Feb 20-22nd Could things be getting a bit more interesting?

As we have been stating for some time now..the outcome of this time period really depends on where the Polar Boundary sets up. Essentially waves of low pressure should ultimately ride along this boundary and if you are to the north you should be cold enough for snow but if to the south you would more then likely see a plain rain scenario.

Guidance has been all over the place. We have seen the GFS north with this boundary and showing a Lakes cutter. We have seen the GGEM at some point and time showing a Lakes cutter and we have seen the UKMET as well also show a Lakes Cutter and I believe the ECM also at one point and time showed a similar solution to a Lakes Cutter.

Then we have the timing issue. Does the energy eject slower or does it eject faster? As was noted before with systems from the SW they generally like to eject slower and we favor the slower ejection which could result in a slower moving storm system.

One reason that could potentially lead to a slower solution is bringing the bias of the NOGAPS into play which is a very progressive model and how it shows a slower solution.

Here is todays 12 Z NOGAPS @ 144 hrs. Now , normally you would think with its bias that it would be as fast as the rest of the guidance but its slower. So this leads to the thinking that this could be slightly slower then what guidance is suggesting.

The 12 Z ECM today basically keeps the system to the south because it has the confluence across the NE too strong which suppresses and then acts to shear out the system.

While the operational is further to the south ..the means on the other hand are further to the north.

At this point and time we feel that the ECM is actually too far south with the Polar Boundary and hence that makes the over running to far south as well. Reasons for this is that the GFS has been further to the North and the GGEM is also further to the North… That brings us to the GGEM

The GGEM would be supportive of a 3-6 inch snowstorm across the region generally south of NYC.

The 12 z GFS continued to show its track into the lakes but as of 18 Z has become alot more interesting and has trended south. Not as far south as the ECM however..

Current thinking is that the GFS is still too far to the north but at this point and time it is the trend of coming south and colder that is worth Noting.

At this point and time we feel that a compromise solution or track is probably the best scenario and that would be that the boundary will probably set up right across or just south of the MD/PA border and these waves should proceed generally south of the region but not so far south that they would not effect the area.

We still feel that a light to moderate event is potentially on tap for the region. Again, though lets be clear..it all depends on where that polar boundary sets up. Based on the teleconnections we do not see a really strong push of cold arctic air into the region but with high pressure over SE Canada this would be able to bleed cold enough air into the region from about the PA/MD line north. NAO is neutral..PNA is also around neutral and the AO looks to be heading towards the neutral slightly negative area. All this would support colder air bleeding south but no massive push southwards.

We will continue to monitor this situation and keep our readers updated on this potential.