February 14 – Happy Valentines Day. The good news is that we have turned the corner as the coldest of this arctic blast is moving away. With Presidents Day tomorrow, there is less of a concern for the snow on the way impacting schools since they are closed. But there still is concern for traveling and those working. It will snow. It looks like the event will start later, but the afternoon and evening will show increasing snow. It will also show the intrusion of warmer air from the south and a change over to ice, and eventually rain from the south. The big question is about if and where the cold air will hold, lingering the ice longer into Tuesday. Below is the comparison of the Canadian (colder) and GFS (warmer) models. But also what hint to look for before this happens.
When will it begin? The signal that will show storm track then:
This snapshot at 7 AM Monday shows the snow west of Baltimore and Washington. This is a little later, showing a slightly slower system. This will allow the High Pressure to move away and the storm to cut northeast. But where? The hint will be where the High Pressure is located. The colder Canadian shows that centered over northern New England. The warmer GFS shows that southeast off the New England Coast. The plot on Monday before the snow reaches us should then give us a clear idea of how this will play out. The air is so cold and dry that it might show on radar but be virga. It will take a few hours to eventually fall. But plan for increasing snow afternoon. Note: The ground is frozen, so all that falls will stick.
Tuesday Morning Split: Ice I-95 and west, or Rain
It is a good bet that if you live in the big cities along I-95 or to the south/east then you will have rain Tuesday morning. The big question will be the northwest suburbs. Note: The ground is frozen and will take some time to thaw, Air temperature at 6FT and warmer clouds producing rain, will still have freezing on impact for a while. Also- The northern Chesapeake is frozen. Wind direction will be key. An east will will not warm as much as it did last week. But a south wind (GFS track) will warm the air faster.
Warning Vs Watch Vs Advisory
This is the morning map from The National Weather Service.
Winter Storm Warning are for areas that are likely to see the most snow and then remain icy into Tuesday.
Winter Storm Watch remains in places that are still on the fence of whether the ice will hold, and how much snow will accumulate before the change over.
Central Maryland/DE/Eastern PA (highlighted in yellow): There will be snow Monday! But the amounts will likely keep it in the criteria for an ‘Advisory’. When The National Weather Service upgrades today, I expect that will be the case for all counties west of the Bay and the northern half of the Delmarva. Check out the model snow projections below showing the places in the 1 to 2 inch range.
Canadian Is Colder…. Storm Track Through Maryland