psuhoffman

agree the flow is very compressed to our northeast...so this will hit a brick wall somewhere...we need a health primary to the west so that the transfer ends up tucked nice and tight off the mid atlantic coast. Unfortunately that has us playing with temp issues. But the colder option has less upside.

the long range also is looking blah...not awful but we might have to wait for a reload of the pattern towards Mid February after this next 10 day stretch.

@Ji This captures the whole event without any contamination from other waves.... you really want this to trend any further north right now? Op runs will bounce around. Now I do want to see the EPS come north some...be more in line with the rest of guidance...but at this range we will still have some variance to operation runs...but we are a long way out to want it to start trending north already...we when are in the bullseye on the ensembles already and some of the ops.

It still gets some snow even north of the Mason Dixon line. Year the 1-2 feet stuff is in central to southeast VA...but even that run isn't where we need a HUGE north shift the last 100 hours. Where were the storms at 100 hours out when we missed south? Think back on all of those...the ones that teased us then went south...they were targeting NC... and we were being silly praying for a N trend of 250 miles. And a lot of those did trend north and affect southern VA but not enough to help us up here...think about our storms that were supposed to jack us 120 hours out...how often they still end up hitting PA instead. I would still rather be just north of the jack zone. Not by a ton...we dont want this to be so far south that we arent even in precip from 100 hours out. We dont want to need a 200 miles shift. But if we only need a slight north adjustment at 100 hours...that isnt bad. You really think this is going to absolutely NAIL the details from this range...and so where would you bet it shifts the final few days...a little north or a little south?

The upper low is more amplified but it tracks south...instead of tracking east from that spot at 114 it dives southeast...and that is why the southern solution.

yea its a fringe job... does get snow up into our area but the heavy is south of us.

Just compared and its way more amplified there then the GGEM and about in line with or maybe even slightly more amplified then the GFS.

It's hard to get h5 right and mess up the surface over and over. But...they score those things on a larger scale so if the UKMET has an issue with under and over amplifying discreet SWs it might not effect its overall score as much as it effects its ability to get details on a synoptic system correct.

I would think yea... guidance today has trended back towards a healthy wave coming across...that's what I wanted to see. Some of these runs are starting to align with my expectations for this setup. That GFS run might have been overkill but thats the kind of max potential we have if the upper low amplifies enough to our west.

It's hit or miss...sometimes its crazy amped. It had a few runs where it gave DC a blizzard before that costal scraper storm in 2018. And other times its way suppressed compared to other guidance...last winter it kept giving me 15" of snow from a storm that ended up way north long after all other guidance shifted.

Your really want to tempt fate with 120 hours left to go??? But isn't this a double edge sword...its partially the lack of cold press in front that allows the primary to amplify north and ends up with that bomb over southeast VA. The GGEM is colder but also a much less intense and "fun" storm...especially for us north of the DC area. I guess this is location specific...if I lived south of DC I probably don't want to chance "playing with that fire" and would take the less intense but more sure thing snow. Again..120 hours to go...we want to tempt the snow gods on this?

It would really really really suck...so this is not minimizing it...but sometimes I do think we overplay ice a wee bit...considering we survived like 2" of it in 1994 and yea it sucked but we made it. We are all here to tell the tale.

@leesburg 04 @H2O He is already at DCA for Thursday!!!

You know...its really frustrating when the long range tracking never pays off like lately...and then it makes the mid and short range tracking stressful because were so desperate to get snow that when things go wrong its gut wrenching. In a way the long range pattern tracking is less stressful. There is less pain run to run if a little detail goes one way or the other. Even this pattern...its gone EXACTLY the way I thought from weeks ago...but now some really subtle discreet details that you can't possibly see or worry about from 2 weeks away will determine if the foot of snow ends up being in PA or DC or Richmond. And now those details start to matter a lot and drive us crazy every run.

I suppose if I must... I can live with this solution

@stormtracker nevermind you can suffer a few hours of rain if it means we all get that ending HOLY P(*U#RPWIJASPOFJISA

Again...I think we are very possibly in the very very narrow "sweet spot" for this one. But this illustrates my point...we needed a north adjustment...but if you payed attention to the whole setup we really didnt have a lot of wiggle room with the thermal boundary to begin with. So we get a north adjustment and suddenly rain becomes an issue again. No margin for error either way. Luckly I think we might be in the razor thin "win" zone for this one. But damnit it can't keep being this difficult or we are rarely ever going to win.

I am soooo sorry...it was my last "double bind" post I did this.

I agree but I was pointing out that even though we need a "north" trend...we really barely have a cold enough profile to begin with. That's indicative of a larger scale issue then just this specific event.

Winchester was such a nice place...shame...real shame.

yea I actually have something REALLY important to do that day...and I have no problem driving in snow. I have driven through actual blizzards out west where I could only see 10 feet in front of the car. I have absolutely no issue with snow. But ICE....no thank you.

The 0z NAM is painful up here...I get almost no snow but 20 miles north of me gets 10" lol. Probably too much to ask to get that to start to shift south when the overall bleed is the other way the last 72 hours.

The secondary yes...but its ALL about the primary to our west...we need that to hold on longer...and this ICON run kills the primary a little quicker further south then the 12z run. That is the key because the flow becomes more compressed the further east you get. Once the storm transfers I expect absolutely no northward component and the precip will actually likely start to sink southeast from there. We need the primary to hold on and create that "inverted" trough feature to train moisture along from as the secondary forms. That inverted trough banking up against the compressed flow to the northeast creates a really strong focus for lift. That is the mechanism to get the precip NW. If the primary dies too soon the secondary will wrap up like that ICON run did to our south. Ideally we want to get the primary to hold on into WV or southern Ohio. Yes I know that sounds like blasphemy to some who equate a west track to rain...but once the transfer happens there is likely to be no further northward component to the precip shield so we need the primary to hold until AFTER we get the inverted trough up through our area and the heavy precip is overhead. Then it can make the jump. If it jumps to our south...we get that icon solution.

Before I say this let me preface that I am still optimistic for this storm. I think we are in a pretty good spot. I think this will work out. But I wanted to highlight the double bind we are in right now and why we keep failing despite what has been one of the better longwave patterns we have had in many years all winter long. Look at this from the 18z EPS. Now...that was a pretty good run...but we still need a north adjustment. The target was still just a little south of DC on that run. There were some nice hits but too many misses still. So we need a little more ridging or relaxing of the suppressive flow over the northeast to get the storm to trend north some...but look at where the "cold" boundary is as the storm approaches there! How much can we even afford to "give"? And yes the temps crash after once the storm secondary's and bombs to our southeast...but because of the suppressive flow to our north we need to get the primary up into southern Ohio or WV before it transfers to get heavy snow here. But what if that ridging does shift north say 50/100 miles? How much further before that primary maybe holds on into western PA and the transfer ends up to off NJ instead of off VA Beach and we get a miller b jump over us solution? And about 9 members of the 18z GEFS had just that. We're walking a razor edge on EVERY possible snow solution right now because of "THIS" double bind. Right there...on that run...we have barely enough suppression to prevent warmth from surging north of us ahead of the wave...but its slightly too much suppression for a storm to amplify enough to "crush" us. We have absolutely no margin of error because the cold is so freaking pathetic that to resist warmth from surging north of us ahead of any wave we need such a suppressive flow that it prevents any storms from amplifying. If the suppression relaxes we can get a storm but its rain. I debated not posting this... but I think we can keep this from becoming an out of control debate about "you know what". I am not going to even say its all "THAT". There are some factors that maybe aren't permanent. The PV got sent to the other side of the globe, the pac torched north america all fall and early winter and so perhaps the base state is even warmer now then just due to AGW. But regardless of all that...this is the bind we are in right now trying to get snow regardless of the pattern. The same exact equation is playing out Monday also. That storm is suppressed so much it becomes a strung out mess that barely gets heavy precip to the mason dixon line...and NYC is on the northern fringes. Yet DC can't get any snow??? If the storm was suppressed much more there would be no heavy precip anyways...this keeps playing out time and again all winter long.

Me too. Thing is...it is getting suppressed. NYC is on the northeast fringe! The real heavy precip stays south of PA. But even with the suppression the cold is too pathetic to hold. Here is the scary double bind that puts us in. If the thermal base state is so warm that to get cold we need more suppression then this...well look at Thursday. It’s not even that cold. It’s barely cold enough to snow really. And it’s taking such a suppressive flow to get even that, that there is a serious risk the storm gets squashed. So what’s our path to a win if the cold is so weak that to prevent warmth from surging north in front of any wave we need such a suppressive flow that nothing can amplify?