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The March Long Range Discussion Thread, Winter's Last Stand


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3 minutes ago, nj2va said:

Today reminded me again why I’m ready for sustained warmth. Y’all crazy for wanting more cold. 

But how cool would a 2' March paste finale before summer of sustained upper 90s and high humidity be? Cmon you know you wouldnt kick the control run out of bed if that was a 12 hr prog staring you in the face.

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2 hours ago, C.A.P.E. said:

Probs see it in May and June, real time and verified.

You wouldn't miss it much if you went back and looked at just about every GEFS run for Jan and Feb. Lol another classic LR fail.

I will never put as much faith, or belief, in seasonal models again after this winter total concensus failure !! :thumbsdown:  Nor will I weigh the opinion from long range forecasters as seriously after this season. 

Might use the tool of the past , the cirrus clouds and the lowering sky.  You know as I age I tend to miss the days of long ago when snowstorms came into view from a few days away.  I enjoy the weather, the extremes and tracking, but honestly maybe next  winter I go 72 hours without looking at a model and even listening to a forecast. I like to be surprised once more before I die. :)   

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45 minutes ago, nj2va said:

Today reminded me again why I’m ready for sustained warmth. Y’all crazy for wanting more cold. 

I didn't have to wear my ski cap hat today.  :shiver:  I lose a lot of body heat from my lack of hair, LOL ....... and getting a short,  1.5 cut does not help either.   

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3 hours ago, BaltimoreWxGuy said:

Euro has a monster storm for next week but it’s well off the coast. Would be a hell of a storm for ships to try to move through though 

Plenty of time for the trough to sharpen up and draw it back inland. :D 

 

Eta: Actually wonder if that’s possible. The storm is there on the GFS twins too. We need some @showmethesnow @psuhoffman or @Bob Chillthoughts. 

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11 hours ago, 87storms said:

i've thought about this sun angle thing a bit.  my conclusion is that it affects ratios more than it does stickage.  a 32 and below surface is 32 and below, but i've definitely noticed that some of these march snowers have generally worse ratios (and possibly higher rate of melting after stickage as well), during the day.  i could be wrong and having a selective memory here, but it would make sense that the sun angle would impact a snowflake's rate of melting on the way down.  yes, we are capable of march powder, but i think fringe temps are more of a problem in march than january.  rates would overcome that for obvious reasons.  how much of an impact is up for the debate, but i think it's kind of irrational to say it makes no difference. 

IR (infrared rays) has very little to no direct impact on the snowflakes rate of melting as it travels to the ground. In other words it isn't like the IR is internally nuking the snow flakes causing them to melt. To understand how much IR is being absorbed by an object all you need to do is look at the color of an object. White, such as a snowflake, basically means most of the IR is not being absorbed and is instead being reflected back and/or scattered. So there is very, very little warming of the snowflake itself even with an increase of the IR. Dark objects on the other hand are indicative of objects that are absorbing IR and the darker the more that is being absorbed. If you have run barefoot across blacktop to get to that patch of cool grass shows this concept well. 

But indirectly the increase in IR does have an impact on the environment surrounding the snowflake as it introduces more potential energy/heat into the equation. And the environment itself is what determines how the snowflake forms (ratios) and the rate of meltage as it travels to the ground. So take an equivalent storm in January but double? the IR seen in March and it will have an impact on the temp profile of the column (warmer) especially at cloud level where the snow is being formed and directly off the surface. This is because the condensed water vapor in the clouds will absorb some of the IR as well as the surface that has an high absorption rate. The atmosphere between the cloud deck and the surface on the other hand will see minimal warming directly from IR and will instead be influenced by the warming seen above and below as air parcels move upwards and downwards through this region (mixing). Now this brings up another aspect of what we see with the IR as it streams through the atmosphere. The thicker and deeper the cloud deck the less IR is allowed to reach the surface. This means we see greater warming upstairs then we see downstairs. Conversely less clouds and the greater warming is seen on the surface. 

Now barring a very marginal lead in of temps in the upper levels (850-700 mb), where increased heating from IR of a couple/few degrees can tip the balance, we typically want to see the greater warming occurring upstairs vs. downstairs. This is because the lower level temps warm much quicker to the seasonal changes then the upper which lag a good deal behind. So the limiting factor on these late season storms is most often the lower levels just off the surface where temps will more then likely be very marginal to begin with without adding even more heat to it from IR vs. the upper where temps will typically be much colder with a greater margin to support warming. So it is not unusual to see high ratio (12-1, 15-1, etc...) snow formed in the upper levels only to see low ratios (6-1, 7-1, or even worse a snow/rain mix or even just rain) for ground truth as the snow falls through the much warmer lower levels and melts.

Now minus an anomalously cold air mass what we need to see for our snow chances late in the season is a rapidly deepening low in our general local which not only limits the amount of surface IR warming due to thicker cloud cover but also helps to mix out any warm layers through its greater dynamics. Now I know some will point out that the 850's sometimes will not support snow on some of these model depictions of storms hence this is the limiting factor on our snow chances. But most often times that is not the case and the limiting factor will end up being the lower levels just off the surface after all. As I mentioned before the lower levels warm quicker then the upper during the seasonal changes thus quite often the 850s will be marginal on any lead in to a storm. But this late in the season where you really need to be looking is directly above that level at either a sounding or the 700 mb map. Quite often you will see the temps are much colder at these levels as they still haven't responded to the seasonal change. So what we see with a deepening storm is temps will rapidly lower in the upper levels (supporting snow) and progress downward through the lower levels as mixing of the atmosphere occurs. So the lower levels just off the surface are indeed the limiting factor in most cases as they take the longest to cool down and the less IR heating thrown into the equation the better as we see less melting of the snow as it travels downward and much less melting occur directly on the surface which can be greatly affected by IR warming.

Best case scenario for any late season storm is to see the 500's close off and go for the capture of any developing storm just to our east. Typically when we see this the other levels of the atmosphere (925, 850, 700 mb) respond as well where we see either a trough/closed low within these levels as well in what is called a stacking low. What this brings is much colder temps in the upper levels (850-500 mbs) as well a much better ability to mix those temps downwards and quicker as the low bombs. We also typically see high ratio snows formed in these bombing storms as we see very good lift through the snow making regions. These ratios can be substantially reduced though as the snow travels through the lower/ warmer levels. Now a bombing storm can be seen if you look at yesterdays EPS control run. And though I don't have access to the different atmospheric levels I would still put good money on this scenario playing out just by looking at how the surface responds. Now the snow maps of the control run were impressive but consider this. On the northern portion, where the best CBB banding occurs we are probably talking 12-1 ratios (ground truth) at the very least as the surface temps would have very little impact. Sadly it is more then likely just a fantasy run otherwise we would be talking an HEC through the mid-Atlantic into the NE.

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25 minutes ago, Scraff said:

Plenty of time for the trough to sharpen up and draw it back inland. :D 

 

Eta: Actually wonder if that’s possible. The storm is there on the GFS twins too. We need some @showmethesnow @psuhoffman or @Bob Chillthoughts. 

Pretty much in wait in see mode at this point. All the models have been back and forth with the placement/axis/evolution/timing of drop of the trough in the east through that time period. The setup itself shows a good deal of promise (potential high impact storm) but right now on the latest runs I would say the trough is too progressive for our tastes and argues for an OTS solution. But with the amount of play we are seeing with that feature run to run the outcome is still very much up in the air IMO.

eta: I will say that even if we see coastal impacts that doesn't guarantee that it would be snow. Temps will be marginal and we will need to see a fairly rapidly developing system as it runs to the east of our region. Otherwise we will not see the rates and mixing needed to overcome the lower level warmth.

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Yes still a wide range of solutions over a 3-4 day window with various models  

tracking "our" storm through central Florida before going out to sea (e.g. GFS), 

giving us a glancing blow (CMC),

snowing on Mt. Mitchell hikers (FV3-GFS)

sending wind, snow, and/or rain to Halifax (Euro). 

 

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The "type" of synoptic setup we see has worked before... an initial system in the midwest along with associated upper level trough digging and combining with a southern stream system off the southeast to produce a coastal storm.  There have been several examples of March storms like that, 1958 was one, Feb 58 worked that way also.  BUT...for every time that setup worked there were 99 that didn't.  And almost all the examples that did work were associated with some high latitude blocking and we have none right now.  So I am skeptical.  Doesn't mean it cannot happen, there are exceptions to every rule and March can be really fluky, but I think the pattern looks too progressive for me to believe the monster bomb solutions on a minority of the guidance right now.  The more progressive and "less fun" solutions look more realistic.  

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5 minutes ago, psuhoffman said:

The more progressive and "less fun" solutions look more realistic.  

That has been the hallmark of this winter from the beginning.  No slowing down the Pac jet, no blocking , no -NAO and no +PNA.  and

a pathetic + AO  ( Judah :thumbsdown: )   

Everything we need in one fom or another, even in combination,  never got going. (  except for maybe I say 5 % of the time )   

If I saw a deep -NAO and some other signals I maybe say this had a chance,  but no way we get any snow from this system. Like you said , for every one that has worked for us in this setup 99 others have failed. 

 

   

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48 minutes ago, frd said:

That has been the hallmark of this winter from the beginning.  No slowing down the Pac jet, no blocking , no -NAO and no +PNA.  and

a pathetic + AO  ( Judah :thumbsdown: )   

Everything we need in one fom or another, even in combination,  never got going. (  except for maybe I say 5 % of the time )   

If I saw a deep -NAO and some other signals I maybe say this had a chance,  but no way we get any snow from this system. Like you said , for every one that has worked for us in this setup 99 others have failed. 

 

   

We actually have 2/3 coming up.  The pac jet is buckling and the PNA is in a good spot the problem is the atlantic side is just god awful and way too progressive.  There were LOTS of times this winter where the atlantic side was "OK" and with this pacific it would have worked.  Thing's just don't want to time up.  

Setup1.thumb.png.cdd550825e3bad5efcb65e73b389b210.png

That ridge axis out west is good, split flow with stj system cutting under.. but look how progressive the flow is in the atlantic.  There is nothing to buckle the flow and allow major amplification.  

setup2.thumb.png.b03ebc6f4b9e777376ea149530d8901c.png

STJ system has reached the east coast and a ridge west of Hudson Bay isn't a bad thing but the northern stream is just flying by to the north and is likely to shunt it off the coast instead of phasing and amplifying the trough in the east.  

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21 hours ago, das said:

Some of the experimental work to assess the impact of MJO on tangible North American weather is yielding interesting results.  For example, typically, Phase 8 of the MJO is typically cold in the east DJF but, when the experimental Multivariate PNA (MVP) is negative, it actually trends warm.  MVP is assessing OLR as a decent proxy for tropical convection in the MJO domains as well as streamwaves at 850 and 200 hPA in near real time .  If you look at the MVP plot for the last 90 days, you can see it has indeed been negative during the time period we expected the best outcomes according to the ENSO and MJO forecasts.  

849375815_90DayMVP.thumb.jpg.83e7083c75fd65c104d80c5e2714e5f5.jpg

 

If y'all want to dig into MVP a bit, here's some decent reading.  

Peer-reviewed, evidenced-based paper:

mwr-d-13-00118.1.pdf

White paper inject for NWS staff:

https://www.nws.noaa.gov/ost/climate/STIP/37CDPW/37cdpw-cschreck.pdf

Easy-to-digest slide deck from the researchers:

https://slideplayer.com/slide/13103907/

Link to real-time Multivariate PNA outputs:

https://ncics.org/portfolio/monitor/mjo/extratropics/

BTW, click around that site if you are interested in tropical forcing outputs.  There's an absolute treasure trove of MJO & tropical forcing data there.

Thanks, excellent stuff... Question.  Are they working on a way to turn the MVP into a predictive tool?  

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12 hours ago, Ralph Wiggum said:

But how cool would a 2' March paste finale before summer of sustained upper 90s and high humidity be? Cmon you know you wouldnt kick the control run out of bed if that was a 12 hr prog staring you in the face.

Unfortunately in reality we'll be left with a weak enough trough in the east to give us 43 and 2" of rain.  No thanks.

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1 hour ago, smokeybandit said:

Heavy snow or nothing at all.  My pond (where there's not supposed to be a pond) in my back yard keeps getting bigger, and would rather not have the county come try to say I have waterfront property and up my taxes.

Been crazy to see the amount of standing water in fields and around people's houses as I have been out. Mosquitoes are going to be insanely obnoxious this year! 

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a hecs in march sounds good on paper, but i really have no interest in seeing mounds of snow through april nor do i have any interest in basketball courts and bike trails being covered/muddy in spring.  that's for the birds.

i'll take a moderate event though.

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3 hours ago, showmethesnow said:

IR (infrared rays) has very little to no direct impact on the snowflakes rate of melting as it travels to the ground. In other words it isn't like the IR is internally nuking the snow flakes causing them to melt. To understand how much IR is being absorbed by an object all you need to do is look at the color of an object. White, such as a snowflake, basically means most of the IR is not being absorbed and is instead being reflected back and/or scattered. So there is very, very little warming of the snowflake itself even with an increase of the IR. Dark objects on the other hand are indicative of objects that are absorbing IR and the darker the more that is being absorbed. If you have run barefoot across blacktop to get to that patch of cool grass shows this concept well. 

But indirectly the increase in IR does have an impact on the environment surrounding the snowflake as it introduces more potential energy/heat into the equation. And the environment itself is what determines how the snowflake forms (ratios) and the rate of meltage as it travels to the ground. So take an equivalent storm in January but double? the IR seen in March and it will have an impact on the temp profile of the column (warmer) especially at cloud level where the snow is being formed and directly off the surface. This is because the condensed water vapor in the clouds will absorb some of the IR as well as the surface that has an high absorption rate. The atmosphere between the cloud deck and the surface on the other hand will see minimal warming directly from IR and will instead be influenced by the warming seen above and below as air parcels move upwards and downwards through this region (mixing). Now this brings up another aspect of what we see with the IR as it streams through the atmosphere. The thicker and deeper the cloud deck the less IR is allowed to reach the surface. This means we see greater warming upstairs then we see downstairs. Conversely less clouds and the greater warming is seen on the surface. 

Now barring a very marginal lead in of temps in the upper levels (850-700 mb), where increased heating from IR of a couple/few degrees can tip the balance, we typically want to see the greater warming occurring upstairs vs. downstairs. This is because the lower level temps warm much quicker to the seasonal changes then the upper which lag a good deal behind. So the limiting factor on these late season storms is most often the lower levels just off the surface where temps will more then likely be very marginal to begin with without adding even more heat to it from IR vs. the upper where temps will typically be much colder with a greater margin to support warming. So it is not unusual to see high ratio (12-1, 15-1, etc...) snow formed in the upper levels only to see low ratios (6-1, 7-1, or even worse a snow/rain mix or even just rain) for ground truth as the snow falls through the much warmer lower levels and melts.

Now minus an anomalously cold air mass what we need to see for our snow chances late in the season is a rapidly deepening low in our general local which not only limits the amount of surface IR warming due to thicker cloud cover but also helps to mix out any warm layers through its greater dynamics. Now I know some will point out that the 850's sometimes will not support snow on some of these model depictions of storms hence this is the limiting factor on our snow chances. But most often times that is not the case and the limiting factor will end up being the lower levels just off the surface after all. As I mentioned before the lower levels warm quicker then the upper during the seasonal changes thus quite often the 850s will be marginal on any lead in to a storm. But this late in the season where you really need to be looking is directly above that level at either a sounding or the 700 mb map. Quite often you will see the temps are much colder at these levels as they still haven't responded to the seasonal change. So what we see with a deepening storm is temps will rapidly lower in the upper levels (supporting snow) and progress downward through the lower levels as mixing of the atmosphere occurs. So the lower levels just off the surface are indeed the limiting factor in most cases as they take the longest to cool down and the less IR heating thrown into the equation the better as we see less melting of the snow as it travels downward and much less melting occur directly on the surface which can be greatly affected by IR warming.

Best case scenario for any late season storm is to see the 500's close off and go for the capture of any developing storm just to our east. Typically when we see this the other levels of the atmosphere (925, 850, 700 mb) respond as well where we see either a trough/closed low within these levels as well in what is called a stacking low. What this brings is much colder temps in the upper levels (850-500 mbs) as well a much better ability to mix those temps downwards and quicker as the low bombs. We also typically see high ratio snows formed in these bombing storms as we see very good lift through the snow making regions. These ratios can be substantially reduced though as the snow travels through the lower/ warmer levels. Now a bombing storm can be seen if you look at yesterdays EPS control run. And though I don't have access to the different atmospheric levels I would still put good money on this scenario playing out just by looking at how the surface responds. Now the snow maps of the control run were impressive but consider this. On the northern portion, where the best CBB banding occurs we are probably talking 12-1 ratios (ground truth) at the very least as the surface temps would have very little impact. Sadly it is more then likely just a fantasy run otherwise we would be talking an HEC through the mid-Atlantic into the NE.

good stuff.  it makes sense (well, as much as it can to someone who only took 3 semesters of college physics lol).  i agree that the 500 chart plays a huge role here, at least from experience.  i feel like this year we've been lacking with good tracks...for the most part.  just not enough cold in general, which makes it even more complicated in march.

long story short, it seems like sun angle would affect the overall environment, but if it's cold it's cold...as psu said before, if it's cloudy there won't be as much of an effect anyway.  the problem is that it's just flat out warmer in march (sun angle)...therefore, generally less chances.

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59 minutes ago, 87storms said:

a hecs in march sounds good on paper, but i really have no interest in seeing mounds of snow through april nor do i have any interest in basketball courts and bike trails being covered/muddy in spring.  that's for the birds.

i'll take a moderate event though.

You're not one of us :O

Show yourself the door. :hug:

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4 minutes ago, losetoa6 said:

Interesting Gfs run at 192....gulf energy trying to phase in with some upper midwest energy ...most likely too late but h5 isnt terribly far off from something. 

Looks like all models at 12z have a major storm off the coast. Just too far east for now.

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2 hours ago, psuhoffman said:

Thanks, excellent stuff... Question.  Are they working on a way to turn the MVP into a predictive tool?  

Reanalysis is a part of the program so, yes.  Next steps are to:  "determine why some MJO events produce a response over North America while others do not. Preliminary results suggest that the convective anomaly near Hawaii might play an important role. This convection may be associated with anti-cyclonic wave breaking from the extratropics. Therefore, further research is required to determine whether the convection is driving the circulation or vice versa".  So, still in the research domain but, there is very little meteorological research being done just for the sake of research anymore.  The vast majority of it is focused on expressly enhancing predictive capabilities and mitigating impacts.  

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6 hours ago, showmethesnow said:

IR (infrared rays) has very little to no direct impact on the snowflakes rate of melting as it travels to the ground.

most often times that is not the case and the limiting factor will end up being the lower levels just off the surface after all.

Great writeup. This graphic supports your contention that it's really not the sun angle melting the snow while it is forming or ground temps preventing accumulation as much as increased warmth in the lower levels that reduces our snow chances in March. Note how much snow falls in March in areas at the same or even LOWER latitude than we are. The difference is elevation, which tends to offset the lower level warmth issues. 

image.thumb.png.040f15004f96bde9547f3c5db5711aa6.png

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