eduggs

I'll be following the ECM-AI closely too. Anecdotally it's done great this year. That and the NAM for how far north mixing gets. The AIs plus CMC are pretty amped - it looks like that's where we're headed. The GFS is heavily discounted in my mind.

Sure everybody would enjoy a 6"+ thump on Sunday. But it's much more enjoyable if you don't have to sweat the pending sleet. The hypervigilance for the tell-tale signs of change over distracts from the experience.

Yeah the ratio thing is silly. But I still think a 12+ solution in possible. The 6z ECM/ECM-AI looked solid. Same with the 12z RGEM. We just have to hope for a flatter shortwave across the mid-south and mid-west in the run up.

This is the concern right here. The Delmarva, SNJ, CVA up to DCA were progged for 12+ for days (still might get it). But the NAM warms the mid-levels so fast that the duration of snow is too short lived for major (6+) accumulations. If this keeps trending in the same direction, we are at risk for a similar fate. It has happened many times in the past and often in hindsight people say it was obvious with a trof axis so far west. Fortunately the NAM is also sometimes too amped at this range. But it should not be completely dismissed.

What's wrong with describing what the model shows?

Disagree about the NAM. Look at this shortwave over OK at 72hr. Takes it straight to Chicago. That's sharper than 6z. Will take a primary and pronounced mid-level lows to WPA and then NYS. No way to block that mid-level warming Sunday afternoon with that upper level setup. Other guidance is less sharp... but NAM is good at this. Let's hope it's still beyond its accurate range.

God the NAM is super amped. 12z even moreso than 6z. That would end up as a lot of sleet - ZR even towards the end. Pray it's wrong. ECM, ECM-AI, and GFS looked solid overnight however.

Everybody knows wet means high QPF. Especially in this context. Not literally rain.

"Wet" as in intense rates, which is true considering it falls in about 12 hours. Temps between 700mb and 850mb surge during the day on Sunday and no longer support snow by Sunday evening for much of the forum. It's a high impact event but shorter in duration than some other models.

That's a sad look for Sunday night. Mid-levels too far NW resulting in a persistent primary low and no lift for our area.

It would be interesting if DCA outdid PHL, NYC, and BOS in terms of snowfall due to a stronger and longer initial overrunning. I doubt it mostly because of likely better ratios up north and possibly some tack-on snow at the end. But I guess it's possible.

The Euro is also faster to move out than the UK, ICON, and GFS. 12 hours of snow plus or minus and then dryslot/light stuff. Most of the steady precip. is done by 0z Sunday on the Euro.

Euro looks wet and warm. No major reversal to the north/amped trend but still a major event.

It's more amped. Powerfreak gets crushed up at Stowe. That's usually not great for our area.

This is the kind of NAM sounding that makes me nervous about sleet on Sunday. It's valid at 12z Sunday morning about 50 miles NW of Richmond, VA. Super cold surface & 850mb temps with 700mb temps -2C or -3C and the ptype is SLEET because of a pronounced warm layer near 750mb. The surface high can't save us from that. If the upper levels are amped and the mid-level lows which will track to our west are slow to weaken, our sounding could end up looking like that on Sunday afternoon/evening. That would be a bummer considering the depth of saturation through that column... would be a lot of QPF wasted as sleet.

3 out of 30 GEFS members develop a significant and deepening coastal SLP on Monday between NJ and LI (like the 0z ICON) and extend precipitation into early Tue.

Love the mounting evidence for a 1"+ liquid event. That's big dog stuff.

FWIW, I'm seeing about 1.3" for the UK and 1.1" for the GFS on Pivotal

With that prolonged easterly fetch some of the spots in SENJ and EMA that are favored for ocean enhancement could approach 2" liquid - a lot of which could be frozen. Great to see both the ICON and UK well over 1" liquid across most of our area.

The UKIE is ICON-esque! Maybe a tick warmer than the ICON but better than 12z IMO. Threatens a mix/dryslot or at least lull, but redevelops on Monday! Sweet run!

Through 18z Sat the UK is a little flatter than 12z. Still amped but a tick less. I'd prefer small run-to-run changes anyway, especially if they are in the right direction.

It's actually one of the best global models in the world. The only clearly superior model in terms of verification is the ECMWF.

I feel like the CMC has been doing better than the GFS this year. It's purely anecdotal but I don't trust the GFS at all.

In Europe, the ICON is considered a superior model to the GFS particularly out to 72 hours and across mid-latitudes. The GFS does not have the dominant perch amongst global models that it used to have.

The 0z RGEM is also a tick less amped than 18z but still pretty amped.