January Pattern and Storm Discussion II

[Tacoma]

Looks marginal to me.  GFS not very gung-ho either.  Event should be completely over by Super Bowl time.  If we do get snow, it would be late Saturday into early Sunday.  It's a quick mover, which will also limit QPF.

 

why is it when we do have a little something to watch or actually a storm comes in it seems to be a fast moving storm?  what does it take to get a slow moving storm or to get these systems to slow down,  move slowly thru.

[Southern Track]

Not much to lift hopes right now. I look at the indicies every day. As I stated yesterday not sure they're a good tool in the long range.

But today the Ensemble mean outlook has:

PNA - Slightly positive throughout the next couple of weeks (not bad for stopping the Pacific air invasions)

NAO - Positive throughout the next couple of weeks (bad because cold will be transient)

AO - Definitly positive the first week, then all over the place. Maybe averaging neutral (not a lot of cross-polar air)

So maybe for the next couple of weeks we have transient shots of stale Canadian air masses. Like what the GFS is currently showing.

So the MJO pulse looks to settle in Phase 8 for the time being. I thought it carried more weight in terms of a determining a pattern?

[tnweathernut]

So the MJO pulse looks to settle in Phase 8 for the time being. I thought it carried more weight in terms of a determining a pattern?

 

It would be nice if the MJO pulse can get into phase 1 and/or 2.  Those phases in February tend to be more robust with precipitation in the southeast and colder in temps.  Phase 8 tends to be cold, but fairly dry at the same time.

[Isopycnic]

That has been the pattern all winter. Warm and rain, then gets cold, then warms up and rains again. Rinse and repeat.

 

This reminds me of the usual and typical weather pattern for NC.

[Southern Track]

It would be nice if the MJO pulse can get into phase 1 and/or 2. Those phases in February tend to be more robust with precipitation in the southeast and colder in temps. Phase 8 tends to be cold, but fairly dry at the same time.

Okay I see that, thanks. Phase 1 has a cold look with a gulf type precipitation look as well.

[franklin NCwx]

It would be nice if the MJO pulse can get into phase 1 and/or 2.  Those phases in February tend to be more robust with precipitation in the southeast and colder in temps.  Phase 8 tends to be cold, but fairly dry at the same time.

You are correct. I asked this question yesterday why all the ensemble guidance takes the mjo into phases 8,1,2 yet they also have turned warm starting next week. For the last couple of days, the euro ensembles have looked horrible in the longer range after a cool down this week.

[Tacoma]

It would be nice if the MJO pulse can get into phase 1 and/or 2.  Those phases in February tend to be more robust with precipitation in the southeast and colder in temps.  Phase 8 tends to be cold, but fairly dry at the same time.

haven't I been reading in the past week that we are headed and most likely going into phase 1 and maybe 2?

[franklin NCwx]

From yesterday's CPC mjo update. . http://www.cpc.ncep....O/mjoupdate.pdf      

 

 

　

Other forms of subseasonal variability remain active and have contributed to making the MJO signal less clear. This is expected to be temporary and dynamical model MJO index forecasts are in good agreement of renewed eastward propagation during the period.

 

 

　

For the U.S., the MJO favors, on average, split flow and ridging across the western U.S. and a mean trough across the east until about mid-February. The MJO would also favor an active southern jet during this similar period. Thereafter, the MJO would support a tendency for a mean trough to develop across the western U.S. near the last week of February.

[SnowNiner]

From yesterday's CPC mjo update. . http://www.cpc.ncep....O/mjoupdate.pdf      

 

 

　

Other forms of subseasonal variability remain active and have contributed to making the MJO signal less clear. This is expected to be temporary and dynamical model MJO index forecasts are in good agreement of renewed eastward propagation during the period.

 

 

　

For the U.S., the MJO favors, on average, split flow and ridging across the western U.S. and a mean trough across the east until about mid-February. The MJO would also favor an active southern jet during this similar period. Thereafter, the MJO would support a tendency for a mean trough to develop across the western U.S. near the last week of February.

 

This seems to be our only hope in keeping a winter pattern; the MJO in favorable phases for the next 2 weeks or so.  Without blocking though I don't know if we'll get a storm track that stays south of us.  If we could just get a -NAO to go with our ridging we'd be set.  Clocks tickin.  I think we're done though after 2/15.  Birds are already active in the morning and my daises are coming up.  Seems to get earlier every year. 

[GaWx]

You are correct. I asked this question yesterday why all the ensemble guidance takes the mjo into phases 8,1,2 yet they also have turned warm starting next week. For the last couple of days, the euro ensembles have looked horrible in the longer range after a cool down this week.

 

 The best answer is that the MJO phases' effects on our wx are not nearly so black and white as some seem to think. The MJO is a tool, not a crystal ball. There are some tendencies with each phase represented by the maps showing averages, but the actual wx can be all over the place. Those maps show the averages of a whole bunch of varying scenarios. Heck, you can get a major cold wave and/or big SE winter storm when the MJO is in its less favorable phases. Great example: Dec. of 2010, which was very cold in the SE US, was in phases 3-5 and within the circle (the preceding late Nov, was also within the circle) throughout the month! But how could that possibly be? Because it isn't black and white...that's why. For one thing, a lot depends on other things like the NAO, AO, PDO/PNA, AMO. etc. as well as unknown factors as well as randomness.Then there's also the lag factor that makes it even less clear.

[DaculaWeather]

And NOTHING this year has been black and white. 

[ncwinterwxman]

What makes you think that late Feb/early Mar could be the best part of winter?  If you have already explained this, please forgive me. 

 

Edit:  My own thoughts were that if we don't get something between now and the second or third week of February, we aren't going to see anything due to the MJO heading into unfavorable territory and the lack of any kind of blocking that we have seen this winter strengthens this argument.  In addition, the EPO, NAO, and PNA look very lackluster to help us over the next 10 days...

 That's why I would never want to move up north. I would never want to live where 3-6" of snow is nothing special due to its frequency. The novelty ofsnow is taken away. I love living where snow is rare enough to make just 1-2" a pretty big deal.

 

 Anyway, I'm educatedly guessing there will be a rather uneventful next three weeks or so for much of the SE at least outside of NC/TN followed by what could easily be the best part of the winter sometine during the subsequent three weeks. We'll see.

[LithiaWx]

And NOTHING this year has been black and white.

The only constant has been a crap pacific screwing us over and over again.

[Bevo]

The only constant has been a crap pacific screwing us over and over again.

 

In my opinion, that's the common denominator that answers many questions regarding the last two winters.

[GaWx]

What makes you think that late Feb/early Mar could be the best part of winter?  If you have already explained this, please forgive me. 

 

 Analog Non-El Nino winters when both Dec. and Jan. were quite warm relative to normal in Atlanta and with the coldest low temperatures being relatively high. As I always like to remind folks and just did about the MJO, nothing is black and white with wx predictions...but there are tools to help look for tendencies. The tendency for these types of Dec./Jan.'s has been to be mild in most of early to mid Feb. but to also have a backloaded winter rather than having warmth til the end and an early ending. Yes, of course, it could turn out to be warm in late Feb. and March. However, the tendencies of the analogs say probably not. If you want more details on what is getting me to be optimistic about late winter, please go to this thread I created on January 1st (it started as a warm Dec. analog related thread) to discuss this:

 

 http://www.americanwx.com/bb/index.php/topic/38633-rest-of-se-winter-best-by-far-yet-to-come-per-warm-dec-analogs/

 

 Note my mention that the warm Dec. analogs favored both a mild/warm Jan. and a heightened chance for a major ice storm around late Jan. Jan. did turn out to be mild to warm. Also, whereas there was no major ZR and no ZR at all in Atlanta, there was a minor to moderate ZR on 1/25 in much of NC, upstate SC, and NE GA and the worst one in several years for many. I'd say the analog based predictions did pretty well there. If the analogs continue to have predictive power, things would be looking up for early to mid March and possibly as early as late Feb.

[HurricaneTracker]

why is it when we do have a little something to watch or actually a storm comes in it seems to be a fast moving storm?  what does it take to get a slow moving storm or to get these systems to slow down,  move slowly thru.

 

Well, for one, this system on Saturday night is more of an Alberta Clipper type system.  They originate in Alberta Canada and quickly move southeast on strong northwest flow aloft.  That's just their nature.  All clippers pretty much work the same way and are fast moving.  In the Midwest, they can be expected to bring 1-3" of snow most occasions.  Down here, 0-1" is normal in the mountains.  Downslope winds often limit precip east of the mountains.

 

Tough to get a slow moving snow storm in winter in general, owing to fast westerlies aloft.  But, it can happen if you align the system with the upper level trough and offer some sort of semi-blocking feature downstream to slow the progression of the trough.  That's what brought us our massive rains earlier this month.

[SnowNiner]

The only constant has been a crap pacific screwing us over and over again.

Trying to understand this, what exactly has been wrong with the pacific that has caused so much trouble?  We've had a west coast ridge on occasion, there's been a -EPO if I'm not mistaken.  What's been the issue?  Was it a lack of southern stream jet?  Why has that been the case?  Thanks. 

[GaWx]

Edit:  My own thoughts were that if we don't get something between now and the second or third week of February, we aren't going to see anything due to the MJO heading into unfavorable territory and the lack of any kind of blocking that we have seen this winter strengthens this argument.  In addition, the EPO, NAO, and PNA look very lackluster to help us over the next 10 days...

 

1)  Be careful how much importance you place on the MJO phases. Just as you don't see why it isn't looking cold just ahead with the favorable MJO phases, maybe it will get cold during the next go round of the unfavorable ones. Who's to say it can't or won't? Think about Dec. 2010, which was within the unfavorable phases 3-5 and within the circle rather than phases 7/8/1, and was during a very strongly negative PNA of all things! So, you never know. Of course, it did have blocking on its side.

 

2) The MJO forecasts could turn out to be wrong as they often are. Maybe it will head into the circle or do something else not predicted?? Also, there's no telling where it will be in late Feb. to mid March. It is essentially pretty unpredictable a month+ out. It isn't even all that well predicted two weeks out a lot of times!

 

3) Even if the models are right about the PNA/EPO/NAO/AO being unfavorable over the next two weeks or so, that doesn't tell us how they'll be in late Feb. to March. Actually, I'm favoring a mild early to mid-Feb. So, I would actually expect the PNA/EPO/NAO/AO to not be favorable for the next  2-3 weeks overall.

 

4) The warm Dec.-Jan. analogs, as I mentioned, suggest things aren't looking up for early to mid Feb. However, those same analogs say to look for a change in either late Feb. or especially early March.

[franklin NCwx]

 The best answer is that the MJO phases' effects on our wx are not nearly so black and white as some seem to think. The MJO is a tool, not a crystal ball. There are some tendencies with each phase represented by the maps showing averages, but the actual wx can be all over the place. Those maps show the averages of a whole bunch of varying scenarios. Heck, you can get a major cold wave and/or big SE winter storm when the MJO is in its less favorable phases. Great example: Dec. of 2010, which was very cold in the SE US, was in phases 3-5 and within the circle (the preceding late Nov, was also within the circle) throughout the month! But how could that possibly be? Because it isn't black and white...that's why. For one thing, a lot depends on other things like the NAO, AO, PDO/PNA, AMO. etc. as well as unknown factors as well as randomness.Then there's also the lag factor that makes it even less clear.

Thanks for the response Larry. Both the favorable mjo phases and the warm temps showing up could flip in the next couple days. Both are still in "model world" and both could be wrong. But, I thought the mjo was a bigger driver of the pattern compared to others? I remember Dec2010 being a -pna it also had an off the charts-nao. I did not remember the mjo phases so thanks for stats.

[Southern Track]

Can't post Pro.accuweather, but GFS showing potential CAD event at 162.

[GaWx]

Thanks for the response Larry. Both the favorable mjo phases and the warm temps showing up could flip in the next couple days. Both are still in "model world" and both could be wrong. But, I thought the mjo was a bigger driver of the pattern compared to others? I remember Dec2010 being a -pna it also had an off the charts-nao. I did not remember the mjo phases so thanks for stats.

 

You're welcome. I didn't remember the MJO phases from Dec. 2010, myself. I get them from here (going back to the 1970's):

 

 http://www.bom.gov.au/climate/mjo/

 

If one wants to best appreciate that the correlation between 7/8/1 and SE cold as well as between 3/4/5/6 and SE warmth isn't as high as some seem to think, just go through here and click on a bunch of past winters. You'll see many exceptions to these guidlelines. The atmosphere is way too complicated to allow SE US wx to correlate too strongly with the MJO phases.

[Cold Rain]

IMO, with so much energy in the northern stream, we're going to need blocking if we're going to overcome the non-favorable alignment of indexes like the PNA, MJO, etc. I agree with Larry in that the MJO is just a piece of the puzzle and is not black and white. But as we move on into Feb and the MJO travels into less favorable phases, we will need to have something to counter it, if we expect to be cold and stormy.

The energy in the northern stream beats down the PNA. So I believe we are going to see a healthy Greenland block set up if we are to have any sort of sustained good pattern for winter weather, once the MJO goes into the bad phases. I have seen no evidence of any Greenland blocking or any sustained west-based NAO all winter. That doesn't mean it won't change tomorrow, but there doesn't appear to be any evidence of it anytime soon either.

That brings us back to threading a really small needle. It could happen. But regardless of analogues or other historical data, the evidence presenting itself to me right now, today, does not show me anything that looks anything like a cold end to winter. I hope I'm way off on this.

[Cold Rain]

Can't post Pro.accuweather, but GFS showing potential CAD event at 162.

The 12Z? It looks to me, at 162, to show a Low moving through PA, jumping to the mid Atlantic coast bringing a front to the SE. I don't see any HP except a couple of 1020s north of the boarder. Then comes the warm up.

[tnweathernut]

IMO, with so much energy in the northern stream, we're going to need blocking if we're going to overcome the non-favorable alignment of indexes like the PNA, MJO, etc. I agree with Larry in that the MJO is just a piece of the puzzle and is not black and white. But as we move on into Feb and the MJO travels into less favorable phases, we will need to have something to counter it, if we expect to be cold and stormy.

The energy in the northern stream beats down the PNA. So I believe we are going to see a healthy Greenland block set up if we are to have any sort of sustained good pattern for winter weather, once the MJO goes into the bad phases. I have seen no evidence of any Greenland blocking or any sustained west-based NAO all winter. That doesn't mean it won't change tomorrow, but there doesn't appear to be any evidence of it anytime soon either.

That brings us back to threading a really small needle. It could happen. But regardless of analogues or other historical data, the evidence presenting itself to me right now, today, does not show me anything that looks anything like a cold end to winter. I hope I'm way off on this.

 

 

I just glanced at the major model runs from last night and I thought I saw blocking trying to set up toward the end of the runs on the ensembles. 

 

I guess I am in the minority here (maybe senile or overly optimistic), but I think our next shot at "potential" comes in the Feb 10th-20th timeframe.  Looks to me like split flow develops and if we can manage some blocking I think there is a real chance at something popping up during that timeframe.

[Southern Track]

The 12Z? It looks to me, at 162, to show a Low moving through PA, jumping to the mid Atlantic coast bringing a front to the SE. I don't see any HP except a couple of 1020s north of the boarder. Then comes the warm up.

I gotcha. Wasn't too sure of placement of HP or if it was there at all.

[packbacker]

The 12Z? It looks to me, at 162, to show a Low moving through PA, jumping to the mid Atlantic coast bringing a front to the SE. I don't see any HP except a couple of 1020s north of the boarder. Then comes the warm up.

 

Yeah, it looked similar to last Friday's storm, northern stream energy digging and pops a low off the VA coast, we would obviously need it to dig a lot further south.

[Cold Rain]

I gotcha. Wasn't too sure of placement of HP or if it was there at all.

If we could get that whole business to move south a good deal, we'd have a shot. Who knows.

[Cold Rain]

I just glanced at the major model runs from last night and I thought I saw blocking trying to set up toward the end of the runs on the ensembles.

I guess I am in the minority here (maybe senile or overly optimistic), but I think our next shot at "potential" comes in the Feb 10th-20th timeframe. Looks to me like split flow develops and if we can manage some blocking I think there is a real chance at something popping up during that timeframe.

I have observed the same thing in the LR all season. The models seem to show a -NAO in the LR and then it is either too transient or becomes east-based, neither of which offer much help. I tend to put more weight on trends, until they change or until there is really strong evidence the other way. But I'm with you in the end....I think we get another shot or two. I am just skeptical of a sustained good pattern anytime soon.

[Southern Track]

If we could get that whole business to move south a good deal, we'd have a shot. Who knows.

I agree. I guess we need to get by tomorrow with our structures intact before we look ahead.

[FallsLake]

If we could get that whole business to move south a good deal, we'd have a shot. Who knows.

We have seen systems trend south on the models a number of times this year. This setup looks strange in the since that the low looks to cut off over Ohio and then slowly move east from that point. There is a high to the north that does block its movement. This high could eventually help us in keeping the system more south. (but) I think we have at least a few changes to this look in the next couple of days.