Snowy week ahead

I haven't posted for a little while, as I've taken a break for at least the first part of Christmas break. And it was still justified as we experienced mainly rainy, warm weather during that period.

However, now we have moved back into winter. I did make one post on the main page outlining the potential storm for January 3rd. That threat still exists and I will talk about it later in this post.

First thing's first, just to bring everyone up to date, we have moved into a wintry pattern that will likely persist through the first couple weeks of January. As I predicted at the beginning of this month and in my winter outlook, we have moved into the negative phase of the NAO, and model guidence supports a -NAO block holding through the first half of January. The Pacific pattern is not quite as favorable. We have a strengthening +EPO that, without the -NAO, would have caused much of the east to blowtorch. But as it is, the -NAO comes to the rescue, and the eastern US, or at least the northeastern US, has many opportunities for snow ahead of us.

Three events are being monitored for this week:

1) Tonight - A strong shortwave will pass to our north. This wave will be starved for moisture. However with good dynamics, and a brief period of high RH and omega in the snow growth zone, there could be a couple heavy snow squalls that pass through the area later tonight (mainly after midnight). Total accumulation should be under an inch.

2) Wednesday - Another intense shortwave with associated surface low will cross Pennsylvania and exit just south of New England. All model guidence has been trending south with this storm. The GFS was the last to join the party and has really been failing lately for the record. As the low exits the coast, it will rapidly deepen into the 980's range as it passes just south of Cape Cod. This storm could produce some moderate w.e., and there is a general consensus for QPF of widespread .3" to .6" across northern CT, RI, MA, and southern NH and VT. In addition, omega of -15ub/s will be intersecting the snowgrowth zone with high RH, which will assist in some high snow to water ratios around 15:1 and locally higher. Axis of heaviest snowfall will likely lie near the Mass Pike, although there is definitely some adjusting to do. The GFS is still north of the rest of the guidence, with the NAM and Euro in agreement further south. This will be a widespread 3 to 6 inch snowfall for SNE and CNE, with likely a stripe of 6 to 9 somewhere in Massachusetts.

3) Friday N- Saturday - Low pressure moves into the Great Lakes with a secondary low developing and moving along the coast toward New England. Model guidence has been in agreement on the low rapidly intensifying to the 970's range near the region. However, there has been considerable discontinuity recently. Forecasts a few days ago were bringing the low inland, with rain for most of the region. Due to the developing block, these forecast tracks weren't counted on very much, and as expected, the models started shifting south and east. The Euro and GFS have showed big hits for interior New England in many runs. Verbatim, some of these runs support one to two feet of snow through Saturday. However, the GFS has been faltering about every other run with the intensity of the low, and recently the 12z ECMWF has a much weaker storm, with the latest UKMET and GFS following suit. At this point, just waiting for the 00z runs, as this sudden change doesnt make much sense. If it was just the Euro, then it would be disregarded as a fluke run, but the rest of the guidence coming in the same is a little worriesome. It is possible that the models digested some bad data. As I said, the 00z runs will clear it up ... hopefully.