December/January Medium/Long Range Discussion

[psuhoffman]

I hope everyone enjoyed our dead period because I have a feeling that things are going to be busy in here starting soon and for an extended period.  We are starting to see the first signs of the pattern flip towards New Years.  Once the lower heights near AK retrograde west watch out.  The rest of the pattern progression is just the snowball rolling down the mountain.  Even during this crap pattern troughs have generally tried to dig into the east, and we have had storms, but there just wasn't any cold air thanks to the trough over Alaska blasting maritime air across the CONUS.  But as soon as that shuts off things should get exciting.  

There can be a threat as the pattern flip happens, but don't be surprised if we have to let this ferment a while before we score.  But every year is different and just because most of the analogs suggest January 15 on is when to look for big snow doesn't mean we can't get lucky before that, but don't be discouraged if the interior and New England cash in before us.  In many of the analogs there were some storms that missed us just to the NW during the transition period in early January before we got hit later in the month.  As the pattern matures and blocking develops our chances will increase.  All in all we are starting to see the changes in the long range guidance...the ensembles are now beginning to pick up on the first steps towards what the seasonal guidance has been saying is coming, and right on time.  

[BristowWx]

3 minutes ago, frd said:

Hmm, to be honest if this is all we get I am very dissapointed :-)   but I take ! 

And, OMG to the NE of off.   

As for NH snow cover decline posted yesterday by late Jan might be near the top again. 

Also, listened to DT this AM on new post , very gung ho for a good Jan. No surprise, right,  but nice to have concensus.   

 

 

 

 

 

that doesn't surprise me at all.  My thought is that El Nino, while known for being wet, doesn't mean cold but more likely marginal temps south of PHL.  We need BN temps to get snow...most of us anyway.  Further north less of a factor.  So I do think we see our fair share of precip events not sure if all but a few will be white.  Just my two cents. 

[psuhoffman]

6 minutes ago, frd said:

Hmm, to be honest if this is all we get I am very dissapointed :-)   but I take ! 

And, OMG to the NE of us.   

As for NH snow cover decline posted yesterday by late Jan might be near the top again. 

Also, listened to DT this AM on new post , very gung ho for a good Jan. No surprise, right,  but nice to have concensus.   

 

 

 

 

 

DT did call for this warm up and then a flip to cold after the holidays a long time ago...he was very bullish on this winter and so far has been pretty good with timing the pattern progressions... we will see.  

[frd]

4 minutes ago, BristowWx said:

that doesn't surprise me at all.  My thought is that El Nino, while known for being wet, doesn't mean cold but more likely marginal temps south of PHL.  We need BN temps to get snow...most of us anyway.  Further north less of a factor.  So I do think we see our fair share of precip events not sure if all but a few will be white.  Just my two cents. 

You might be correct but I have a feeling , nothing super scientific to attach to it. but I think real cold risk are elevated, meaning I think based on the outcomes of the strat event, whatever form it takes and the outcome region, we could have some very cold temps where rain is not an issue. 

I know some mets mention Miler Bs , other talk of storms going South of us too, depending on blocking. 

In some cases of early season strat events that impact us in a good way the potential exsists for a long duration snow cover as well. 

[SnowGolfBro]

We are not really having a big warm up. A few days above average but mostly the warm up has been transient and muted. Maybe a good sign as we get closer to a better snow pattern

[Eskimo Joe]

Just now, SnowGolfBro said:

We are not really having a big warm up. A few days above average but mostly the warm up has been transient and muted. Maybe a good sign as we get closer to a better snow pattern

We'll be close to 60 degrees on Friday & Saturday.  

[SnowGolfBro]

Just now, Eskimo Joe said:

We'll be close to 60 degrees on Saturday.  

No doubt. But it’s not like we are having 2 weeks in the 50s. An anomalous warm day or two doesn’t bother me 

[Ji]

2 hours ago, Wonderdog said:

It's ripe with possibilities!

not really. I think Dec 28 is way to early for us to get a winter storm

[Bob Chill]

Just now, Ji said:

not really. I think Dec 28 is way to early for us to get a winter storm

Agree. Front side of the transition away from Pac puke is process. Models are likely showing the chances coming too quickly. By this time next week we should be back to legit d10+ fantasy threats tho

[poolz1]

9 minutes ago, psuhoffman said:

I hope everyone enjoyed our dead period because I have a feeling that things are going to be busy in here starting soon and for an extended period.  We are starting to see the first signs of the pattern flip towards New Years.  Once the lower heights near AK retrograde west watch out.  The rest of the pattern progression is just the snowball rolling down the mountain.  Even during this crap pattern troughs have generally tried to dig into the east, and we have had storms, but there just wasn't any cold air thanks to the trough over Alaska blasting maritime air across the CONUS.  But as soon as that shuts off things should get exciting.  

There can be a threat as the pattern flip happens, but don't be surprised if we have to let this ferment a while before we score.  But every year is different and just because most of the analogs suggest January 15 on is when to look for big snow doesn't mean we can't get lucky before that, but don't be discouraged if the interior and New England cash in before us.  In many of the analogs there were some storms that missed us just to the NW during the transition period in early January before we got hit later in the month.  As the pattern matures and blocking develops our chances will increase.  All in all we are starting to see the changes in the long range guidance...the ensembles are now beginning to pick up on the first steps towards what the seasonal guidance has been saying is coming, and right on time.  

Just curious as to your thoughts on the MJO progression....I was actually thinking that we may see signs of life in the LR due to the phase 5 look but as models see the possible progression toward phase 6 we could see a slight pull back in the first week of Jan.  After that it's game on as phases 7-3 are decent/great.  Maybe the progression will look more like a step down instead of a snap to winter....Which I would prefer.... What comes in fast seems to leave fast.

 

[frd]

3 minutes ago, poolz1 said:

ust curious as to your thoughts on the MJO progression....I was actually thinking that we may see signs of life in the LR due to the phase 5 look but as models see the possible progression toward phase 6 we could see a slight pull back in the first week of Jan.  After that it's game on as phases 7-3 are decent/great.  Maybe the progression will look more like a step down instead of a snap to winter....Which I would prefer.... What comes in fast seems to leave fast.

I will let @psuhoffman answer that but I recommend DT's 6 hour old , This Week in Weather video, where he talks about that. Some stall it others move it along but the video is a good visual tool. 

Interesting side note, it has a very high amplitude right now. But, this is also part of why we are having the strat event , tropical forcing , all part of the puzzle. 

Think back too to what , Webb weather, Spillo , etc., mentioned that the current phase of the QBO tends to favor stat events at this time.   

 

 

[pasnownut]

59 minutes ago, nj2va said:

Certainly doesn’t seem a shortage of strong lows and moisture laden storms. Keep that up when the pattern flips and it’ll be busy in here. Storm mode for weeks. Ha

I'd only be cautious that while the pattern flip looks to be coming, dont assume the STJ will end up where we want/need it.  Suppression depression is something that we need to be reminded of.  Sure hope that isnt the case, but as we saw 2 weeks ago, it is a possibility.

[BristowWx]

6 minutes ago, Ji said:

not really. I think Dec 28 is way to early for us to get a winter storm

not buying NYE/NYD either.  MLK timeframe hopefully. 

[frd]

Seeing the first signs possibly of the decline in the AO. ( and staying negative maybe ) Will be interesting to see this in a week and then again two weeks 

 

[psuhoffman]

Just now, BristowWx said:

that doesn't surprise me at all.  My thought is that El Nino, while known for being wet, doesn't mean cold but more likely marginal temps south of PHL.  We need BN temps to get snow...most of us anyway.  Further north less of a factor.  So I do think we see our fair share of precip events not sure if all but a few will be white.  Just my two cents. 

From about January 1 to Feb 20th we don't need big negative departures to get snow.  Yes on a sunny day our high with "normal" temperatures will be around 40-45 in the city but with a dew point well below freezing and 850 temps plenty cold enough to support snow that is not indicative that temperatures would be a problem if we got a storm.  There are times when temperatures can ruin a good storm track...like this weekend, but often that is because the pattern is absolute crap due to something like an AK vortex or a raging positive AO/NAO.  If the pattern is at least decent, with a "normal" air mass in place, the storm track and getting a favorable SLP and H5 pass is more important to our snow chances than the surface temperatures on a sunny day before and after the storm.  Having a high of 42 at DCA the day before a storm is not in itself indicative that it is too warm to snow.   The pattern being advertised on all the long range guidance will be plenty cold enough if we get a good storm track. 

The more likely reason there are a lot of individual members that do not show much snow here are that not all of them agree on the pattern.  Out of the 50 members there are going to be a few that don't develop the same good look.  Then they, of course, would favor to our north because in a less ideal pattern for us, north of here still can get snow.  Then there is the fact that a few members probably do have a good pattern but bad luck is the problem.  A few miss us to the south with the best snow.  There are a couple that really crush our area also.  And frankly getting those to show something much above climo in the long range is difficult.  That is one of the better looking snowfall means I have ever seen on the euro weeklies when you consider that almost all of that snow comes after day 20.  

On the list of things I am worried about in this coming pattern, New England having more snow then us on the 45 day weekly mean is like on page 7 next to some cow in ohio farting in the wrong direction.  

[Yeoman]

20 minutes ago, BristowWx said:

not buying NYE/NYD either.  MLK timeframe hopefully. 

Prez day is looking good on the quarterlies

[psuhoffman]

23 minutes ago, poolz1 said:

Just curious as to your thoughts on the MJO progression....I was actually thinking that we may see signs of life in the LR due to the phase 5 look but as models see the possible progression toward phase 6 we could see a slight pull back in the first week of Jan.  After that it's game on as phases 7-3 are decent/great.  Maybe the progression will look more like a step down instead of a snap to winter....Which I would prefer.... What comes in fast seems to leave fast.

 

The long range guidance is ambiguous past day 10 with the MJO.  Most of it starts to de-amplify towards the COD.  But the long range guidance has been under doing the amplitude for a while now so it wouldn't surprise me of it does go into phase 6, and yes that could cause a temporary pull back of the cold, but probably not very long.  And I am not so sure phase 5 is even really going to help because the SOI is in nina territory so why would using a nino phase 5 correlation really work?  Perhaps other factors are about to take over.  The MJO correlation is not 1:1, it can be overcome, especially if the wave weakens some.  Lately the MJO wave has been flexing and overwhelming the pattern but that isn't always the case.  Either way, worse case scenario we get a week through phase 6 and have to wait but that would only be a temporary problem so I am not going to sweat it.  Besides I am still sticking to my original call that after January 15th is our best chance for snow so having punt the first week of January won't bother me as long as things are still on track in the overall progression and we see the look up top heading towards what we want.  That was a whole lot of ways to basically say I don't know...but I don't think its a problem in the longer term picture either way.  

[poolz1]

9 minutes ago, psuhoffman said:

The long range guidance is ambiguous past day 10 with the MJO.  Most of it starts to de-amplify towards the COD.  But the long range guidance has been under doing the amplitude for a while now so it wouldn't surprise me of it does go into phase 6, and yes that could cause a temporary pull back of the cold, but probably not very long.  And I am not so sure phase 5 is even really going to help because the SOI is in nina territory so why would using a nino phase 5 correlation really work?  Perhaps other factors are about to take over.  The MJO correlation is not 1:1, it can be overcome, especially if the wave weakens some.  Lately the MJO wave has been flexing and overwhelming the pattern but that isn't always the case.  Either way, worse case scenario we get a week through phase 6 and have to wait but that would only be a temporary problem so I am not going to sweat it.  Besides I am still sticking to my original call that after January 15th is our best chance for snow so having punt the first week of January won't bother me as long as things are still on track in the overall progression and we see the look up top heading towards what we want.  That was a whole lot of ways to basically say I don't know...but I don't think its a problem in the longer term picture either way.  

Ha!  I understand your uncertainty....Appreciate the response.  

[Fozz]

1 hour ago, frd said:

Hmm, to be honest if this is all we get I am very dissapointed :-)   but I take ! 

And, OMG to the NE of us.   

As for NH snow cover decline posted yesterday by late Jan might be near the top again. 

Also, listened to DT this AM on new post , very gung ho for a good Jan. No surprise, right,  but nice to have concensus.   

 

 

 

 

 

Honestly I think 12-16" of snow through the end of January would be pretty good. A lot of great winters had less than that. February is often our best month, so let's hope it gets even better by then.

[frd]

Remember I mentioned cold risks despite the El Nino , well check this out the link below, in addition to Todd's reply there are some very cold and harsh winters when things flip like this in the past.( week 51 minus week 50 GWHDDs )

 

Todd Crawford  @tcrawf_nh Dec 17

This is fascinating, the biggest mid-late Dec warmups (week 51 minus week 50 GWHDDs)

are associated with some absolutely epic winters, esp. 1962, 1977, 1978, 2002

 

 

https://mobile.twitter.com/N565UA/status/1074651605641900032

We're now in the midst of the largest CONUS warm up for this time of year in 56 yrs And, 2nd largest since at least 1950 GWs 51 Minus 50 CONUS TDDs MDA

 

 

 

 

[nj2va]

1 hour ago, pasnownut said:

I'd only be cautious that while the pattern flip looks to be coming, dont assume the STJ will end up where we want/need it.  Suppression depression is something that we need to be reminded of.  Sure hope that isnt the case, but as we saw 2 weeks ago, it is a possibility.

No doubt.  We need a list of things to break our way to get a snowstorm here in the Mid-Atlantic and a favorable pattern doesn't automatically equal snow here.  But with that said, the pattern advertised by the weeklies, seasonal forecasts, etc in January and February increases the chances to above average for snow.  I find it hard to believe *if* that advertised pattern happens, we'd be shut out.  

[Maestrobjwa]

1 hour ago, pasnownut said:

I'd only be cautious that while the pattern flip looks to be coming, dont assume the STJ will end up where we want/need it.  Suppression depression is something that we need to be reminded of.  Sure hope that isnt the case, but as we saw 2 weeks ago, it is a possibility.

Seems like our only weak-mod El Nino failures  have come as a result of repeated suppression...My question is if we will be able to tell a month from now if that will be a trend for the winter. Wouldn't surprise me...that's why the talk of good looks overhead and such isn't giving me much confidence.

[Chris78]

Not an awful look at the end of the Run. Not there yet but you can see it heading in the direction we want.  

[Maestrobjwa]

1 hour ago, frd said:

Remember I mentioned cold risks despite the El Nino , well check this out the link below, in addition to Todd's reply there are some very cold and harsh winters when things flip like this in the past.( week 51 minus week 50 GWHDDs )

 

Todd Crawford  @tcrawf_nh Dec 17

This is fascinating, the biggest mid-late Dec warmups (week 51 minus week 50 GWHDDs)

are associated with some absolutely epic winters, esp. 1962, 1977, 1978, 2002

 

 

https://mobile.twitter.com/N565UA/status/1074651605641900032

We're now in the midst of the largest CONUS warm up for this time of year in 56 yrs And, 2nd largest since at least 1950 GWs 51 Minus 50 CONUS TDDs MDA

 

 

 

 

Seemed to only indicate a snowy winter every other time it happened. So...in chronological order (using BWI totals as I usually do), here are the Decembers this kind of warmup happened...and what happened in the winter that followed:

Dec 1957-above average

Dec 1958--below average

Dec 1962-average winter

Dec 1972-below average (strong nino)

Dec 1977--above average

Dec 1978--ABOVE average (correction!)

Dec 1982--above average

Dec 1994--below average

Dec 2002--well, we all know how that went!

 

So basically...it works for us every other time. And since it turned out snowy last time...by that trend, this year wouldn't be snowy, unfortunately...of course it could be just coincidental!

EDIT: Missed 1978-79 being good--my bad. So that time we had three good ones in a row!

[frd]

3 minutes ago, Maestrobjwa said:

So basically...it works for us every other time. And since it turned out snowy last time...by that trend, this year wouldn't be snowy, unfortunately...

Thats like saying if you call heads and it comes up tails the next time it will be heads, does not work like that here, and frankly there is more to like than simply those dates.  I am very optimisitc.   

[psuhoffman]

3 minutes ago, Maestrobjwa said:

Seemed to only indicate a snowy winter every other time it happened. So...in chronological order (using BWI totals as I usually do)

Dec 1957-above average

Dec 1958--below average

1962-average winter

1972-below average (strong nino)

1977--above average

1978--below average

1982--above average

1994--below average

2002--well, we all know how that went!

 

So basically...it works for us every other time. And since it turned out snowy last time...by that trend, this year wouldn't be snowy, unfortunately...of course it could be just coincidental!

The Winter that followed December 78 was definitely above average snowfall.  

[Maestrobjwa]

1 minute ago, psuhoffman said:

The Winter that followed December 78 was definitely above average snowfall.  

You're right--somehow my eyes skipped over that as I was looking over the chart, lol

[CAPE]

Last few GFS runs giving some glimpses how the pattern may evolve. Pretty nice h5 look at the end of today's run. Big ridge out west, a stout east based block building into GL, and several of those daughter vortices in N Canada.

[Bob Chill]

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

Last few GFS runs giving some glimpses how the pattern may evolve. Pretty nice h5 look at the end of today's run. Big ridge out west, a stout east based block building into GL, and several of those daughter vortices in N Canada.

12z gefs looking a lot like week 3 of last nights weeklies.... Cautiously optimistic. If the week 4+ pattern starts showing I'm going full weenie. 

[Scraff]

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

Last few GFS runs giving some glimpses how the pattern may evolve. Pretty nice h5 look at the end of today's run. Big ridge out west, a stout east based block building into GL, and several of those daughter vortices in N Canada.

Can we ban the words “daughter vortices”. I have two of them. And damn it if they don’t make my head spin on a constant basis. Let’s go cousin vortices.