The Post Christmas storm threat is still vey real

[CoastalWx]

06z gfs I think will be a little east.

[skierinvermont]

The s/w is still at the base of the trough at 54.. will be east of 00z I think

[CoastalWx]

Yeah it's a little weaker with the s/w rounding the base of thr trough and doesn't tuck the low quite as far west. I expect models to waffle a hair at this range so we'll see what 12z does.

[nzucker]

north central PA jackpotted with 30".. 6" nyc 11" northern suburbs 13" POU .. 6" BOS 15" ORH... heavy snows 10"+ for most of PA, NY, VT, NH, ME, stripe of 20+ in PA and upstate NY

Nice to have the KU book on hand, need to buy myself a copy but it's serious money for that tome.

6z GFS looks crappy at 60 on RaleighWX...well east of 0z despite looking a bit better at H5:

[cpickett79]

So Euro from what I read, 964 SW of BM pretty identical to 12 Z cept slower, Cape gets 1.5 Taunton Bob 1 Will. 25 BDL.1

SW? if that is so that qpf field would be mighty tight. seems tight anyway.

[nzucker]

Moderate hit for the Cape and BOS at 78 but nothing too exciting:

[skierinvermont]

6z GFS looks crappy at 60 on RaleighWX...well east of 0z despite looking a bit better at H5:

Yeah it ended up worse at h5. It's waffling.. hopefully it brings back the more extreme stuff. This looks more like the EC

[nzucker]

Yeah it ended up worse at h5. It's waffling.. hopefully it brings back the more extreme stuff. This looks more like the EC

It was weird...the ECM and 6z GFS both looked better at H5 up to 48 but then declined quickly and turned into garbage. The storm on the 6z GFS also doesn't produce that much precipitation for such an intense low in the 965mb range. Here is the QPF total for the storm on 6z...Cape Cod does well but they may have mixing issues or poor ratios due to warm surface temperatures...you get 3-5" and Boston probably sees 6-8" or so....just a dusting here in Westchester, NY:

[CoastalWx]

Yeah it ended up worse at h5. It's waffling.. hopefully it brings back the more extreme stuff. This looks more like the EC

It's actually east of the euro. Hopefully we can get it to go west a little.We have like 72 hrs. Euro ensembles may have been east initially, but end up a little slower than 12z. I don't see a huge difference but it may have ticked east.

[CoastalWx]

Cape would be sn with the GFS. Big VV's down there.

[skierinvermont]

It was weird...the ECM and 6z GFS both looked better at H5 up to 48 but then declined quickly and turned into garbage. The storm on the 6z GFS also doesn't produce that much precipitation for such an intense low in the 965mb range. Here is the QPF total for the storm on 6z...Cape Cod does well but they may have mixing issues or poor ratios due to warm surface temperatures...you get 3-5" and Boston probably sees 6-8" or so....just a dusting here in Westchester, NY:

If you look carefully you can see the features that makes the 6z inferior to 00z by 48 hours.. the S/W is not as strong over MS/AL, the leading S/W over SNE is stronger which knocks down heights a little and pushes things offshore in later frames (leading s/w interfere with cyclogenesis); and the s/w over MN is slower which may be bad as well because I think it is helping to tilt the trough on the 00z

[nzucker]

It's actually east of the euro. Hopefully we can get it to go west a little.We have like 72 hrs. Euro ensembles may have been east initially, but end up a little slower than 12z. I don't see a huge difference but it may have ticked east.

Why does this storm not develop a complete CCB until it hits Nova Scotia and Newfoundland? Is that because it doesn't become vertically stacked enough early on?

You can see that the heaviest frames of precipitation for Cape Cod are like .4" QPF whereas it dumps almost 1" QPF in 6 hours on the Canadian Maritimes despite a lower central pressure? Is this because of the development of the mid/upper levels or just because the ocean is enhancing the system's moisture as it travels more over the water?

[skierinvermont]

It's actually east of the euro. Hopefully we can get it to go west a little.We have like 72 hrs. Euro ensembles may have been east initially, but end up a little slower than 12z. I don't see a huge difference but it may have ticked east.

Yeah.. I would not be shocked at all if it shifted 100 miles at this lead time.

[nzucker]

If you look carefully you can see the features that makes the 6z inferior to 00z by 48 hours.. the S/W is not as strong over MS/AL, the leading S/W over SNE is stronger which knocks down heights a little and pushes things offshore in later frames (leading s/w interfere with cyclogenesis); and the s/w over MN is slower which may be bad as well because I think it is helping to tilt the trough on the 00z

Yes, these are fine points...I'd rather have this type of discussion LOL. It lost a ton of vorticity in the southern shortwave, and you can really see the entire northern stream is lagging by 48 hours including the energy over Wisconsin AND the stuff up by Hudson Bay. Without that energy fully interacting with the trough, the storm is a lost cause for most of the I-95 corridor except perhaps Boston. The polar jet just doesn't seem ready enough to phase into the trough, and that means you go from 8-12" on 0z to 3-5" on 6z...I go from 4-8" to essentially a dusting. It looked as if the southern stream was deepening more early on in the 6z GFS run, but it just didn't involve the northern stream as much and there is that pesky overrunning-type s/w which knocks down the ridging over the East.

I am seriously thinking about chasing this storm in the Canadian Maritimes. I want to see that deformation band and I know this winter is going to suck here.

[moneypitmike]

I was excited to see the 00z GFS. Got my hopes up that I'd at least get to break out the snowblower. The ensembles, EC and 06z GFS are pretty disappointing. I'm pretty convinced will have a big storm that bring decent snows to the Cape and other areas of far eastern MA. I think outside of that, there will be a lot of Cape envy. A lot of folks (population centers) may end up with good advisory levels. Much of the area though will fall short of that.

As for me, I will enjoy my flurries and begin to focus on the next one.

Then again, the new NAM runs in about 3 hours.

[moneypitmike]

HPC's not buying the 00z GFS.

GIVEN A LACK OF GLOBAL MDL OR ENSEMBLE

SUPPORT FOR THE 00Z GFS...WILL STRAY AWAY FROM THIS...IN FAVOR OF

A 12Z ECMWF/18Z GFS COMPROMISE.

Just took a quick glance at my forecast, and it has us above freezing at the end of the week. That would add insult to injury.

[MaineJayhawk]

I was excited to see the 00z GFS. Got my hopes up that I'd at least get to break out the snowblower. The ensembles, EC and 06z GFS are pretty disappointing. I'm pretty convinced will have a big storm that bring decent snows to the Cape and other areas of far eastern MA. I think outside of that, there will be a lot of Cape envy. A lot of folks (population centers) may end up with good advisory levels. Much of the area though will fall short of that.

As for me, I will enjoy my flurries and begin to focus on the next one.

Then again, the new NAM runs in about 3 hours.

Agreeing with what you say. Sounds like great snows for the Cape and adjacent areas and a "nice blanket but nothing exciting" snow for the balance of the area. 0z GFS sucked me in more than it should have. Naughty, naughty GFS.

[free_man]

enjoy the light dusti g interior folk. sunday roadtrip to the cape looks likely

[moneypitmike]

Agreeing with what you say. Sounds like great snows for the Cape and adjacent areas and a "nice blanket but nothing exciting" snow for the balance of the area. 0z GFS sucked me in more than it should have. Naughty, naughty GFS.

I'm glad I didnt' stay up for it. I'd have had a much longer state of expectation had I done so. The benefit of checking the models in the morning is, like watching a movie, you can fast forward through 4-5 hours of "real time" in about 30 minutes to get to the good stuff. Keeps the excitement of the 00z gfs from building as you quickly see the ens and EC.

I suppose I'll look at the 12z run, but (Pete might call me negative), this is going to be a whole lotta "boy so close" for many, many people.

Congrats, Phil!

[MaineJayhawk]

Probability map for 4+ inches. The 8+ map has Cape Cod at least 10% probability.

[moneypitmike]

Probability map for 4+ inches. The 8+ map has Cape Cod at least 10% probability.

Post the 12z EC run from a few days ago (Tuesday??). That was sooooooooooooooooooooo much more entertaining to look at!

Merry Christmas Eve, everyone.

[moneypitmike]

As bad as the NAM is being criticized, I like it because it has been steadfast in giving me .1" of snow. How sad is it that I'm now pulling for the NAM.

[Damage In Tolland]

All in all things still looking like they're on trck for a powable snow from 1-91 east. the one area still in question is can we get plowable snow back to west of 91 or just an inch or 2. Euro track would drop about 3-6 here. Nice to see the NAM coming on board

[moneypitmike]

I think that BOX has just decided to keep this in all of their AFD's. They'd be better off just putting a disclaimer in bold at the start of any discussion or forecast for all time.

CAUTION IS ADVISED IN LITERAL MODEL INTERPRETATION AT THIS POINT.

[moneypitmike]

All in all things still looking like they're on trck for a powable snow from 1-91 east. the one area still in question is can we get plowable snow back to west of 91 or just an inch or 2. Euro track would drop about 3-6 here. Nice to see the NAM coming on board

With all due respect, Reverend, I ithink you're on crack. lol

[CoastalWx]

Why does this storm not develop a complete CCB until it hits Nova Scotia and Newfoundland? Is that because it doesn't become vertically stacked enough early on?

You can see that the heaviest frames of precipitation for Cape Cod are like .4" QPF whereas it dumps almost 1" QPF in 6 hours on the Canadian Maritimes despite a lower central pressure? Is this because of the development of the mid/upper levels or just because the ocean is enhancing the system's moisture as it travels more over the water?

The euro actually has a pretty nice ccb over the Cape, by hr 78. This storm moves fast originally which may limit inflow until it slows a little. This is exactly what it does towards hr 78.

[Damage In Tolland]

With all due respect, Reverend, I ithink you're on crack. lol

What are you talking about? A storm that tracks near the BM always drops accumulating snowfall here. Again don't focus on qpf placement or amt.s .This is how you always get into trouble.

A strong storm where it is on the Euro will throw a good deal of snow much farther west than what you think. Nothing has changed at all overnight..

[CoastalWx]

06z ensembles are a hair west of 00z I think.

[CoastalWx]

Man 50 miles is everything. Please let us get a Christmas miracle.

[Damage In Tolland]

Man 50 miles is everything. Please let us get a Christmas miracle.

50 miles means you go from 4-8 to 12-18 and I go from 3-6 to 8-12

We can do it