2015-16 Winter Pattern Discussion

[packbacker]

That is exactly the point I was making above.  A warm December is fine.  But the background state of the atmosphere is starting to get worrisome.  As I said the other day, we're going to know some things about January very soon now.

 

People don't look at that...people subscribe to the rubber band theory.  Been lots of scientific papers on that theory, college courses, PHD's on that.

[snowlover91]

Most of the seasonal forecasts I read indicated a warm December. I think we can all pretty much agree with that. But I don't remember reading that the monthly departures would be as warm as they appear they're going to be. Also, I don't recall reading many that suggested the current strong El Nino would be acting as much like a La Nina. I also don't recall anyone forecasting the almost record strong strat PV that is currently in place. So, when we talk about the predictions for a warm December, point taken. But in the context of the current pattern, the calls for a quick flip to winter may turn out to be in a bit of trouble.

One forecaster I read behind did indicate this in his forecast issued October 30th. The forecast showed widespread +2-4F anomalies over our area with >6F anomalies to our north around the Great Lakes area and Northeast. He also showed the cooler anomalies centered around Texas and Nevada which has verified quite nicely. This same forecaster is calling for a flip around January 10th to a much colder pattern across the eastern US. Since it's played out accordingly (still warmer than forecast but pretty close) this gives me confidence for January turning cold, along with signs pointing this way (CFS, weakening PV, UK seasonal, etc).

[Bob Chill]

That is exactly the point I was making above.  A warm December is fine.  But the background state of the atmosphere is starting to get worrisome.  As I said the other day, we're going to know some things about January very soon now.

 

It's definitely worrisome. Persistent and quite strong height anomalies almost always stick around longer than modeled. It does work both ways though. Last year models repeatedly showed the -epo to break down in the long range but it held firm.

 

The general look we are seeing right now is going to really grind on peoples nerves if we are still having this conversation in a month. I'm looking forward to guidance showing the way out without pushing it out in time. My wag is it does happen this winter (just like everyone else is thinking). The when part is tricky of course. 

 

Tonight's weeklies should look pretty awful. At least week 3. 0z run from last night was ugly at the end and that's where the weeklies begin. Weeklies  (weeks 3-4) have been pretty bad so far this fall/winter so it probably doesn't matter much.

[Cold Rain]

People don't look at that...people subscribe to the rubber band theory.  Been lots of scientific papers on that theory, college courses, PHD's on that.

 

The rubber band theory probably has merit, but sometimes they can stretch on far longer than expected.  It may just snap back in April.

 

One forecaster I read behind did indicate this in his forecast issued October 30th. The forecast showed widespread +2-4F anomalies over our area with >6F anomalies to our north around the Great Lakes area and Northeast. He also showed the cooler anomalies centered around Texas and Nevada which has verified quite nicely. This same forecaster is calling for a flip around January 10th to a much colder pattern across the eastern US. Since it's played out accordingly (still warmer than forecast but pretty close) this gives me confidence for January turning cold, along with signs pointing this way (CFS, weakening PV, UK seasonal, etc).

 

Good deal.  Hopefully, that will happen in that time frame.  To me, December is a nice month to have chilly, especially toward the end.  But it's not a big snow month for us.  So, if we're going to waste a month, December is a good one to waste.  On the other hand, I hate the prospect of losing half of January...or more.  The days are short and snow that does pile up can stick around longer.  To me, that is a good thing.

[packbacker]

It's definitely worrisome. Persistent and quite strong height anomalies almost always stick around longer than modeled. It does work both ways though. Last year models repeatedly showed the -epo to break down in the long range but it held firm.

 

The general look we are seeing right now is going to really grind on peoples nerves if we are still having this conversation in a month. I'm looking forward to guidance showing the way out without pushing it out in time. My wag is it does happen this winter (just like everyone else is thinking). The when part is tricky of course. 

 

Tonight's weeklies should look pretty awful. At least week 3. 0z run from last night was ugly at the end and that's where the weeklies begin. Weeklies  (weeks 3-4) have been pretty bad so far this fall/winter so it probably doesn't matter much.

 

Thinking this is the progress we see, or I should say hope to see...it's a start I guess.  Thoughts?

[Jon]

I will say the UKMET seasonal doesn't look too improved but in the realm of mslp, it definitely is. 

 

November forecast for JFM

 

December forecast for JFM

 

-1.5 anomalies over most of the SE, widespread -2 anomalies off the coast of the SE and over FL. Widespread +2 southern Greenland.

[mackerel_sky]

The rubber band theory probably has merit, but sometimes they can stretch on far longer than expected. It may just snap back in April.

Good deal. Hopefully, that will happen in that time frame. To me, December is a nice month to have chilly, especially toward the end. But it's not a big snow month for us. So, if we're going to waste a month, December is a good one to waste. On the other hand, I hate the prospect of losing half of January...or more. The days are short and snow that does pile up can stick around longer. To me, that is a good thing.

Sun angle gets crazy in 9 more days! It's a severe, upward spiral , of concrete-heating. , snow death! Basically the February sun angle is equivalent to Sept- per snowstorm2011!

[snowlover91]

The rubber band theory probably has merit, but sometimes they can stretch on far longer than expected. It may just snap back in April.

Good deal. Hopefully, that will happen in that time frame. To me, December is a nice month to have chilly, especially toward the end. But it's not a big snow month for us. So, if we're going to waste a month, December is a good one to waste. On the other hand, I hate the prospect of losing half of January...or more. The days are short and snow that does pile up can stick around longer. To me, that is a good thing.

Certainly agree! I prefer snow in January since that's the best time here in the south. The rising sun angle in February and longer days makes it melt quicker and cuts down on accumulations to an extent. If I could choose the weather pattern I would have it get cold right in time for thanksgiving, have a white Christmas with 4-6" of snow, then several January threats and a nice ice event or two for February with a quick warmup in spring for severe weather season. Too bad it doesn't work this way! The good news is when we go to the hospital for our baby to be delivered we should have easy driving since it's nice and warm lol.

[griteater]

DonS had a good post last week.  In a nutshell, based on how the AO has progressed, and how it is forecasted to progress in the 2nd half of Dec (per CR's comic chart), the AO is likely to remain positive through Jan, but then likely to be negative in Feb.  Of course, the AO isn't everything.  Can get shutout with it negative, and get a storm with it positive.

 

http://www.americanwx.com/bb/index.php/topic/47332-winter-2015-2016-medium-term-discussion/?p=3786729

[Bob Chill]

Thinking this is the progress we see, or I should say hope to see...it's a start I guess.  Thoughts?

 

I'm not sure what to think to be honest. The way out can come in many forms. And by way out I mean getting away from record heat and not into a winter wonderland...lol. 

 

I suppose the quick and dirty in the near term would have to come in the form of the west ridging out for a time. The anomalous trough cycle out there won't last forever. That could be combined with the very persistent + height anomaly to our n-ne getting pushed northward. Kinda of a quasi -nao so to speak. This would bring us to at least normal temps and not "anti snow". 

 

Of course the 800lb elephant is the ghastly +AO. I'm not sure how we lose that in the next 4 weeks. 

[max100]

How are we even getting this late week "coldwave" (cough)?

[Bevo]

Every December has days in the 70's/80's in the SE (depending on where you live).

 

I guess my confusion is in my probable misunderstanding of El Nino. Wouldn't such a strong EN dictate more SJS interaction, which would also include the warmer/wetter conditions that come with it? I'm pretty confident that I am wrong though.

[griteater]

The other thing is the intense PV, like I said before.  I don't recall seeing any indication that it was expected to be in the state that it's in.

I could be wrong, but I don't think there was any way of knowing that we were going to see a PV of record strength develop until it actually occurred, beginning in November.  Those with access to forecasted wave activity flux charts could have seen the beginnings of it in late Oct.  We aren't, for example, in a period following a big volcanic eruption in the tropics like Pinatubo in the 90's that would favor a +AO.

[packbacker]

I could be wrong, but I don't think there was any way of knowing that we were going to see a PV of record strength develop until it actually occurred, beginning in November.  Those with access to forecasted wave activity flux charts could have seen the beginnings of it in late Oct.  We aren't, for example, in a period following a big volcanic eruption in the tropics like Pinatubo in the 90's that would favor a +AO.

You called me Ji when I brought the w-QBO/solar/SSW issue up in Nov. I had to sprinkle in some weenie false hope posts to not be type casted :-)

[griteater]

You called me Ji when I brought the w-QBO/solar/SSW issue up in Nov. I had to sprinkle in some weenie false hope posts to not be type casted :-)

Ha, yeah, it would be fine to call for a +AO to start, then go with a possible late breakdown due to the +QBO....but I meant that calling for a 'record' strong PV to start would be a tough call to make.

[BullCityWx]

3rd warmest December through yesterday at CLT. Certainly will add greatly to that today. 

[griteater]

From what I read, the MJO shows up on the plots, but the MJO related tropical convection isn't propagating, so it's not a true MJO wave.  Strong ENSO (strong El Nino / strong La Nina) tends to have weak MJO activity.

 

[snowlover91]

Snowiest run yet of the CFS through 45 days.

[Cold Rain]

I could be wrong, but I don't think there was any way of knowing that we were going to see a PV of record strength develop until it actually occurred, beginning in November.  Those with access to forecasted wave activity flux charts could have seen the beginnings of it in late Oct.  We aren't, for example, in a period following a big volcanic eruption in the tropics like Pinatubo in the 90's that would favor a +AO.

 

Exactly...which is why I'm becoming more concerned about the expected flip by mid-Jan.  If we just had El Nino being El Nino, then sure, but this monster PV is a real problem that wasn't generally expected to this degree when some of these mid-winter pattern-flip forecasts were made.

[Cold Rain]

^^ How does the CFS come up with all of that snow amidst it's horrendous pattern progs?

[snowlover91]

^^ How does the CFS come up with all of that snow amidst it's horrendous pattern progs?

Looking through its 500mb anomalies, by D20 it's moving the ridge north into western and central Canada with a trough that develops near Texas and encompasses from there to northern Florida. Three out of the 4 members show this and by late January shows widespread anomalies across the central and eastern areas of the country. Another image below shows two possible outcomes for January.

[Cold Rain]

^ Good deal.  That is the right progression that we want to see.  If we see that, we'll be in business...especially if the STJ ever kicks in.

[snowlover91]

^ Good deal.  That is the right progression that we want to see.  If we see that, we'll be in business...especially if the STJ ever kicks in.

The key to watch for is strong ringing to develop over AK and western Canada region. Analogs favor this unfolding around January 6-10th, until then it will be much like we are seeing now; a torch. I expect one or two strong storms to change the pattern for us in this timeframe and set the stage for a much better pattern favoring mid January through late February here in the south.

[SnowNiner]

Exactly...which is why I'm becoming more concerned about the expected flip by mid-Jan.  If we just had El Nino being El Nino, then sure, but this monster PV is a real problem that wasn't generally expected to this degree when some of these mid-winter pattern-flip forecasts were made.

 

Yes.  Warm December and cold January and February analogs have been mainly based on nino from what I've read (and the QBO).  When you get a massive +AO and a HOT December, you can't claim victory based on those analogs and think Jan and Feb will still flip the switch.  Add to the discussion the "variables"(that I don't understand) causing forcing that creates nina like conditions and a pseudo-MJO response, who in the world knows what's going to happen the next month or two.  Frankly I wouldn't be surprised by anything at this point. 

 

Maybe the best thing in our favor is the rubber band theory....we've been in a neutral to positive AO state since mid October.  You'd think by mid January (4 months), you'd get the relaxation we need.

[No snow for you]

Is JB going to be right? Also somebody may be buying lunch and changing his handle if the CFS is right. 

[deltadog03]

This is GOLD right now...LOL  y'all have been talking about the CFSv2 and its been showing wall to wall warm, but now the latest runs are flipping to a more normal to potentially below normal pattern by the beginning of JAN or so.  Its following the JMA, CMC and the EURO (along with WXB model and JB)  Below is week 2, 3 and 4 precip and days 11-15, 16-20 and 21-25 at 500mb.  Notice the mean ridge starting to build NW....and the jet really undercutting into the southern plains and nosing into the SE.  That is the start of the true winter pattern IMHO....that will mean the nino can drive the pattern....The nino is NOT driving it right now imho.  

[mackerel_sky]

Is JB going to be right? Also somebody may be buying lunch and changing his handle if the CFS is right.

JB hugs the cfs every year! I'll stand by my word!

[deltadog03]

He has NOT hugged it this year...He has been super against it util now.  He noticed how it has done the best so far with DEC.

[Cold Rain]

It is encouraging to see the CFS turn around.  If that trend continues, then that's definitely a good sign and a reason to be optimistic.

[snowlover91]

Yes.  Warm December and cold January and February analogs have been mainly based on nino from what I've read (and the QBO).  When you get a massive +AO and a HOT December, you can't claim victory based on those analogs and think Jan and Feb will still flip the switch.  Add to the discussion the "variables"(that I don't understand) causing forcing that creates nina like conditions and a pseudo-MJO response, who in the world knows what's going to happen the next month or two.  Frankly I wouldn't be surprised by anything at this point. 

 

Maybe the best thing in our favor is the rubber band theory....we've been in a neutral to positive AO state since mid October.  You'd think by mid January (4 months), you'd get the relaxation we need.

Imo the switch will come January 6-10th with the cold pattern setting up at that time. Until then I expect the same type of warm weather like we've been seeing to continue even into the first few days of January. Analogs were quite useful since they showed the idea of a well above normal December. We've seen this just to a greater magnitude due to a combination of factors and the analogs suggested the overall pattern of cool west vs warm east. This flips in January with a warm west vs cold east pattern setting up, especially along the southern states. We will know in a few weeks if these analogs end up being correct, with so much data pointing to a flip early January, I think the chance is quite high.