psuhoffman

I agree...probably. But if it isn't...it might be towel throw time

ya we're on the same path...unfortunately it sucks. 0 stars on yelp.

He is right but isn't this symbiotic also. The 850 low, just like the low at all levels, is impacted by the thermal profile/boundary. One reason the 850 low ends up so far north on the op GFS is also related to the fact the cold boundary is so far north. If the thermal profile was colder I doubt the 850 ends up way up there given that synoptic progression.

But for there to be WAA precip ahead of any wave there has to be some mid level southerly flow! That's normal. If the mid level flow was from the north we would be smoking cirrus lol. The problem is the airmass just isn't cold enough for the equation we need to work out. It's that simple. We can debate the "why isn't it cold enough" but all this attempt to find flaws that just aren't there is annoying. Look at all this SE flow.... and it was absolutely sheeting snow at my house in VA at this time. Know what the difference was...it was cold. The equation worked there because the air mass was cold enough that even with the WAA at the mid levels the profile of the column when mixed was cold enough to support snow. Anytime we have a wave approaching us from the west there is going to be a southerly flow at the mid levels...and there HAS TO BE or else we wont get precip! I am also going to poke at this interpretation but let me be clear your not wrong, we just have different points of view of the same thing. A different spin. But I am NOT saying you're wrong. However, to play devils advocate here...the point of the blocking is to influence the track of mid latitude waves in the way we want, specifically to get one to track just under us and to foster there being higher pressure over the top of it as this happens. We have that here! In the micro sense our flow is determined by those local features like the low and high on either side of us. The "blocking" and "50/50" features are irrelevant once the dominoes have been set in motion and the storm is tracking by us. Our local flow is dominated by that low near VA beach NOT some feature 1000 miles away. Those features did their job to get the storm to VA beach. Now in this case we don't have an NAO block. But we do have a Hudson High and we both have discussed how that is the next best thing to an NAO block...historically its been the next best way to get a snowstorm absent an NAO block because it simulates much of the same longwave impacts on the mid latitudes near us. I used 1996 above because it was a product of a Hudson High NOT NAO blocking. The NAO blocking in December was actually mostly a fail in our area, although NW of DC did get several small snows out of it. We got more snow in Feb from true blocking...but the 2 snowstorms in early Jan were from a very similar pattern to right now. Jan 2016 was also a very similar, maybe even more similar despite the opposite enso to this weeks pattern (which maybe isnt shocking since we're in more of a super nino look than a nina). But the Hudson block does do its job. There is a perfect banana high over the top on the 12z GFS. I really don't get the "high is racing out" takes. As the system is reaching our area the high is bananad over the top of it. Yea once the low is up off MD and NJ the high is long gone, but that is normal. The high is going to have to retreat by that point but it shouldnt matter because once we are on the west side of the low the northerly flow behind the low should save us. But of course that doesn't matter if the airmass is crap all around us...that northerly flow is just taking warm air from just northeast of us into our area. Look at January 2000, where the high is by the time the low is to our latitude. Its long gone. But it didn't matter. I guess I am just saying why do we need to drill down to these super specific reasons why everything wasnt the exact perfect everything we needed when the real issue is pretty obvious to me...its just not cold enough. In a grand sense the whole airmass over all of north america just might not be cold enough for what we need to make this work no matter the fact that its a pretty freaking awesome synoptic setup and progression that if it was simply colder would lead to a snowstorm. I am NOT saying we have to get into the elephant in the room. We can not discuss or debate WHY its too warm. I am not trying to bring that into here. I said my peace with that over in the futility thread this morning. But whether you think its a right now problem or not...to me the only real problem with this setup is the whole airmass just isnt cold enough. Frankly even on the permutations where the storm cuts inland its not the synoptic setup thats flawed its just so warm the storm is able to meander inland in search of a thermal boundary to ride along. Had the airmass had any freaking cold at all it would take a more canonical track even in those worse cutter looks IMO given the longwave setup.

Except snow NW is supposed to be common in a good but flawed progression with some snow here. This gave us that solution with a damn near perfect synoptic progression. @WxUSAF was just thinking looking at the snow distribution from the Gfs it looks a lot like the early Dec 1992 storm. But that storm was early Dec not the coldest week of the year and the synoptic progression of that was way way worse with a storm that initially cut way west then formed a secondary basically right over DC. This simulated the same result as we got from a severely flawed setup early Dec out of a nearly perfect progression in mid January. Yay.

At least it this run is right I can take the kids to WV next weekend instead of Nunavut. Maybe we can all meet up at Snowshoe or Deep Creek.

Ji is right. The high is actually in a perfect position. Banana over the top! The other map only showed the center of highest pressure giving the false impression the high was not ideal. Actually this is a great pressure representation. Can we please stop trying to find excuses. The thermal profile over N America is just so warm that it makes it REALLY difficult and even with a perfect High and low track it might still only end up a mostly rain event. What it did this run was at least mean some frozen to start and a snow event for the mountains. But even with a close to perfect synoptic progression it wasn’t enough to save us because the airmass is just so awful.

I made a huge rant in the futility thread this morning. I’m good.

Ok root for the full phase it is.

At this point I don’t care if it works out because Satans Arse pops out of the clouds in Nova Scotia and farts the cold air down to us.

MLK weekend I am taking the kids skiing somewhere and it has to be somewhere that has snow OTG also so they can play in it. At this rate I might be driving to Nunavut

It's Nora actually. My son is 8 now, and yea he likes to play in the snow but he is way more indifferent about it. But Nora's little heart is broken by the fact is hasn't snowed yet.

can we get the ICON antecedent airmass with the GFS track?

BTW one thing we should clear up...there is still a 50/50 low on the guidance. Its there...as the system we are watching is in the MS valley getting its act together there is a low over the 50/50 area just like we want...its just not the sub 500 monster polar vortex of doom some guidance was showing before from a convoluted polar jet phase phase with a mid lat system leading to a bomb cyclone. We shouldn't need all that.

Honestly if it wasn't for the fact my 4 year old loves snow and is asking me literally every day with a quivering lip "when's it gonna snow daddy" I probably wouldn't care at all anymore.

@Ji Don't worry we can track the next January peak climo perfect track rainstorm now

fixed

I see a repetitive problem we have here. To get it cold enough to our north we need a +AO or low pressure over canada pattern but we are too far south to get that cold to really help us in the zonal pattern that will invariably develop under that in the mid latitudes. But when we get the high latitude pattern we need to cause the jet to buckle to out south our source region temps are torched. High latitude blocking was always associated with warm anomalies to our north. But those warm anomalies were still cold enough to snow here. But now that when we have upper level high pressure over Canada it completely torches our source regions to the point its no longer workable.

Last January we had an Aleutian trough with an AK ridge and cross polar flow. But the reason it didn't end up snowier in a more widespread sense ( some localized parts of our area got lucky but it wasn't a snowy season on a larger scale) was what is a common problem with cross polar flow...we didn't have any help on the atlantic side. As I've said a cross polar flow pattern is 1 rare and 2 not even the best pattern for us to get reliable snow. Last January was a rare example of cross polar flow...and not all of the area even got that much out of it. So it was a fairly rare thing (one cold month surrounded by warmth) and it wasn't even that affective at giving us a lot of snow, so not sure why that should make me feel that much better. OH...and it wasn't even THAT cold considering the pattern frankly

PPS... we will still get seasons where the predominant pattern includes both an AK ridge AND an eastern trough so that we get constant injections of cross polar air and snowy years because of it. But those are incredibly rare things and so this is about what our fate is during the majority of the time when that is not the case. And even in those in between years it will still snow some...it's not like we are seeing no snow at all the last 7 years. Last year we got some incredibly unlikely luck with some wave spacing in early Jan and for coastal areas a perfectly timed phase in late January to get snow so I am not saying it won't ever snow...just that it seems to be taking an increasingly unlikely confluence of events to make it happen.

PS: I just feel like the micro excuses are wearing out at this point. Its been a string of overly specific reasons/excuses why a pretty good synoptic setup failed. "December climo sucks", the pacific was bad, no HL blocking, the WAR...but what they all have in common is no cold air. And frankly we've failed with exact opposite pacific patterns recently so I am tired of the "its the pacific" excuse. The pacific is always going to be there upstream of us so if we can't snow because the pacific is too warm thats never going away.

I had wanted to try to avoid this general topic completely but its become obvious that is impossible...but I will keep my part of this discussion to this thread so as not to annoy those that would rather not think about this in the main thread. @Terpeast I see this as all related. A lot of this is just conjecture at this time simply because we don't yet have a long enough period of data to prove with statistical significance but some very bright minds along with well designed simulations have theorized that there is a causality between AGW and several of these chronic pacific issues we have been having for a majority of our winter seasons recently from the expansion of the Hadley Cell to some of the persistent SST issues in the tropical Indian and Pacific, to the prevalence of a la nina base state. Then, add in that on top of the longwave pattern issues created by these problems in the Pac, regardless of that at any given moment in time warm anomalies over the NH land masses are outnumbering cold about 70-30. So even without those issues simply by pure chance our odds of having cold over us are going to be more difficult. And lastly...there is conjecture that the SST changes also related to warming in the Atlantic are partly aiding the prevalence of the WAR (which is also a feedback issue from the pac longwave pattern as well!) and why its been difficult to get or sustain a 50/50 feature. Basically, there are a lot of interrelated factors caused by warming, but every single one of them seems to be the opposite of what we would want. The only factor related to warming that could work in our favor is the increase in precipitation patterns during the cold season in general. And I do think we have seen evidence of this in the rare cases where we get a cold season but that benefit only matters when its cold which is becoming increasingly rare. @CAPE and @WxUSAF both of your analysis of the issues regarding the specific details we need (50/50 or perfect phasing) are 100% accurate. My point is just, at some point it feels hopeless if we need some super anomalous string of events to go exactly perfectly to get snow as if we are living in coastal SC or something. My point the last few days when I voiced my concern with this setup has been the snow solutions seemed to be relying on something I don't see as very likely and even if it did happen is certainly not something we can expect to become a reliable repetitive way to get snow. Needing some mid latitude system to phase and bomb into a super cyclone and lead to the inception of a TPV in exactly the perfect location at exactly the perfect time is not the way I want to have to roll here. Yes a 50/50 is a feature in just about every one of our 20" snowstorms. Because to get a storm that big in the DC/Balt area we need some pretty major resistance to the WAA necessary. We are too far south to be obliterated by a CCB like NYC north...the only way we get a HECS here is if a majority of that snow comes from a strong WAA feed ahead of the wave and for that to stay all snow and produce prolific totals we need a 50/50. But I am not lamenting that this isn't going to be a 20" storm. What happened to getting a 6" snow from a messy storm where the mountains and get 20" from a setup like this. When I examined every 4"+ snow at BWI years ago that made up a lot of our events. Frankly very very very few of our storms were because we lucked into the absolutely perfect conditions, and when that happened thats when we got those 20" storms. But most of the snow events were messy. What happened to getting 3" at DCA and 5" at BWI and 6" at IAD from a messy storm where we mix but the big snow is to our NW. That used to be the typical outcome of a system that tracked to our south but everything wasn't "perfect". Lately it seems we need perfect to get any snow. Basically...the storms like these below... Hi Low QPF Snowfall 36-30 1.13 4.6 37-30 .77 4.1 45-33 .86 6.9 34-31 .92 3.0 37-33 .92 3.4 39-32 .72 3.0 43-33 1.09 5.5 39-31 1.04 6.9 39-32 .67 3.4 33-30 1.63 6.4 38-33 1.03 3.3 I pulled all of these were from DCA from my past snowfall study. Look at the temps and precip...these were all obviously mix storms...and I remember the H5 from most of these it was because there was no 50/50 and a marginal "pac puke" as we call it lately, airmass to work with...but they were good tracks during mid winter and so we at least got some snow from them. And my area did great from all these storms. I think they were all 12" plus up here. But now...look at many of the permutations in the 3 ensembles. They have perfect track systems with rain to Montreal! Another good example is 1998. I bring that up because that year is showing up in current analogs a lot. And yea that year SUCKED for DC snow so its easy to say "well this happened before". But I was at Penn State that year and we got crushed with snowstorm after snowstorm all winter. Even my area here had about 20" that season because all those perfect track rainstorms in DC were a messy mix with a few inches of snow up here. Places with elevation to the NW of the cities actually got quite a bit of snow that winter. But most of the permutations of this are rain even in those places with a perfect track, and we've had several of these over the last few years. That is my bigger concern. We can't seem to get any frozen event, even a flawed mixed type, unless everything is perfect or some incredibly unlikely string of dominoes all fall exactly the right way. And lastly, yea the pac is the problem. But guess what the PAC is what is upstream from us, its HUGE, its the largest heat source on the planet, and other than the rare times when there is cross polar flow (and that isn't even really a good longwave pattern to get a system under us!) we will be dealing with an airmass that has significant influence from the PAC. The airmass this week isn't pure tropical pac puke. There is quite a mix of flow from the Yukon area mixed in with mid latitude pacific air. The problem is its torching even in the Yukon, and the mid latitude pac air is +5 to +10 also! And both of those facts don't seem to be a right now at this moment bad luck kinda of problem. They seem to be a permanent base state status quo lately. @Weather Will I am not giving up, there is still a path to get snow here. The phased bomb 50/50 scenario could come back. Or Wxusaf's scenario of a perfect phase could happen. But what is depressing to me is how difficult that is and how that is never going to be a reliable way for us to get snow. Look at the ensembles. They are very good simulations based on the current conditions. They are realistic possible permutations. And the vast majority of the permutations show a rain solution even with a perfect track and even in places to our NW. Even if we get lucky and we get some super bomb to cause a TPV to form exactly where we need it and this ends up snow...that doesn't change the fact that it was a realistic scenario that a storm could take an absolutely perfect track on what is statistically the coldest week of the year in DC, and it would be nothing but rain all the way to Canada! That is alarming in a larger 30k foot view kinda way to me. I am not focused on the specifics of this event, that is a bigger problem imo.

I don’t see much blue anywhere over any mid latitude land masses.

Perfect write up but let me summarize this…. On the coldest week of the year it’s simply too warm no matter how a storm tracks and there is no cold air within 1000 miles of us.