SnowGoose69

The redeveloping of the low is not the best thing in the world as it might cause a screw zone. Not to the extreme we see in clippers but this is a case where some dynamics could be lost if we have a hard weakening and transfer to a coastal.

I've seen the Canadian sometimes nail these nasty confluence events before. We've seen a few storms where its causing cirrus sniffing everywhere and the GFS/NAM/Euro were still hits and the Canadian was right. I wonder if it might be due to it having better data in Canada near the Maritimes in those types of setups. Its certainly one reason I'd be a bit worried it was the most south so far at 00Z.

This is a SWFE. Most people don’t realize that because it’s so far south relative to normal. They usually do not show any northward movement that is notable til the final 72-84 hours most of the time and sometimes not til the final 48. I had said by the time this was 96 or so out we wanted the jackpot to be DC preferably or northern to central VA. If it was there we’d be in good position to get snow, albeit not the jackpot. I still feel the jackpot zone in the end though might end up southern PA to southern NJ. So maybe a 50 mile shift from what we currently see

I sort of think the whole system is gonna eject out way faster anyway. If that happens its likely just a deep south winter event.

As forky pointed out the other day too, there is going to be convection for sure with this in TN Valley which might have a downstream impact on track too. It likely also will totally shaft someone on QPF across IL/IN/OH somewhere. Thankfully we never have that problem here

There's been a joke for a few years that the ICON is better at 120 or 144 than it is inside Day 4 and I've honestly felt thats overall true. I've seen many instances where a storm is inside that range and the Euro/GFS/UKIE/NAM all agree and the ICON is nowhere close yet 2 days before it had that idea the others all now agree on

I tend to ignore the ICON once inside 96. It actually seems to perform better on the end result often times beyond that, once inside it can do wild stuff. The NAM had a classic NAM run at 18Z for sure, not in a good way unless you're in a small niche of MD.

It sucks in -NAO/+PNA regimes...the one thing maybe going in its favor here is the Pac is still screaming so the S/W traverses the country insanely fast. The Euro has been owning the GFS for the last month or so on the grading numbers.

They would not get 6-10 in that scenario probably because the convection would rob moisture

I'd rather be in Philly or Richmond right now. DC you just know its moving one way or another given we are still 120 hours or more out.

With a strong -NAO not nearly as often. Some of the least track insanity inside 72-96 occurs in patterns like 09-10 or now when things are slowed down by the NAO. You won't often see massive changes.

There has been a wild snow drought in places like GSP/ATL. Those are not exactly snowy places but they also do not go 5 plus years without a 1-2 inch snow event that often, they both have gone I think 7-8 now

Always seems to me when models see raging confluence at D5-8 in a solid -NAO pattern they always overdo it and it inevitably ends up less suppressive as we get closer. The patterns where the blocking is not as raging and they pick it up late inside D5 its like a never ending congrats southern hemisphere as we get closer like March 2013

Funny thing is that would never happen. Having forecast for that area for years lows needs to usually be 1000mb or weaker or they'll track over cntrl or northern AL/GA. Its very rare you can get a low to deepen into the 990s and remain all snow in ATL, the track will usually end up over or near them

18Z GFS congrats Valdosta GA lol

the NavGEM is north of the GFS which is nice

The ATL measurable snow drought of nothing over 0.5 for 7 years should end next month.

Might be some showing that funky evolution where somehow the surface low sorta survives the meat grinder enough to exit into the Atlantic and then redevelop and throw moisture back. We've seen Op solutions with that the last 2 days.

It needs to be near BWI-RIC by 4 days out, its gonna be hard to get it back from anywhere south of RIC but I think if BWI is the bullseye at 96 unless this is the 1 in 10 case where confluence is not being overdone at Day 4 its coming north. I still don't know if it can come back enough those to save most of this subforum. Maybe NYC and SE parts of SNE

By 96 we probably want to see a consensus somewhere between the GFS/Euro. If it holds there through 96 if we go off historic tendencies it probably will gradually come north. I've not seen too many cases where confluence at this range is not overdone. Don't want to have to be bringing it back from Raleigh or Charleston though. Parts of SNE outside of the coast might be close to out of it though at this point.

Its crazy that today we've got convection in the area tonight. The OH Valley is getting a perfect track low and its not even snowing north of the low. If you were still living in the 1980s when models only went out 5 days you'd have no idea what was coming

The 18 upgrade was mostly focused on improving its accuracy over mainland Europe. It did take care of the progressive bias it was having in the US though inside of 72 after the 2014 upgrade. You could almost always shift every storm 50 miles north and it would work. It definitely caused a more amped Op bias though from 84-120.

for whatever reason the last 10 or so years it seems the Euro in winter does better in years where either its an El Nino or the PNA is + and the GFS does better in La Nina -PNA years.

the first storm to me the UKIE idea might be more accurate. I think the ridge out west is just way too far west that even with the -NAO the storm will cut

Somehow the NAO/AO both averaged negative that month, the first 10 days might have skewed it enough. That looks very Feb 2011 like from my memory. at least late month