December 19th-20 Storm Thread II

[wxeyeNH]

I'm curious about something. I often hear that the 6Z and 18Z runs are not as accurate as the 0Z and 12Z runs. Do they keep statistics that the off hour runs are less accurate or is this just gut feeling stuff?

[40/70 Benchmark]

lol I think it's possible for you too.

We'll see....I've already text some folks to expect a "life dusrupting storm" Sun-Mon.

I'm all in here.

[CT Rain]

Moon visible thru the clouds in the valley? while we rip S+ to your NE

lol probably not. It was sure nice to see the Euro ensembles come west but there definitely are a lot of members way outside the BM. I think it's possible an 18z GFS solution comes to fruition.

[Damage In Tolland]

lol probably not. It was sure nice to see the Euro ensembles come west but there definitely are a lot of members way outside the BM. I think it's possible an 18z GFS solution comes to fruition.

LOL..trolling phail

[A-L-E-X]

JB FTW

Worst case would not only close the Massachusetts and Connecticut turnpikes, but the Jersey, too. That is on the table. And I think you are seeing why I don't flip and flop back and forth with model runs. In fact, until all the players get onto the field from the Plains east, this is not really a done deal, but last night's GFS was simply the model having phase problems. Once it caught on, and it will still correct west a bit more... it figured it out. It's a matter of different runs seeing things different ways. You, though, as a weather enthusiast or beyond, should be focused on the whys enough to understand that until tomorrow, model runs out to sea should not phase you, since it's a matter of phasing.

You know, for an educated person, he should know that the "phase" in italics, is actually spelled "faze."  I hope that's the only mistake he made in that paragraph lol.

[40/70 Benchmark]

I'm curious about something. I often hear that the 6Z and 18Z runs are not as accurate as the 0Z and 12Z runs. Do they keep statistics that the off hour runs are less accurate or is this just gut feeling stuff?

I think they are slightly less accurate, but it's often exaggerated as to how much,

[CT Rain]

We'll see....I've already text some folks to expect a "life dusrupting storm" Sun-Mon.

I all in here.

I'll have a pseudo-meltdown if this doesn't pan out. I suspect you'll be joining me.

[CoastalWx]

lol probably not. It was sure nice to see the Euro ensembles come west but there definitely are a lot of members way outside the BM. I think it's possible an 18z GFS solution comes to fruition.

You were locking in 20" in that text you sent me.

[CT Rain]

LOL..trolling phail

I'm seriously not trolling I think an out to sea solution is still possible. I think many mets would agree. It's certainlly not the likely solution but it's still on the table IMO.

[CT Rain]

You were locking in 20" in that text you sent me.

Yeah I think odds favor a big storm. But I don't think it's a total lock, do you?

[40/70 Benchmark]

I'll have a pseudo-meltdown if this doesn't pan out. I suspect you'll be joining me.

You'll get your epic Ray-meltdown should this somehow devolve into a rusty coat hanger...or an inverted trough of VD stretching from the groin of an ocean low to MBY.

[weathafella]

I'll have a pseudo-meltdown if this doesn't pan out. I suspect you'll be joining me.

If this does not happen with this setup and guidance I may just jump off the Tobin and end it so not to endure any more winter of heartbreak.. Truthfully though, I would hope I'd learn my lesson and not post until the next round of guidance comes in...

[Damage In Tolland]

I'm seriously not trolling I think an out to sea solution is still possible. I think many mets would agree. It's certainlly not the likely solution but it's still on the table IMO.

I don't think any mets here think that

[DomNH]

We'll see....I've already text some folks to expect a "life dusrupting storm" Sun-Mon.

I'm all in here.

I expect a better NAM run during my usual C's halftime update and then a better GFS run later on. I'm with Kevin on this one...this does happen a lot with the GFS/NAM.

[Snow Bow]

You know, for an educated person, he should know that the "phase" in italics, is actually spelled "faze." I hope that's the only mistake he made in that paragraph lol.

i think that was an attemp on his part to be cleaver/funny. Failed... just stick to weather

[Damage In Tolland]

You were locking in 20" in that text you sent me.

He is one of the few mets that actually thinks the gFS is worthwhile to use

[CoastalWx]

I'm seriously not trolling I think an out to sea solution is still possible. I think many mets would agree. It's certainlly not the likely solution but it's still on the table IMO.

It's also relative to where you live. I think eastern areas have a good shot at something more than advisory, but I wouldn't rule out a correction east. Maybe I'm wrong, but I don't see this whiffing all that far to the east.

[Baroclinic Zone]

Yeah I think odds favor a big storm. But I don't think it's a total lock, do you?

Not until tomorrow night.

[ORH_wxman]

I don't think any mets here think that

This could definitely still whiff, but I'd favor a hit over that right now.

[Logan11]

I don't believe the US models really and I don't think I would let the 18Z runs phase you. How many times have we had the Euro accurately call a cutter and the stupid GFS comes in further east and offers hope. Well enough said..... it will come back to the Euro by tomorrow night at 0Z or so.

The Euro is onto this that's all you need to know. I really don't see it shifting east now that we in its wheel horse so to speak.

I'm curious about something. I often hear that the 6Z and 18Z runs are not as accurate as the 0Z and 12Z runs. Do they keep statistics that the off hour runs are less accurate or is this just gut feeling stuff?

[CoastalWx]

Yeah I think odds favor a big storm. But I don't think it's a total lock, do you?

Just kidding around.

No it's not a lock at all, but I think the odds are there for something good in eastern areas at least.

[Confuzzled]

I'm curious about something. I often hear that the 6Z and 18Z runs are not as accurate as the 0Z and 12Z runs. Do they keep statistics that the off hour runs are less accurate or is this just gut feeling stuff?

I think the 12z and 0z runs are generated from raob soundings and surface data whereas the balloons aren't launched at 6z and 18z. So the initialization upper air data of the intermediary time frames is probably less empirical. In light of that I would think the 00z and 12z must be more accurate but how much, I have no idea.

[Damage In Tolland]

This could definitely still whiff, but I'd favor a hit over that right now.

I don't see any possibiltiy of a whiff. A shift east sure..but not a whiff..not with the Euro locked in now

[40/70 Benchmark]

Just kidding around.

No it's not a lock at all, but I think the odds are there for something good in eastern areas at least.

According to tube socks, ene doesn't have a better chance than w areas.

[Organizing Low]

We'll see....I've already text some folks to expect a "life dusrupting storm" Sun-Mon.

I'm all in here.

wow thats ballz to the wallz

i used to do things like that, now i wait till within 72 hours before offering a comment

[Logan11]

You're a lock to be buried ....nw of BOS there. It doesn't even matter if you dry slotted and went up to 33 at some point because the front end would already have buried you.

According to tube socks, ene doesn't have a better chance than w areas.

[CT Rain]

This could definitely still whiff, but I'd favor a hit over that right now.

Absolutely. 100% what I think.

[CT Rain]

I don't see any possibiltiy of a whiff. A shift east sure..but not a whiff..not with the Euro locked in now

So Will is wrong?

I like Harvey's 75% big hit kinda deal for Boston. I think it's about 50/50 in CT.

[ORH_wxman]

I don't see any possibiltiy of a whiff. A shift east sure..but not a whiff..not with the Euro locked in now

Well the whiff possibility I think is definitely low as it would be a catastrophic failure of the Euro and its ensembles inside of 96 hours...but given how tough this pattern has been on guidance, I can't really rule it out.

[Mr Torchey]

I want to reply to the "18z suite is crap since they use old data" nonsense (mostly from the previous thread). Think of it like this, if an 18z model initialization used NO data/observations at all, it would look identical to the previous cycle's run (i.e. no observations were used, a 120h forecast from 18z would look identical to a 126h forecast from 12z). This is explicitly true for global models with are cycled, and only somewhat true for the NAM and other regional models that use partial cycling. Additionally, and 18z regional model run will have the advantage of using a new global forecast for boundary conditions.

In a time mean (average) sense, the 18z run will always be better than a 12z run since it DOES use updated observations, improves the analysis, and therefor improves the forecast. For an individual case (especially when looking at something like downstream energy transfers, phasing, coastal cyclogenesis), very small changes to the initial conditions can have extreme impacts on the model simulation (resulting from large error growth rates for the storm of interest, nonlinearity, etc.)....hence all of the model flip-flopping the last few days. So even though the updated forecast will be better in a global/verification sense, it could potentially make some component of that forecast actually worse (i.e. having a storm develop too far off shore, too quickly, what have you).

Lastly, even though we don't have much in terms of raobs (which are awesome obs, so we intentionally draw closely to them) at 18z, we have a ton of other observations (satellite radiances and derived products, aircraft data, wind profilers, surface observations, satellite cloud track winds, GPS radio occultation, and so on).