Tuesday, January 19, 2016

Big weekend noreaster still appears to far south for us Vermont powderhounds

The valley is enjoying a nice taste of winter and everyone seems very thankful for that. We've enjoyed a nice stretch where fluff seems to be arriving daily. Mad River has gotten more than 20 inches of snow in the last 8 days with more falling as of Tuesday morning. Most of the discussion relating to weather has shifted to the late week and weekend potential noreaster.

The storm is the work the work of the powerful southern branch of the jet stream which has, as expected, been extremely active thanks to the work of the strong El Nino. The storm will not receive any help from the relaxing polar branch of the jet stream which will recede into Canada as this storm begins its interaction with the Atlantic Coast on Friday. The proper ingredients are in place and there is no risk for mixed precipitation or rain. The storm will strengthen to about 990 mb and proceed northeast from there. 990 mb is quite strong but not historic as far as noreaster's go. It's the moisture which makes this event particularly distinctive. The Gulf of Mexico will provide a large share of it on Thursday and the Atlantic Ocean will provide additional fuel for the fire Friday into Saturday.

Speaking for us Vermont powderhounds, the track of this system appears problematic. The storm reaches the Virginia Tidewater late Friday which is terrific and then heads northeast. We just need the storm to head more north and less east. With the pattern more or less relaxing around the storm, there is nothing to prevent the storm from moving in any particular direction. Simple continuity of momentum will take the system too far south but sometimes the natural baraclinicity provided by the coastline can guide these systems farther north verses expectations. Recall, the Valentines Day storm of 2007 was forecasted to be a coastal hit only and the track shifted north at around the 10th hour. I wish I could say this was more likely again but it isn't. Models have converged and remained relatively consistent with the trajectory of this storm. The areas most impacted by snow would be interior Maryland, eastern Pennsylvania, northern New Jersey and southern New England. Vermont would get mostly missed with the exception of perhaps the southern third of the state.

A brief window of milder weather arrives in the wake of the big noreaster. Not extremely mild but Sunday's temps will reach the high 20's with the help of some sunshine and Monday's readings could reach 30. Winter will make a return next week however with snow coming from a clipper system late Monday or Tuesday. The pattern will then re-amplify and allow for another potential winter storm. There has been no agreement on this hypothetical midweek system but it remains a possibility for now.

Still not liking the look of early February right now. A jet tightening in the Pacific will try very hard and cause a jet trough consolidation in the western United States. This is not what we want at all. We can hang our hat on the Arctic Oscillation however which is not expected to switch signs but rather remain slightly negative or neutral. This might thwart the  massive onslaught of mild weather which was featured during most of December.


1 comment:

Unknown said...

I was considering driving to Boston area on Saturday and driving back up that night, should I not bother with the storm hitting?