Tricky forecast

I'm fairly sure I've used this title before, but this storm warrants the use of it again.  As I'm sitting here writing this, I have very little confidence in what will happen and therefore have no idea what to say.  I'm not saying I'm winging it, but it's pretty close to that.  Basically I'm going with my gut.

Let's start with model disparity.  It's been rampant with this storm and for the last few storms in general.  The difference from run to run is making it very difficult to come up with a solid forecast and hard for meteorologists to hold onto their sanity.  Every Met in New England who has been forecasting the last 4 weeks is earning all of their salary.  As it stands this evening, the models are forecasting anywhere from nearly no snow to 8-10".  The location of where this snow is expected to fall has been jumping around as well.

Nearly all the models do agree on one thing.  The storm passing south of New England, moving relatively quickly.  This path keeps most of the precipitation off shore.  The problem lies with a feature meteorologists call a Nor'lun trough.  I believe I have talked about this in previous blogs.  It is VERY difficult to forecast.  We've already had one of these this winter that was miss-forecasted by about 100 miles.  The result was a lot of busted forecasts.  Where there was supposed to be 4-8" of snow...there was NONE.  We are essentially dealing with the same situation now.  Will this Nor'lun trough even develop?  If it does, will be stretch far enough westward to impact New England.  How much moisture will be available?

All important questions that I don't have an answer to right now.  Anyone who says they are confident about their forecast is lying.  That is a fact.  I'm basically going to give you the most likely scenario and then update the forecast again tomorrow based on trends.

Here it goes:

As the storm passes to our south, there will be some light snow south of I-90 in RI, CT and MA.  This should generally be less than 2".  This snow will start falling midday on Saturday.  North of I-90, snow showers and flurries will likely develop mid afternoon and continue off and on through Saturday night.  A dusting to 1" possible.  Early Sunday morning is when the action could happen.  The nor'lun trough is expected to develop after midnight on Sunday morning and potentially persist through midday.  The range of affected areas will likely fall between the Outer Cape to Plymouth, MA northward to Portland ME.  Or it could not reach that far back and stay completely off shore.  I believe this one will actually make its was onto land, but it will be limited in its reach.  I think areas around Cape Ann north to Portsmouth, NH are likely to take the brunt of this storm.  It may reach as far inland as Manchester, NH, but I think that is a stretch at this point.

So look for a band of snow, oriented southeast to northwest from Cape Ann to Portsmouth, affecting Northeastern MA and Southeastern NH.  Here is where snow totals could top off around 8".  My official range is 4-8 for this area as a storm total.  Boston will be in the 1-3".  Worcester and surrounding areas, 2-4".  South central and Southwestern NH along with Concord northward to Plymouth, NH 2-4".  Southwestern Maine, 3-6".

There ya have it.  The hype that this storm got early in the week is essentially gone.  A lot of meteorologists are starting to get giddy about what the forecast models are showing for next weekend, but I'm not going to start talking about that just yet.

Thanks for reading!

-Jon