February Medium/Long Range Discussion

[Bob Chill]

I'm going to start the long range winter 2020-21 disco thread. Brb

[Bob Chill]

Just now, Chris78 said:

At some point law of,averages would say something breaks our way.

Sucks seeing a string of weak runs. At least we're not inside 72 hours. That would be a dagger. Been awhile but I've seen more than a few events trend from almost nothing to a good hit in the d3-4 range on in. 2013-14 was stuffed with them but this ain't no 13-14...

[Baltimorewx]

The GFS also trended in a bad way for next weeks system Haven’t caught a break all year, hard to think it’ll happen 

[Maestrobjwa]

2 minutes ago, Baltimorewx said:

The GFS also trended in a bad way for next weeks system Haven’t caught a break all year, hard to think it’ll happen 

Dude...the Wednesday system next week is still Day 9/10...there ain't no "trending" at that range! (Just jumping, lol)

[Baltimorewx]

2 minutes ago, Maestrobjwa said:

Dude...the Wednesday system next week is still Day 9/10...there ain't no "trending" at that range! (Just jumping, lol)

Still. I’d rather at least see a better trend in cold air damming or a little bit more of a southern trajectory with the overrunning precip. We know the storm is going to cut. We need a favorable overrunning situation 

[Maestrobjwa]

1 minute ago, Baltimorewx said:

Still. I’d rather at least see a better trend in cold air damming or a little bit more of a southern trajectory with the overrunning precip. We know the storm is going to cut. We need a favorable overrunning situation 

Indeed...I still have some hope for that scenario! (it could be the only way we can score in this kind of pattern. We just need a little bit of fortune...)

[stormtracker]

Lol..European is a passing shower now.   We're going the wrong way yall

[Inverted_Trough]

Game over.  Again.

[Maestrobjwa]

1 minute ago, stormtracker said:

Lol..European is a passing shower now.   We're going the wrong way yall

Yep, basically farted out the shortwave instead of blowing it out...ack. Man we can't even get a little shortwave to work right now! Man I hope we can get a V-Day or PD weekend miracle this year...would love to be looking at a Day 7 or less threat by Friday or Saturday!

[Ji]

Lol..European is a passing shower now.   We're going the wrong way yall

It's actually sad. We cant get anything to work out. Even our bread and butter stuff

[Weather Will]

WB 0z EURO says what snow through Day 10...if it makes anyone feel better the entire megalopolis is a disaster.  Back to chasing unicorns.

[Weather Will]

WB 0z EPS for weekend.  Dream about 38. Our 2 percent chance....

[Weather Will]

Not a flake on 6Z ICON or GFS for weekend.  It's over, Grover.

[BristowWx]

3 minutes ago, Weather Will said:

Not a flake on 6Z ICON or GFS for weekend.  It's over, Grover.

That was fun for a couple of days anyway. Tough winter.  I know we have had worse winters but this one seems particularly painful. 

[LeesburgWx]

We get it within 5 days and still lose. Lol

[showmethesnow]

Haven't looked at the Euro/Eps as of yet so I won't speak for that but the 00Z GFS/GEFS and now the 06Z are running rough the last couple of runs for our chances for Sat night/Sun. And it is a pretty straight forward problem.

First pic below is from yesterday's 06Z run which was one of the better solutions throw out there on the GFS. The important players here are the SW moving east and the NS shortwave moving through NE. Now compare that to their location on the second second pic which is this mornings run. Notice that the distance between both has dramatically decreased as both the NS is lagging behind and the SW moving east has speeded up. What is happening here is that the NS is pressing down on the flow in the east not allowing the heights in front of the incoming SW to recover. So basically the SW is getting washed out as well as is it's associated surface low pressure. Not a winning look for anything more then a stray flake or two if the temps even cooperate.

We really need more separation between these two features to allow for some height builds. But it isn't even quite as simple as that. Too much separation could pooch us over as well. The flow that the eastward moving SW is embedded in is farther to the north then we would like it (thus the SW's track as well). So if we see too much separation between these two features we probably see greater height builds, thus a more supportive 500s for a stronger low. A stronger low will tend to pull farther north drawing the warm air in front of it potentially wrecking the temp profile through the region. 

 

 

 

 

[showmethesnow]

Quick glance on the Euro/Eps shows the same problem that we are seeing on the GFS. The separation between the NS and the SW moving eastward has decreased as well. This look is pretty much becoming one of the SW and the low washing out before it can even impact our region. 

[MD Snow]

CMC sniffed out that Saturday was pretty much a non event a couple days ago. Was a big red flag for me, especially considering how good it's been of late. Feb 13-14 are the dates I have in my mind at a possible flip to a more favorable pattern. There are some signs that we may be on the right side of the boundary. If we see this trend badly over the next week or so, then bring on spring! 

[showmethesnow]

5 minutes ago, MD Snow said:

CMC sniffed out that Saturday was pretty much a non event a couple days ago. Was a big red flag for me, especially considering how good it's been of late. Feb 13-14 are the dates I have in my mind at a possible flip to a more favorable pattern. There are some signs that we may be on the right side of the boundary. If we see this trend badly over the next week or so, then bring on spring! 

You better hope the EPS is more right then the GEFS. GEFS was ugly. EPS doesn't look so great either as of right now it probably argues for the boundary to mostly be north of us.

[MD Snow]

17 minutes ago, showmethesnow said:

You better hope the EPS is more right then the GEFS. GEFS was ugly. EPS doesn't look so great either as of right now it probably argues for the boundary to mostly be north of us.

Yup. Given this winter, it's a real long shot. But it's our only shot at this point. Much is stacked against us. There's still a chance and as long as there's a chance, i'll stay interested.  6z GEFS (sucks) seems to be getting us on the right side toward the end of it's run. GEPS seems to get the boundary south of us for a period between Feb 14-18. 

[osfan24]

Teleconnections people! The AO is raging positive. It's not snowing here. Ignore the models. Either the PNA needs to go positive or we need to see some serious movement in the AO to have a chance. Blinds are closed until that happens despite what these fake snow maps might tell you.

[Ralph Wiggum]

31 minutes ago, MD Snow said:

CMC sniffed out that Saturday was pretty much a non event a couple days ago. Was a big red flag for me, especially considering how good it's been of late. Feb 13-14 are the dates I have in my mind at a possible flip to a more favorable pattern. There are some signs that we may be on the right side of the boundary. If we see this trend badly over the next week or so, then bring on spring! 

Historically once we get past VD getting the boundary to stay south of us becomes a tall order, especially with little to no HL blocking and given the background  state of this winter. 

[Weather Will]

6Z GEFS is abysmal for the entire run..  No pictures for awhile.   Some would go apoplectic.

[CAPE]

15 minutes ago, osfan24 said:

Teleconnections people! The AO is raging positive. It's not snowing here. Ignore the models. Either the PNA needs to go positive or we need to see some serious movement in the AO to have a chance. Blinds are closed until that happens despite what these fake snow maps might tell you.

The advertised LR pattern on all guidance really isn't budging. It is the antithesis of what we want for cold and snow here. As for sensible weather, there is no reason to expect anything different than more of the same. Even lucking into a fluke event seems remote.

[Weather Will]

3 minutes ago, C.A.P.E. said:

The advertised LR pattern on all guidance really isn't budging. It is the antithesis of what we want for cold and snow here. As for sensible weather, there is no reason to expect anything different than more of the same. Even lucking into a fluke event seems remote.

Agreed....EURO teleconnection ensembles thru 2/20 stink (with the exception of a weak dip in EPO, but that is not enough.)  We wait to see If there is a change in the last week of February into March. 

[osfan24]

6 minutes ago, Weather Will said:

6Z GEFS is abysmal for the entire run..  No pictures for awhile.   Some would go apoplectic.

But I thought last night it said 80-90 percent for more than 3 inches of snow? Oh, so those snow maps ARE worthless?

[anotherman]

This is like a treadmill.  Things look better for a few days and then everything is crushed by reality.

[frd]

17 minutes ago, osfan24 said:

Teleconnections people! The AO is raging positive. It's not snowing here. Ignore the models. Either the PNA needs to go positive or we need to see some serious movement in the AO to have a chance. Blinds are closed until that happens despite what these fake snow maps might tell you.

Very true. You could simply forecast the winter here based on the AO and the PNA. and the NAO as well. The AO being the most important in the middle of the winter, the +PNA in the beginning and the - NAO late in the winter in terms of snowfalls. .Although the AO is king on a broad brush view among the 3 I mentioned. . 

None of these indices have been or look to go into a favorable phase for us here in the Northern Mid Atlantic any time soon.    

If you look at the indices they can tell you in a simple manner whether other players and drivers are lining up for us to get snowfall opportunities and the cold to go with it.   They even have a hand in storm tracks and if you notice we have been getting unfavorable tracks, to a degree similar to last winter, and when a track is a little better cold air is lacking .   

I also believe the poor indices lend support for not believing what the models show in the long range when it comes to snowfall potential. Don't believe long range threats will materialize in  a backdrop of poor support from the various mentioned indices above. And so far this is true, all threats have fizzled.  

This follows along as well with the importance of a AO from Don Sutherland below. Very eye opening. But, I am sure we here all recognize the importance of the AO.  

From Don S. 

<

The latest ensemble guidance continues to suggest that the Arctic Oscillation (AO) will reach extreme positive values (probably +5.000 or above for the first time since March 8, 2015):

 

Extreme AO+ situations typically lead to much above normal temperatures on the U.S. East Coast and in Europe. In large part, the consistent guidance suggesting the potential for an extreme AO+ event allowed for a high degree of confidence that the Middle Atlantic and southern New England regions would likely see a warmer to perhaps much warmer than normal February and that Europe would see a much warmer than normal February (with the warmest anomalies occurring in eastern Europe and western Russia). The cooler air that moves into Europe later this week will again yield to much warmer than normal conditions early next week.

The GEFS Day 8-12 average 500 mb height anomalies forecast shows ridging on the East Coast and over much of Europe. The 8-12 day temperature average is warmer than normal in both areas.

Finally, should the AO remain strongly positive through mid-month, the probability of significant snowfall in the Middle Atlantic region will be low during that period. Not surprisingly, the ECMWF, which had been showing a potentially major snowstorm during the second week of February has now backed off from that idea.

>>>

[mappy]

10 minutes ago, osfan24 said:

But I thought last night it said 80-90 percent for more than 3 inches of snow? Oh, so those snow maps ARE worthless?

to be fair, they do give a good picture of how awful things are. and technically on topic. so.... 

[psuhoffman]

8 minutes ago, osfan24 said:

But I thought last night it said 80-90 percent for more than 3 inches of snow? Oh, so those snow maps ARE worthless?

The tools show exactly what they say. What that run thinks is the probability of 3”.  If most of that probability it based on one event and it busts...it changes. Because the run was wrong. 

One run looking really good is not that strong a signal. When we start seeing multiple runs over days AND it’s supported by an actual good pattern then we have a strong signal. That hadn’t happened this year because the pattern has sucked. But in the past we have seen ensembles indicate snow at long range and be right.  And frozen does look to be “closer” at times the next 2 weeks so that’s why guidance has looked better at times. Still not good enough.