March med-long range disco 3

[osfan24]

Euro ensemble is ridiculous. 14-18 inches at 10:1 ratio across the region. Seems super bullish. Some individual members are pretty impressive. A couple approach 2 feet. 4 are pretty much complete misses, especially for Baltimore and south.

[psuhoffman]

 

06Z GEFS has a very similar solution to the overnight EPS. Delays the northern part of the trough/energy and develops a distinct wave on the southern portion of it riding up the trough. Would suggest a southern dominant low.

I see the changes as positive.   The phasing thing is over simplified. The streams are still interacting just differently. Phasing isn't all or nothing. But instead of a clean transfer between the northern and southern branch and a quick consolidation into one h5 center the stj system is dominant and slingshots up the coast as the northern stream upper energy dives in and swings behind then under it. At that point they do merge into one system. That evo might limit our top end potential a bit because the stj system will be racing north and the disconnect means no wrap around. Maybe with luck some convective snows with the upper low but it's never as good as if their phases up and the upper low has a connection to the moisture inflow.  But if we want a 6-12" (maybe a bit more) thump of heavy snow this is the cleanest easiest way to do it. Less risk of bust. Not no risk but less. 

If we want to go for broke the way this becomes a hecs is now that the southern system is the dominant one if we did trend towards a phase where the northern stream transfers its energy into that system as it bombs off the Carolinas and they come north as a fully consolidated system instead of doing that weird fujiwara thing were talking epic. 

[mappy]

 

Yes. I think so . gfs is really close to snow ... sleet.. drizzle and dryslot... but it is still a big hit.  euro has a great track... little further east of the gfs..  with lots of ensemble support 

 

 

If I were you I would root for the gfs.. where you are.. you would probably get a foot of heavy wet snow

Thanks! I'll check out soundings now that I'm at work and can sit and check things out. 

[EB89]

Anyone have the Panasonic from last night?  If not does anyone have the euro qpf output for KFDK? TIA

[mappy]

 

Anyone have the Panasonic from last night?  If not does anyone have the euro qpf output for KFDK? TIA

subtract .3 (precip from today)

[mappy]

06z GFS Cobb

[mappy]

can't edit that post for some reason -- that's for Westminster. 

[osfan24]

 

I see the changes as positive.   The phasing thing is over simplified. The streams are still interacting just differently. Phasing isn't all or nothing. But instead of a clean transfer between the northern and southern branch and a quick consolidation into one h5 center the stj system is dominant and slingshots up the coast as the northern stream upper energy dives in and swings behind then under it. At that point they do merge into one system. That evo might limit our top end potential a bit because the stj system will be racing north and the disconnect means no wrap around. Maybe with luck some convective snows with the upper low but it's never as good as if their phases up and the upper low has a connection to the moisture inflow.  But if we want a 6-12" (maybe a bit more) thump of heavy snow this is the cleanest easiest way to do it. Less risk of bust. Not no risk but less. 

If we want to go for broke the way this becomes a hecs is now that the southern system is the dominant one if we did trend towards a phase where the northern stream transfers its energy into that system as it bombs off the Carolinas and they come north as a fully consolidated system instead of doing that weird fujiwara thing were talking epic. 

Definitely some good points. I say we just go for broke, despite the complications. We seem to be trending toward the southern system becoming dominant, so that piece is there. Getting the transfer as it bombs off the Carolinas is the part that seems like a huge stretch at this point, but maybe I'm missing something.

[PDIII]

 

can't edit that post for some reason -- that's for Westminster. 

Can you do the 0z?  I think that one was more fun.

[EB89]

 

subtract .3 (precip from today)

Thank you. It is appreciated. So it gives Frederick around an inch. So it would look to be between 10-14 with ratios factored in?

[mappy]

 

Can you do the 0z?  I think that one was more fun.

sure. again for westminster

[dallen7908]

06UT GFS DCA (take a gander at the temporal volatility in the snow ratios!) 
170314/0000Z  90  09013KT  31.0F  SNOW    4:1| 0.1|| 0.00|| 0.00|| 0.036    4:1|  0.1|| 0.00|| 0.00|| 0.04  100|  0|  0
170314/0300Z  93  07011KT  30.1F  SNOW   21:1| 7.2|| 0.00|| 0.00|| 0.341   19:1|  7.3|| 0.00|| 0.00|| 0.38  100|  0|  0
170314/0600Z  96  04015KT  30.3F  SNOW    8:1| 3.2|| 0.00|| 0.00|| 0.400   14:1| 10.5|| 0.00|| 0.00|| 0.78  100|  0|  0
----------------------------------------------+----++-----+-------------++--------------++-------------++-----------+---+---
170314/0900Z  99  03017KT  31.2F  SNPL    1:1| 0.2|| 0.23|| 0.00|| 0.173   11:1| 10.7|| 0.23|| 0.00|| 0.95   35| 65|  0
170314/1200Z 102  34014KT  31.7F  SNOW    9:1| 0.6|| 0.00|| 0.00|| 0.066   11:1| 11.3|| 0.23|| 0.00|| 1.02  100|  0|  0
170314/1500Z 105  32012KT  31.9F          0:1| 0.0|| 0.00|| 0.00|| 0.000   11:1| 11.3|| 0.23|| 0.00|| 1.02    0|  0|  0
170314/1800Z 108  31005KT  32.8F          0:1| 0.0|| 0.00|| 0.00|| 0.000   11:1| 11.3|| 0.23|| 0.00|| 1.02    0|  0|  0
----------------------------------------------+----++-----+-------------++--------------++-------------++-----------+---+---
170314/2100Z 111  VRB01KT  32.4F  RASN    0:1| 0.0|| 0.00|| 0.00|| 0.010   11:1| 11.3|| 0.23|| 0.00|| 1.03   71|  0| 29
170315/0000Z 114  VRB00KT  30.1F  SNOW   23:1| 0.6|| 0.00|| 0.00|| 0.028   11:1| 12.0|| 0.23|| 0.00|| 1.05  100|  0|  0
170315/0300Z 117  27007KT  27.9F          0:1| 0.0|| 0.00|| 0.00|| 0.000   11:1| 12.0|| 0.23|| 0.00|| 1.05    0|  0|  0
170315/0600Z 120  32011KT  26.7F  SNOW   14:1| 0.5|| 0.00|| 0.00|| 0.036   12:1| 12.5|| 0.23|| 0.00|| 1.09  100|  0|  0
----------------------------------------------+----++-----+-------------++--------------++-------------++-----------+---+---
170315/0900Z 123  31014KT  22.0F  SNOW   10:1| 0.1|| 0.00|| 0.00|| 0.009   12:1| 12.6|| 0.23|| 0.00|| 1.10  100|  0|  0

[mappy]

 

Thank you. It is appreciated. So it gives Frederick around an inch. So it would look to be between 10-14 with ratios factored in?

10:1 snow map has 14" for Frederick. Subtract 2" for today. 

[mappy]

^^ sorry -- 12" for Frederick on total snow map

[EB89]

 

^^ sorry -- 12" for Frederick on total snow map

Thanks again. I generally just hide in the background here, but I do have questions every now and then.

[mappy]

 

Thanks again. I generally just hide in the background here, but I do have questions every now and then.

Happy to help! 

[showmethesnow]

 

I see the changes as positive.   The phasing thing is over simplified. The streams are still interacting just differently. Phasing isn't all or nothing. But instead of a clean transfer between the northern and southern branch and a quick consolidation into one h5 center the stj system is dominant and slingshots up the coast as the northern stream upper energy dives in and swings behind then under it. At that point they do merge into one system. That evo might limit our top end potential a bit because the stj system will be racing north and the disconnect means no wrap around. Maybe with luck some convective snows with the upper low but it's never as good as if their phases up and the upper low has a connection to the moisture inflow.  But if we want a 6-12" (maybe a bit more) thump of heavy snow this is the cleanest easiest way to do it. Less risk of bust. Not no risk but less. 

If we want to go for broke the way this becomes a hecs is now that the southern system is the dominant one if we did trend towards a phase where the northern stream transfers its energy into that system as it bombs off the Carolinas and they come north as a fully consolidated system instead of doing that weird fujiwara thing were talking epic. 

I agree, I view the changes as positive as well. My previous comments as far as not phasing were in the general thoughts of in the south that would benefit of our region. Later on we do see the interaction of streams but that would be of more consequence for north of us.

Funny you mentioned the bolded above. That was the first thing that entered my mind when I saw the initial setup with just a little adjustment. Adjust that northern portion of the trough to a compromise of both the 12z and the 00z on speed and have that trough drop somewhat deeper and things could become very interesting. But at this point I would be happy with the solution being show which would be a big dog for March which would most likely result in snowfalls of close to a foot or more for those who fall a little north of the rain/snow line.

[SomeguyfromTakomaPark]

 

I agree, I view the changes as positive as well. My previous comments as far as not phasing were in the general thoughts of in the south that would benefit of our region. Later on we do see the interaction of streams but that would be of more consequence for north of us.

Funny you mentioned the bolded above. That was the first thing that entered my mind when I saw the initial setup with just a little adjustment. Adjust that northern portion of the trough to a compromise of both the 12z and the 00z on speed and have that trough drop somewhat deeper and things could become very interesting. But at this point I would be happy with the solution being show which would be a big dog for March which would most likely result in snowfalls of close to a foot or more for those who fall a little north of the rain/snow line.

So right now it seems like the models are trending towards something more along the lines of a February 14 event in terms of 500 mb pattern.  SS dominated low followed by the closed upper level low, but not phased at our latitude.   Is that correct?

[PhineasC]

Kind of a weird precip hole over the region from the Euro. Dry slot at some point?

[showmethesnow]

 

So right now it seems like the models are trending towards something more along the lines of a February 14 event in terms of 500 mb pattern.  SS dominated low followed by the closed upper level low, but not phased at our latitude.   Is that correct?

Feb 2014 I assume? Don't have the great memory as others so i will have to look but your description sounds about what we see at this point.

[SomeguyfromTakomaPark]

 

Feb 2014 I assume? Don't have the great memory as others so i will have to look but your description sounds about what we see at this point.

Yeah we had a nice front-end thump in DC overnight followed by temps above freezing followed by some light snows with the ULL the next night.  Overall it was a great event I believe I measured around 10 inches and people to the NW had 10-20.

[Buddy1987]

Can someone tell me by chance what the 850s are looking like on the various models for KROA? Im worried about the upper level low to my west northwest screwing the temp profile up for me along the blue ridge here. I do like the fact the EURO deepens rapidly, so as to lock the cold air in. One would think the precip field would be more expansive with bombogenesis being induced if I did see it correctly, in which the Low deepens to 986 off VA/NC coast.

[CAPE]

From WPC-

THE SETUP IS NOT YOUR CLASSIC MILLER TYPE-A OR TYPE-B STORM BUT SEEMINGLY A COMBINATION OF THE TWO -- THERE IS FORECAST TO BE AN ALREADY-DEFINED SURFACE LOW OFF THE GA COAST LATE MONDAY (VERY MILLER TYPE-A) IN ADDITION TO AN UPSTREAM CLIPPER MOVING THROUGH THE OHIO VALLEY (LIKE A MILLER TYPE-B). HOW THE UPPER TROUGH SWINGS THROUGH THE MIDWEST WILL DETERMINE HOW THE DOMINANT LOW TRACKS -- IT COULD BE TUGGED FARTHER WEST BY A STRONGLY DIGGING TROUGH OR BE LEFT TO SWING FARTHER EAST. THIS IS ONE OF THOSE SITUATIONS WHERE THE SPREAD OF POSSIBILITIES IS NECESSARILY LARGE, ENCOMPASSING NEARLY ALL SCENARIOS FROM A LIGHT/MINOR EVENT TO AN OUTRIGHT BLIZZARD, DEPENDING ON YOUR LOCATION. 12Z ECMWF/CANADIAN LIED ON THE MORE EXTREME SIDE OF THE ENSEMBLE SPREAD (BUT WITHIN THE ENVELOPE) AS THEY MAINTAINED TWO SEPARATE UPPER LOWS DUMBBELLING THROUGH THE NORTHEAST. THE GFS RUNS WERE MORE COHERENT BUT STILL SHOWED SEPARATED VORTICITY SWINGING NORTHEASTWARD AHEAD OF THE UPPER LOW. SUFFICE IT TO SAY, THE MODELS WILL NOT GET THE DETAILS RIGHT AT THIS TIME RANGE, SO DETERMINISTIC SUCCESS IS FUTILE. RATHER, THE RANGE OF SCENARIOS SHOULD BE KEPT IN MIND.

[osfan24]

 

Yeah we had a nice front-end thump in DC overnight followed by temps above freezing followed by some light snows with the ULL the next night.  Overall it was a great event I believe I measured around 10 inches and people to the NW had 10-20.

I know people are desperate for snow, but we don't get setups where we can go kaboom very often. I'd rather go all in. Feb 2014 was an ok event, but we got thumped late overnight when few were up and then, unless you are up with PSU, you had 10-12 inches on the ground and most of it was melted by the end of the day. This being in March, I can only imagine it being worse. I'll go with the dig and phase and take my chances it's a total bust.

[SomeguyfromTakomaPark]

 

I know people are desperate for snow, but we don't get setups where we can go kaboom very often. I'd rather go all in. Feb 2014 was an ok event, but we got thumped late overnight when few were up and then, unless you are up with PSU, you had 10-12 inches on the ground and most of it was melted by the end of the day. This being in March, I can only imagine it being worse. I'll go with the dig and phase and take my chances it's a total bust.

I dunno.  I'd be very happy with 10-12 even if it melted quickly.  

[mappy]

22 minutes ago, Buddy1987 said:

Can someone tell me by chance what the 850s are looking like on the various models for KROA? Im worried about the upper level low to my west northwest screwing the temp profile up for me along the blue ridge here. I do like the fact the EURO deepens rapidly, so as to lock the cold air in. One would think the precip field would be more expansive with bombogenesis being induced if I did see it correctly, in which the Low deepens to 986 off VA/NC coast.

looking at GFS, your 850 is plenty cold when precip starts monday evening and throughout the event. 925T is touchy mid-Tuesday but I think bulk of precip is out of the area by then. 

You're fine on the Euro as well. 

[Buddy1987]

2 minutes ago, mappy said:

looking at GFS, your 850 is plenty cold when precip starts monday evening and throughout the event. 925T is touchy mid-Tuesday but I think bulk of precip is out of the area by then. 

You're fine on the Euro as well. 

Thanks a lot Mappy appreciate it. 

[gymengineer]

18 minutes ago, osfan24 said:

I know people are desperate for snow, but we don't get setups where we can go kaboom very often. I'd rather go all in. Feb 2014 was an ok event, but we got thumped late overnight when few were up and then, unless you are up with PSU, you had 10-12 inches on the ground and most of it was melted by the end of the day. This being in March, I can only imagine it being worse. I'll go with the dig and phase and take my chances it's a total bust.

I was kind of annoyed by how quickly the roads were cleared after the thump, but the bolded part just didn't happen. A lot melted the *next* day because temps spiked. But light rain with temps in the 30's during the day, before the second burst of snow, meant not much melting. 

[87storms]

Even a long duration of non sticking snow would be a coup for this Winter.  As a hobbyist, I'd be a little concerned about the progressive pattern that's existed most of the season due to a lack of blocking.  Even with an ideal track I would imagine getting a slow moving bomb would be pretty exceptional given what we've dealt with.  From the discussion above it almost sounds like this could become a NS dominant event if the lagging energy is too far East which may require more digging than what's been shown.  Might as well be in since it might be the last best chance for accumulating snow.

[mappy]

8 minutes ago, Buddy1987 said:

Thanks a lot Mappy appreciate it. 

Welcome!