February Medium/Long Range Discussion

[LeesburgWx]

DT just said 90% if Mid Atlantic will see snow this weekend 

[IronTy]

1 minute ago, LeesburgWx said:

DT just said 90% if Mid Atlantic will see snow this weekend 

Ok about my earlier post...I need to rephrase.  I wish one of the mets other than DT or JB would lock in a storm 5 days out.

[CAPE]

Mount Holly AFD.. we just cant know yet.

For Saturday and Sunday...Low pressure tracks well to our north, however a strong cold front is forecast to cross our area by late in the day Saturday. Southerly flow ahead of the front will maximize the low-level warm air advection and despite cloud cover, afternoon temperatures are anticipated to get well into the 50s across the coastal plain where even some low 60s will be possible. To the north and west of here, temperatures may be held down some due to more cloud cover and a possible earlier arrival of the cold front. There may not be much in the way of precipitation with the frontal passage as the main initial forcing for ascent lifts well to our north and the upper-level trough axis is still well to our west. Shortwave energy along with a favorable mid to upper level jet though may produce a ribbon of better lift late Saturday night especially across the coastal plain. It will turn much colder and drier Saturday night in the wake of the cold front along with a northwesterly breeze.

As we go through Sunday, our sensible weather will be determined from what develops offshore of the Carolinas. Temperature-wise it will be cold. Much of the guidance is in agreement that low pressure develops along Saturday`s frontal zone that is located offshore. This occurs as the large scale upper-level trough shifts closer to the East Coast. However the low pressure placement, track and intensity will depend on how far south and east the colder air presses and also if any interaction (phasing) starts to occur between the northern and southern stream energy. Some guidance now showing a sharper upper-level trough which results in a bit more phasing and therefore a closer to the coast placement of the surface low. The ensemble guidance offers variability and as a result there remains considerable uncertainty with the details. Despite the surface low tracking offshore, the positioning of an upper-level jet looks favorable resulting in a zone of enhanced forcing for ascent for a time Sunday, especially across our coastal plain, which could result in a period of snow. Given the uncertainty and accounting for some guidance shifting closer to the coast (the National Blend of Models, NBM, responding to this), increased the PoPs a little however we are still no higher than the chance range.

[BristowWx]

2 minutes ago, LeesburgWx said:

DT just said 90% if Mid Atlantic will see snow this weekend 

It’s over

[psuhoffman]

14 minutes ago, WinterWxLuvr said:

@psuhoffman we were discussing whether the possibility exists for big model changes once we get within about 4 days. Was thinking about that and was thinking that if you’re talking temps I agree. It not gonna suddenly go from 40 and rain to 30 and snow. But when it’s delicate pieces that determine whether it’s dry or there’s 0.25-0.5 precip, then I think big changes can easily show up as you get close.

Depends what you call big changes. The fringe of a storm moving 50 miles isn’t big Imo. We know the edges and banding don’t get pinned until the very end. But we haven’t seen huge synoptic changes once inside about 100 hours.  We’re right at that now. And maybe we’re seeing convergence. Ukmet lost it’s crazy amped up solution from 0z. Gfs also trended a little south. Icon and Euro trended towards the Gfs. Toss the ggem as the outlier.  Maybe there is another curve in the next 24 hours but if not the consensus of all that guidance is likely close to the final outcome. 

[Ralph Wiggum]

4 minutes ago, Weather Will said:

WB 18Z NAM at 84, I know…

Without the DGEX, we just can't know.

[nj2va]

I thought the NAM looked pretty good at 84.

[psuhoffman]

Just now, nj2va said:

I thought the NAM looked pretty good at 84.

I thought the NAM at 84 looked like the NAM at 84 

[Herb@MAWS]

LWX afternoon disco not bullish but also not discounting snow possibilities. 

[WinterWxLuvr]

3 minutes ago, psuhoffman said:

Depends what you call big changes. The fringe of a storm moving 50 miles isn’t big Imo. We know the edges and banding don’t get pinned until the very end. But we haven’t seen huge synoptic changes once inside about 100 hours.  We’re right at that now. And maybe we’re seeing convergence. Ukmet lost it’s crazy amped up solution from 0z. Gfs also trended a little south. Icon and Euro trended towards the Gfs. Toss the ggem as the outlier.  Maybe there is another curve in the next 24 hours but if not the consensus of all that guidance is likely close to the final outcome. 

I’ll say this. I honestly think at this point I’m looking at a range of 0 snow to up to 6” of snow. I think that’s very much within the realm of possibilities. I think that leaves a lot of room for big changes. Now if you paint a swath 200 miles wide and say snow is possible here on Sunday, and call that locked in, then yeah we’re locked in.

Youre never gonna see models go from a trace to 20”. That’s not what I’m talking about.

[WxUSAF]

1 minute ago, nj2va said:

I thought the NAM looked pretty good at 84.

I hate saying this but it did. Enough spacing at first to get the frontal snow going, but the northern stream diving in fast to probably help juice up the coastal. And the northern stream diving in farther west.

[ryanconway63]

7 minutes ago, BristowWx said:

It’s over

DT kiss of death....forget about this one

[LeesburgWx]

I fully expect the GFS to hold here at 18z. It’s been pretty locked in now for 3-4 consecutive runs. It is in it’s King wheelhouse. Just need that bullseye stripe to come north 30-40 miles.

[Ralph Wiggum]

Someone refresh my memory....what is the order of forecasts upcoming? Is it first thoughts, first draft, preliminary first final guess, first guess, second  thoughts, first revision and guess, second draft, second guess, final thoughts, final draft, final wheel spin, final guess, first forecast still?

[psuhoffman]

12 minutes ago, WinterWxLuvr said:

I’ll say this. I honestly think at this point I’m looking at a range of 0 snow to up to 6” of snow. I think that’s very much within the realm of possibilities. I think that leaves a lot of room for big changes. Now if you paint a swath 200 miles wide and say snow is possible here on Sunday, and call that locked in, then yeah we’re locked in.

Youre never gonna see models go from a trace to 20”. That’s not what I’m talking about.

Right now we haven’t seen stability or consensus reached. We’re right at 100 though so that suggests we’re about to see guidance converge.  Once that happens…recent history suggests there will be noise and outlier runs each cycle but whatever the preponderance consensus is will be close to the final result. 
 

If in the next 24 hours we see the Gfs and euro converge on a snowfall targeting southeast of DC again…then that’s probably going to be the end result. Maybe we sneak in a couple inches. Maybe we get nothing. I’m not even that worried about it. I’m in this game hunting the flush hits so frankly if we fringe or get skunked isn’t much difference to me. Both leave me equally unsatisfied. I don’t complain. Storms miss. Oh well. Just saying I’m in this for the big storms. And if guidance says it’s a miss once inside 100 hours it’s very rarely going to become anything significant and I’m not really interested in praying for some miracle trend just to eek out another 2” 

[SnowGolfBro]

Just now, LeesburgWx said:

I fully expect the GFS to hold here at 18z. It’s been pretty locked in now for 3-4 consecutive runs. It is in it’s King wheelhouse. Just need that bullseye stripe to come north 30-40 miles.

Or juice up the current stripe so as to include Leesburg in the 6-10 range.  of course these are the type of comments that precede the following comments:

next

wide right

wheres the storm

might need a human sacrifice

[Scarlet Pimpernel]

1 minute ago, Ralph Wiggum said:

Someone refresh my memory....what is the order of forecasts upcoming? Is it first thoughts, first draft, preliminary first final guess, first guess, second  thoughts, first revision and guess, second draft, second guess, final thoughts, final draft, final wheel spin, final guess, first forecast still?

You forgot the "phone a friend" forecast!   But not sure where that fits in to the overall order!

[LeesburgWx]

3 minutes ago, SnowGolfBro said:

Or juice up the current stripe so as to include Leesburg in the 6-10 range.  of course these are the type of comments that precede the following comments:

next

wide right

wheres the storm

might need a human sacrifice

Lol, I haven’t dropped the ‘We suck’ comment yet this year…

[CAPE]

Latest NBM snow map for the hell of it. Waiting for HH GFS to get rolling while enjoying a HH Coffee Stout.

 

 

[weathercoins]

23 minutes ago, LeesburgWx said:

DT just said 90% if Mid Atlantic will see snow this weekend 

It’s ALEET time, baby 

[RevWarReenactor]

Psu is already in his “big storm only” mode. Which doesn’t usually happen till late Feb or early March? Now I know things are perhaps winding down early this year…;-)

[psuhoffman]

@WinterWxLuvr if you want a  snow of significance all im saying is hope in the next couple cycles we see  guidance converge on a 6z Gfs type solution. Even the 12z is close enough that’s the kind of look 72-100 hours we can work with and get some minor adjustments to make it an event worth the time. But if the Gfs moves towards the euro and come tomorrow the majority of guidance  had the snowfall southeast of 95…were pretty much cooked. People will say things like “it’s still 72 hours out plenty of time” to make themselves feel better but how often has that worked out? 

[CAPE]

4 minutes ago, RevWarReenactor said:

Psu is already in his “big storm only” mode. Which doesn’t usually happen till late Feb or early March? Now I know things are perhaps winding down early this year…;-)

I think he is always in that mode lol. I lived up that way for 12 years (at 900 ft) and never felt like I was in some sort of magical place for snow. I never kicked a 1-3 incher out of bed.

[SnowGolfBro]

7 minutes ago, LeesburgWx said:

Lol, I haven’t dropped the ‘We suck’ comment yet this year…

Lol, yes my list was the family friendly version lol. As time for snow runs shorter the reactions get slightly more violent when we get the rug pulled. Hoping this time we trend into a solid storm!

[Maestrobjwa]

The model that sucks has an 18z run that doesn't (if you discount the sloppy precip depiction, lol)

[Baltimorewx]

8 minutes ago, Maestrobjwa said:

The model that sucks has an 18z run that doesn't (if you discount the sloppy precip depiction, lol)

Yeah its .5-.6 Precip for a good chunk of us. Just running a bit warm

[psuhoffman]

8 minutes ago, RevWarReenactor said:

Psu is already in his “big storm only” mode. Which doesn’t usually happen till late Feb or early March? Now I know things are perhaps winding down early this year…;-)

What are you talking about. I’m always in that mode. Only exception is around Xmas or if it’s a crazy cold pattern and I can build snowpack and keep it. Otherwise it’s go big or go home.  
 

I’m not really a big “snow” fan I’m a big snowstorm fan. Huge flakes and 3”/hour rates or bust.  It doesn’t have to be huge totals. The squall where I got 3” in like 45 mins 2 years ago was awesome.  But there has to be something dynamic about it.  3” of light snow that’s going to melt within a couple days does nothing for me.  Back in 2015 I was annoying people because there was a 3-5” WAA wave storm 2 days out and I was rooting against it because there was a better setup to get a big amplified bomb right behind it but only if that WAA wave got squashed. I was 100% willing to kill a guaranteed 4” for like a 20% chance at a big storm.   
 

But I know those big storms are rare and unlikely any given threat and I’m not going to clog up the threads crying and complaining when they don’t happen.  But it’s probably a good idea for people to know where my analysis is coming from. If someone else is just looking for 1-2” of snow they might get a more negative perception then is reality from my analysts since I’m only analyzing our chances of a flush hit. 

[WinterWxLuvr]

16 minutes ago, psuhoffman said:

@WinterWxLuvr if you want a  snow of significance all im saying is hope in the next couple cycles we see  guidance converge on a 6z Gfs type solution. Even the 12z is close enough that’s the kind of look 72-100 hours we can work with and get some minor adjustments to make it an event worth the time. But if the Gfs moves towards the euro and come tomorrow the majority of guidance  had the snowfall southeast of 95…were pretty much cooked. People will say things like “it’s still 72 hours out plenty of time” to make themselves feel better but how often has that worked out? 

We are agreeing while seeming to disagree. I consider a 3-4” snow to be a big deal. If the euro, for instance, moves from 0” to 3” for my yard, I consider that a big move.

Its all about perspective.

[clskinsfan]

18Z RGEM is a pretty big improvement over its 12Z run. Leads me to believe it would be a decent event. 

[psuhoffman]

14 minutes ago, CAPE said:

I think he is always in that mode lol. I lived up that way for 12 years (at 900 ft) and never felt like I was in some sort of magical place for snow. I never kicked a 1-3 incher out of bed.

I don’t feel I have some right to said storms. I don’t feel slighted and go off when they don’t happen. And I won’t kick a 1-3” snow out of bed. But I’m not wasting time tracking that either. If it happens fine. But the target is higher to me lol.