Monday Update on Wednesday’s Winter Storm

The forecast models continue to disagree on the exact track of the coastal storm and how quickly it strengthens. For those of you who wanted all snow in the immediate Metro Area, the models have trended toward a more inland track bringing the rain/snow line right into the 95 corridor. There is still time for models to adjust the track further east and any shift  eastward even by 25 miles would have a significant impact on how much snow, sleet and freezing rain falls in your neighborhood. For those of you in southern Maryland this is looking like mainly a rain event.

The latest North American Model (NAM)

The NAM model (image below courtesy Tropical Tidbits) tracks the storm system from near Raleigh, NC toward the NJ coastline and depicts a mix on Wednesday changing over to rain with little to no snowfall accumulations across the interstate 95 corridor. 

If the above track verifies, there would be little to no snowfall accumulation across the 95 corridor!

The Global Forecast System (next image, courtesy Tropical Tidbits) has been the most bullish for a significant accumulating snow in DC because it keeps the track of this storm system off of the NC coastline before it moves northeast and eventually out to sea. 

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Sunday Update on Potential Midweek Major Winter Storm

“Tim, your weather post yesterday was very scientific can you just get to the point and tell me how much snow is going to fall in my backyard on Wednesday?! ” – anonymous friend of mine in Arlington.

For those of you who are looking at your weather apps on your smart phones and have noticed that the snowfall forecast for Wednesday keeps fluctuating it is because those apps are averaging all of the ensembles from all of the various forecast models.

Yesterday I showed you the various ensembles of potential solutions within the Canadian (GEM), GFS (American) and European forecast models. Today I will show you the average of the ensembles from the American Global Forecast System (GFS) and the European models.

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