Mid January/Mid February Medium/Long Range Discussion

[Ralph Wiggum]

So I guess I have more learning irt thermals and precip type. How is it that 850s are below freezing, 700s are very well below freezing as expected, surface temps mid 30s, 540 line is south and east, but raining in many areas? I thought especially during prime climo outside of surface temps those others indicators were a shoo-in for frozen? 2m temps arent exactly scorching until you get east of the fall line if you consider 40 a torch. 

[Ralph Wiggum]

1 hour ago, showmethesnow said:

The morning GFS spit out a solution that was oh so close to potentially a very good outcome for our region. Typically don't give much weight to op runs vs. ensembles outside of 5 days but in this case with the key players on the field just outside of 5 days and the op runs finer details with smaller scale features vs the smoothing of the ensembles i might make an exception.

Below we have the vort map leading into our east coast storm. We have 3 pieces of energy to take note of (North stream, Mid-stream and a Southern stream). What we see here just misses from being a triple phaser in a very favorable location for our region. What we have is the MS dropping down the backside of the SS with the NS waiting in the wings in a favorable locale to drop down the backside of any potentially phasing of the MS and SS. Unfortunately what we see on this run is that the SS escapes too quickly to the east and the MS misses it. This leaves the NS dropping down with a shallower drop and we see no phasing between any of them. You can see the result on the second map below.

But as I said, this was oh so close. Slow that SS energy down by 6 hours or speed up the MS by 6 and we do see a phase between the MS and the SS. We see that initial phase and then then chances are good we would see a deeper drop from the NS as it gets drawn into the initial phase giving us a triple phaser in a favorable locale for our region. Now I know the issue is/has been the temps leading into the system. But if we were in fact to see a triple phase with the general overall trough setup displayed below I don't think temps would be an issue besides the initial onset of any precip. Would probably be a case of rain to wet snow to dry powder. And this is due to the fact we would see the NS bring with it the colder air needed in the upper levels. Biggest initial handicap would be the lower and surface level temps but more then likely they would be quickly overcome. Now you may look at the surface compared to the upper levels and say, 'but the surface low pressure is already exiting the scene before the cold air can arrive. But if you look at the second map below what we are seeing is that the low pressure is forming on the lead SS energy that is running ahead of everything else. BUT... if we had seen that SS 6 hours slower with a phase. We would see that surface low delayed as well giving time for the cold to catch up to it. Conversely, if we had seen a 6 hour quicker MS energy and phase with the SS chances are good we would see a quicker response eastward from the NS and bringing the cold with it. Pure conjecture on my part, but if we would have seen slower SS energy (quicker MS) I could very well have seen this end up being a bombing low somewhere between OBX and OC as the 500's catch up and start stacking to the surface with a track leading up to the bench mark.

 

 

 

 

 

What do the Euro and CMC do that there really isnt even a storm? I would look but cant atm. Ty.

[psuhoffman]

6 minutes ago, Ralph Wiggum said:

So I guess I have more learning irt thermals and precip type. How is it that 850s are below freezing, 700s are very well below freezing as expected, surface temps mid 30s, 540 line is south and east, but raining in many areas? I thought especially during prime climo outside of surface temps those others indicators were a shoo-in for frozen? 2m temps arent exactly scorching until you get east of the fall line if you consider 40 a torch. 

It’s the surface temps.  38-40 might not be a torch but it’s not gonna work for snow. Verbatim that’s the look of rain mixing with slush bombs during heavy precip.  Not saying it’s correct but those surface temps don’t support snow. 

[psuhoffman]

8 minutes ago, Ralph Wiggum said:

What do the Euro and CMC do that there really isnt even a storm? I would look but cant atm. Ty.

They wash out the MS and SS vorts there and so it’s all northern stream. The gem tries to kick up a NS dominant system the euro simply suppressed the SS wave. 

[WinterWxLuvr]

I at least expected a comment or two on how the euro, the model that makes only graceful and small changes, went from this 

to this 

in 12 hours.

I found that to be more than a little humorous.

[psuhoffman]

5 minutes ago, WinterWxLuvr said:

I at least expected a comment or two on how the euro, the model that makes only graceful and small changes, went from this 

to this 

in 12 hours.

I found that to be more than a little humorous.

Ignore the low off Norfolk and look at the whole picture. Everything else is pretty much the same. That low is tenuous based on exactly how the stj wave ejects. If it leaves too much behind and doesn’t phase it ends up suppressed. If the wave ejects healthy enough it phases and we end to with stronger storm. It’s a minor detail that leads to one major difference but on a pattern level the euro isn’t flopping around in the larger sense. 

[Scraff]

4 minutes ago, WinterWxLuvr said:

I at least expected a comment or two on how the euro, the model that makes only graceful and small changes, went from this 

to this 

in 12 hours.

I found that to be more than a little humorous.

We toss! Lol, but how is this not a good look? Am I missing something? Of course I am. 

[psuhoffman]

9 minutes ago, WinterWxLuvr said:

I at least expected a comment or two on how the euro, the model that makes only graceful and small changes, went from this 

to this 

in 12 hours.

I found that to be more than a little humorous.

Furthermore “the euro is rock steady” isn’t a thing anymore.  I don’t know if it’s because it runs 4 times a day now vs once back in the day. Or if it’s higher resolution made it more accurate but also more prone to tangents. But it definitely jumps around with specifics run to run the last several years. But usually it’s goalposts are closer to the reality and it tends to catch on first. But it’s not 100% and you can’t just rip and read it’s long range output as a gospel forecast. 

[PhineasC]

The Cosgrove references are taking me back to 2004. 

[tombo82685]

1 hour ago, Ralph Wiggum said:

So I guess I have more learning irt thermals and precip type. How is it that 850s are below freezing, 700s are very well below freezing as expected, surface temps mid 30s, 540 line is south and east, but raining in many areas? I thought especially during prime climo outside of surface temps those others indicators were a shoo-in for frozen? 2m temps arent exactly scorching until you get east of the fall line if you consider 40 a torch. 

 

 

 

 

prior to the low coming up, the HP that is over the area slides to the east/southeast. With that positioning you get southerly flow at the surface which warms the BL temps and thus a rainy outcome despite an overall good track

 

[Ralph Wiggum]

1 hour ago, psuhoffman said:

It’s the surface temps.  38-40 might not be a torch but it’s not gonna work for snow. Verbatim that’s the look of rain mixing with slush bombs during heavy precip.  Not saying it’s correct but those surface temps don’t support snow. 

I know it's not this sub but look up into PA....2m temps are 33-35. Is that the mythical "33 and rain" scenario?

[psuhoffman]

35 minutes ago, losetoa6 said:

I thought the 18z Eps last night looked pretty darn good at 144. Now the 6z looks pretty strungout and sheared in the stj.  Looks to leave a good bit more energy behind or  gets crushed .

 

 

That’s a definite degradation 

[psuhoffman]

The eps and geps both have a very workable pattern at the end.  Neutral AO. EPO ridge. Gefs is a train wreck. Reloads the same +AO. Pac ridge north of Hawaii pattern. Normally I would say with the CFS, EPS, GEPS all showing a similar progression toss the GEFS. And science would say that’s the way to go. But would anyone be surprised if in this one case the gefs schools all the other guidance? 

[showmethesnow]

1 hour ago, Ralph Wiggum said:

So I guess I have more learning irt thermals and precip type. How is it that 850s are below freezing, 700s are very well below freezing as expected, surface temps mid 30s, 540 line is south and east, but raining in many areas? I thought especially during prime climo outside of surface temps those others indicators were a shoo-in for frozen? 2m temps arent exactly scorching until you get east of the fall line if you consider 40 a torch. 

 

The sounding is crap though. This is for up around Hanover and temps are above freezing from just under the 850's all the way down to the surface. Awful deep warm layer to try to overcome even with very good rates. And the soundings get even worse as you move down towards DC. Only finally see improvement as the surface and lower level winds shift from the north as the low is pulling away. 

 

[psuhoffman]

Gefs makes no sense with its mjo forecast. The geps goes crazy into phase 5/6. Cfs and eps are meaderong in the COD. The gefs goes strong into phase 2/3 which are cold phases in the east February.  So the guidance with the worst mjo looks best. The one with a good mjo looks like dog crap. Go figure. 

[dallen7908]

1 hour ago, psuhoffman said:

Furthermore “the euro is rock steady” isn’t a thing anymore.  I don’t know if it’s because it runs 4 times a day now vs once back in the day. Or if it’s higher resolution made it more accurate but also more prone to tangents. But it definitely jumps around with specifics run to run the last several years. But usually it’s goalposts are closer to the reality and it tends to catch on first. But it’s not 100% and you can’t just rip and read it’s long range output as a gospel forecast. 

Yes I suspect the surface reflection of the 500 hPa pattern is more sensitive to small changes in the overall pattern at higher resolution; however, perception also plays a role.  I'm not sure the Euro has ever been rock steady over the 6-10 day period we (are forced to ) focus on during periods non-conducive to snow

[Ji]

Ugh icon sheared and weak

[Bob Chill]

Medium range upper level madness this week. What seemed a little simple is now very complicated. I'll wave the white flag and save myself the stress

[psuhoffman]

3 minutes ago, dallen7908 said:

Yes I suspect the surface reflection of the 500 hPa pattern is more sensitive to small changes in the overall pattern at higher resolution; however, perception also plays a role.  I'm not sure the Euro has ever been rock steady over the 6-10 day period we (are forced to ) focus on during periods non-conducive to snow

Excellent point. In a better year when we aren’t always looking at day 10 ghosts by the time one threat either fizzles or is over the next one we turn our attention too is only 5 days out.  We don’t even notice the day 7+ shenanigans. Plus 10-20 years ago we didn’t tend to look that far out. 20 years ago nothing even went that far. When I started analyzing guidance in the late 90s at PSU the MRF/AVN (what became the GFS) ran to 10 days at 0z and 5 at 12z. The euro was only once a day to 7 days. The eta and ngm ran to 48. Nogaps to 6. And that was it. And when we would have our daily model analysis meetings at the weather station day 5 stuff was considered the same way most think of day 15 now.  We barely paid it any attention beyond general pattern trends.  So the euro probably seemed less jumpy when it ran once a day and only to 7 but most didn’t even pay attention past 4/5 days. 

[Ji]

Medium range upper level madness this week. What seemed a little simple is now very complicated. I'll wave the white flag and save myself the stress

Yea..thought the bob chill storm would be easy snow and it sheared so I figured that would leave room for a big storm to follow and that is now looking sheared. It doesn't want to snow this year

[Bob Chill]

1 minute ago, Ji said:

6 minutes ago, Bob Chill said:

Medium range upper level madness this week. What seemed a little simple is now very complicated. I'll wave the white flag and save myself the stress

Yea..thought the bob chill storm would be easy snow and it sheared so I figured that would leave room for a big storm to follow and that is now looking sheared. It doesn't want to snow this year

I'm guilty of this too so not throwing rocks at glass houses but we all tried to force fit the upcoming setup into a good chance at snowfall when in reality the chances were as slim as any other time this year. The predominant theme of low chances for snow and high chances of disappointment are still firmly in control

[psuhoffman]

5 minutes ago, Bob Chill said:

Medium range upper level madness this week. What seemed a little simple is now very complicated. I'll wave the white flag and save myself the stress

The simple idea might be a lost cause now. You only have to go out 72 hours to see all the various shortwaves clearly. They are real. And all over the place. And that probably means without a phase nothing can amplify enough.  Too much splitting and competition of the energy.  Even if it made it here a weak strung out wave won’t work. So were left rooting for a phased bomb now as the only option. Good luck with that both getting it and figuring out all those shortwaves at range. 

[WeatherPSU]

The trend is not our friend in 2020. Enough said. 

[psuhoffman]

1 minute ago, WeatherPSU said:

The trend is not our friend in 2020. Enough said. 

Fog fail 

[Solution Man]

New Low Point NLP

[clskinsfan]

I still see tons of upcoming chances for flakes on the Icon. 

[frd]

2 minutes ago, clskinsfan said:

I still see tons of upcoming chances for flakes on the Icon. 

The accuracy and verification of the icon is .......  seriously I think it is not terrible but not in the same league as the better models.  

When was the last time is had a win over over models? 

[frd]

 

Nothing like consensus, and shame on me for even looking at a product such at this, but still it is amusing. 

 

[psuhoffman]

Gfs seems more amplified than the icon early on. Slower too. Of course we might need slower now. Without the NS phase it’s likely to be too weak to work with all the shortwaves knocking down heights on top of it. A fast moving weak stj wave ends up like the icon.  Of course the slow phase bring temp issues. So would you prefer the rock or the hard place?

[clskinsfan]

Just now, frd said:

The accuracy and verification of the icon is .......  seriously I think it is not terrible but not in the same league as the better models.  

When was the last time is had a win over over models? 

I dont look at the models for accuracy outside of 4 days. I look for chances to score. And all of the models are showing chances for snow. Maybe not big storms. But chances.