Under "What could change?" listed below I stated that if the "storm tracks further east, giving us much lighter snowfall of less than 4"" ... well, it appears to be tracking further east. I admit this is NOT what I was expecting. In fact, I was quite confident in my forecast when issued late yesterday afternoon. The consensus among the models was fantastic at 5 pm: ALL Models gave us 10 or more inches of snow ... many over a foot! The average between the GFS, NAM, NAM3km, RGEM, HRDPS, CMC, UKMET, EURO, ICON was nearly 12"! I even undercut the model forecast as it seemed too high, but I guess I got caught up in the "agreement" on a big storm and went higher than my 6" number I posted on Monday.
BUT the concerns for even 6" of snow began around 6 pm last evening. Observations at the time showed the initial precipitation area moving further east than expected. Plus the super short term models (forecast out 18 hours only) were not showing the development of heavy snow for our area in the morning.
They still are not. In fact, as of 6 am this morning only one model (HRDPS) predicts more than 4" of snow, the rest are less! Is this correct? Or is this an overreaction?
We will all know by 9 am this morning ... if the heavy snow is not seen anywhere on radar approaching our area, then 1-3" is what we get ... but if heavy snow is seen coming or is falling ... then 4-6" is coming.
No matter what I was overdone ... as are all forecasts private and public (National Weather Service). (One of the biggest errors in quite some time ... and the largest model forecast error in the last few years esp. since ALL were in agreement yesterday at 5 pm).
Think about it. If one predicts .75" rain, and you get .25" who really cares? Who complains? No one. It was supposed to rain, and it did. But what if that were snow? 7.5" forecast, yet only getting 2.5"? "A blown forecast. Terrible!"
Snow amounts are the perhaps the most challenging part of making a forecast, and this one could easily be off. A shift in track about 50 miles east or an intense band sitting over us ... and suddenly forecast for snow is up in smoke. The challenge is fun ... can you get it right?
No matter, enjoy.