Bob Chill

Like I've said before. Looks like a bread and butter west track/eroding CAD situation. Odds favor some frozen precip. Whether or not it's a memorable or "good" event will depend on how much QPF hits while the column works. Euro is stepping back but it's going to wobble around every 12 hours for a few days. We'll know by Wed if it's going to be a decent snow event or a quick small hit that gets washed away.

Yea, that and the track is a little further north than 0z so could cancel out improvements with the antecedent airmass

Euro ticking colder/stronger with the high leading into the 18th. Very noticeable by hr96. Should be a decent run (famous last words)

@psuhoffman Good analysis on the next window. I do find it comforting that even if that window sucks.... ens guidance looks sweet AF down the line. This is a cold/stormy/active look. Progressive flow but great height pattern in the atlantic to fight off cutters. Of course anytime the NAO is + a cutter can happen but if we aren't going to have a block I'll be perfectly happy with this look through mid March.

What a weenie run... lol

Looks good to me and room to improve...

All ops are converging on a colder start to the storm next weekend. The 0z EPS ticked up quite a bit with # of solutions that have snowfall in SW VA. Now the ops are agreeing with that. We're getting close to locking in some sort of winter wx event now. By this time tomorrow if everything holds or improves it's probably game on here. Warm fronts can be modeled decent 3-4 days in advance so these op runs are at least believable.

That "weird brief warmup" that the gfs op keeps showing is actually supported by the ens now. EPS really picked up on it on the 0z run. Makes sense as the pattern change is a step down process and not like Feb 2015 where winter blew in violently with a single front. Our change to better conditions this time looks more like a multi step process.

I'm not even sure this is an ice sounding. That's not much of a warm nose at all honestly...

This is slowly morphing into a bread and butter west track with 2-6" of snow before ice/dryslot. It's looked like that general setup since d10. Nice to see us better off today than the past couple.

Notable overnight shift with deeper CAD leading in and not just the surface. Always a good sign with a west track when ROA gets snow from a warm front.

diggin these incremental shifts with better confluence/less latitude gain. ICON continues @ 12z.

My guess is if the warm front hits us it will be mostly or all frozen before dry slot and rain. That's our typical climo for this general setup. How much qpf falls is a question. These parts of a storm generally don't drop more than .5 qpf when the low tracks so far west. The juicy cad tracks are up the apps. This one is almost certainly tracking further west than that.

Not going to matter. Storm is slower and weaker this run. We need precip in here as fast as possible. If the storm ,keeps slowing down we'll need incremental improvements north of us

Northern stream creating more confluence on the 0z gfs later this week. Improvement starts early and by hr84 it's obvious

It's a good setup for a good cold shot. D9-10 850s on the eps were -10C. Pretty big departure for that far out in time. If we have a persistent -epo like the ens want us to believe... we could get quite a few cold shots. Quite the turnaround from the last 6 weeks.

I loved the 06 storm. 05-06 would have been a total dud without it. I remember not needing a jacket the next day. I'd have to look it up but my brain remembers 15" in my yard and it was not high ratio snow. Mashed potatoes

After weeks of butt ugly analogs...some interesting ones showing up now...

Think of it like this. Even when northern Canada or the Arctic Circle temps are "above normal" that still means below zero. What all that ridging in the high latitudes does is it displaces cold continental airmasses southward into the mid latitudes. Above and below normal temps are relative to latitude. A +20 arctic circle airmass is -10 if it gets pushed over us. The panel you are looking at isn't big cold but it's below normal and that's all we need during jan/feb.

We'll have to wait and see if it's right but week 3 on CFS weeklies looks exactly like d15 on the ens. Shows a +preip anomaly along the east coast as well.

Yep, close to a lock that we get a period of deep cold sometime after next weekend. 18z gefs has a really nice look d10-13 for a SE storm. A lot has to happen first so focusing on anything specific is like a dog chasing its tail. All systems go beyond d15. The end of the EPS and GEFS both look the same and it looks pretty damn good. One thing that wasn't around much in 2014 and 15 was the southern stream. Ensembles imply active southern stream down the line. Hurry up and wait but at least we seem to be waiting for a longer duration favorable period. Could continue well into Feb. All weekly/monthly/seasonal guidance looks almost identical for Feb. Not perfect but magnitudes better than anything we've seen this year. Won't truly believe it until I'm shoveling though...

I like sticking to the 3 day rule meaning frozen precip starts within 72 hours or less. Some setups can get away with 4 day rule and this may be one of them if all 0z and 12z ops show frozen without degradation. We're walking a line with temps. Delay precip or miss the warm front WAA piece and it's a 100% rain storm

@psuhoffman if we aren't going to have a -ao/nao, the current d15 mean h5 across all ens is the next best thing imo. Feb 2015 was mostly northern stream. Most of 13/14 was northern stream except the Feb storm. Current look is like 2014/15 + southern stream. I can't really recall any winter in the past 15 years that had a similar hemispheric lw pattern

Lol. Only if you don't want any snow this weekend.

Keep this in mind going forward... After next weekend we look to enter a period of split flow. Ops will never ever ever be remotely close to accurate 10 days away with split flow regimes because the northern stream holds the keys and ops can barely get the NS right within 5 days. Stick to ens guidance only and even then it's just general ideas.