can indicate the outer reaches of the storm tomorrow. I’ve used this before, but the push of that cold air – and leaf- will advance south with the arctic air a little more. Where that sets up will be the northern cut off of snow. It will be within 50 miles of the Maryland/Pennsylvania line.
I’ve highlighted the plot on the HRRR Model for 10 PM. This may be a lagging behind by an hour.
Animation 10 PM Sun to 6 PM Mon
Here we can see the tight spin the storm once this final piece gets wrapped in.
I wanted to highlight this on the Water Vapor Satellite from 9 PM
See the animation below for the movement of this boundary and the moisture flow form the south feeding in to it.
I can stare at this for a while. The upper Level Energy does looks like is is moving in a little faster than the HRRR Model showed.
Notice the movement or apparent ‘shift’ to the North of the moisture from Georgia into Virginia and Maryland. This is easy to get lured in to, but need to watch if this is a trend or an optimal illusion.
Storm Animation:
Resulting Storm 3 AM to 6 PM Monday
This regional view shows:
3 AM and 5 AM:
Arrival of snow
Southern Maryland will start with rain for a few hours, then change to snow late morning to early afternoon.
Northern Maryland will be on the edge of that dry air. This is the wild card for metro snowfall. But the push of now will continue to try all morning.
11 AM to Noon:
Snow should star to taper in Washington and Baltimore.
Heavy Snow in southern Maryland
Afternoon/Evening:
Lower Eastern Shore will be transitioning to wet snow, and getting colder all afternoon. That region will get the bulk of their snow in the afternoon.
Temps and Winds:
Reminder that 20s are expected to spread across the state into the afternoon.
Winds will gust 25 to 35 mph, with higher surges on Delmarva.
Wind chills will be in the teens or single digits.
This is much lower than most model plots. I had suggested they were too high. But this is very close to my first call…
I accounted for:
Again, not all that falls will stick, but it will eventually and turn icy!
Last Winter Recap: My Old Outlook And Your Grades Of My Storm Forecasts
