Appologies for the late post on this but through one thing or another I have been slow to get to you my loyal US subscriber. Boy, what a spell of MILD looms to start December! Does that mean a mild the month overall will be warm, no I don’t think so.. More on that in just a bit.

Firstly, the snow event in the Mid-Atlantic lifting into the Northeast. It’s been amazing how contrasting the ECMWF is with the rest of the modelling. While te ECM was streets ahead of any model with Sandy, accuracy almost record breaking from 10 days out, this same model has simply not seen this snow event really at all. It’s simply not had this on the map and yet the GFS this time around has been adament of a snowfall and really from MANY days out, it’s showed snow in the general area where it appears it will actually snow total. Exact amounts remain to be seen but I think the moral is here, that no model is perfect, no model, no matter how good of a track record it has, will get it right everytime.

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This time around, it appears a point goes to the GFS. The above graphic depicting the snow for the M-A & NE is from TWC.

As you can see from the Current Weather map below off TWC, the boundary lies to the south with an area of precip now beginning to expand across Kentucky and this will spread east through tonight and into tomorrow. Notice the snow breaking out further north, this too will expand and intensify as the air cools. The low back across Texas will run the boundary east and as it does so, it’s the trigger the heavier precip, dynamic cooling which will help bring snow levels down nearer to the surface but this has complications.

Ok, so, here is the latest GFS snow forecast.

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Notice how it puts snow down from Missouri all the way to Missouri and the question for many is, do we see a covering in DC, Philly, NYC and Boston.

It appears right now that Washington will remains SOUTH of the snow and Philadelphia may even be slightly too far south BUT you guys may well still see an inch or so, it’s really from the mountains of WEST VIRGINIA through southern, central and eastern PA, NW NEW JERSEY and points just north and west of New York where a swath of 2-4, locally 6 inches is possible. Metro New York City may see a coating perhaps as much as 2 inches depending upon where bands form and really where you are in the city. I think points on the other side of the Hudson could see a few inches, while parts of Queens and Brooklyn may see nothing. Boston like both Philly and NYC appear on the southern periphery of this snow. This looks fickle. In my opinion, the mountains of eastern PA, NW New Jersey extending into Connecticut could  have either dissapointing 1-3 inches or it could go the other way and they get a decent 3-6 inch snowstorm out of this. Certainly the area outlined appears to be the area which SHOULD see the greatest snows out of this.

It will certainly be cold tomorrow with highs in the 30s with snow in the air in Philly, NYC and probably Boston.

Atmospheric River Heads For California!

Some newsworthy wild weather appears on the way to California all thanks to a trough reestablishing itself off and over Washington/Oregon, while systems ride the jet onshore bringing the usual wet and windy conditions to the PNW, it’s the deep plume of moisture which will eventually extend from Northern and central California all the way back to the subtropics which is catching the eye of meteorologists. This long fetch of deep moisture appears set to, stay near stationary for a few days with a constant stream of moisture pouring into California. The concern is there because of it’s origin which is sub-tropical and so it contains more moisture. Upwards of 10-12 inches of rain could well fall over the next 5 days but with mild air associated with this, snows may not be as prolific as you’d think, though go about 8,000 feet and we could see 2-4 feet out of this. With Northern California set to bare the brunt, a real soaking looks to be on the cards for the Bay Area all the way down to Ventura counties with showers extending into LA.

Here’s the general setup depicted well in a graphic courtesy of TWC.

Here’s the forecast precip over the next 5 days off the QPF model.

As for a warmup, well it appears to be coming for the majority of the US but all I would say is look out. Canada remains very cold, you only have to see what those temps were yesterday morning with a remarkable -38F at Lynn Lake, Manitoba. While you think, it should surely be as cold as that at this time of year, not really, that is January-like cold, not all that far from the US when you think about it and also, that very reading is COLDER THAN ANYTHING SEEN IN ALL OF LAST WINTER, now that’s impressive and it’s only November!

My advise would be to enjoy any warm up as the NAO and AO staying strongly negative (for now), deems any warmth, likely to be short lived!

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