Re: Official Long Range Thread 5.0

[Frank_Wx]

Interesting to note: the winter of 77-78, one of my analogs, showed a raging +NAO/AO with a -EPO similar to what current guidance is showing now and still maintined below normal temps. in eastern U.S. Additionally, the MJO then went through a moderate amplitude of phases 4-5-6 which usually correlates to warmer than average temps on east coast. Our current MJO forecast is expected to do the same thing. One key difference though is QBO was in a neutral-positive state

[Frank_Wx]

Euro = snowstorm for 28th 

[Frank_Wx]

Per euro this is basically a surface low that developed on the tail end of a cold front. Whether this is true or not remains to be seen. CMC is not impressed and I threw out both gfs model runs tonight.

[jmanley32]

Oy, I have to drive 80 miles back from CT to here on the 28th, a snowstorm would not be fun to take 95 after the holidays. Of course I want the snow but this puts it at a bad time for moi.

[Frank_Wx]

The 6z GFS shows an H25/160kt jet streak over the central Pac. and moving east. Luckily the EPO ridge is well established by that point, but the flow is still very fast and why you have s/w's digging into the SW Conus at such a high rate. Until the QBO reverses, this will continue to be an issue.

[Frank_Wx]

Along with the jet streak we have a Rex Block developing on the ,odes in the east Pac. That's when there is a low pressure system beneath a dome of high pressure. That will help our -EPO flex

[Frank_Wx]

Pattern change becoming imminent 

[aiannone]

No doubt a push of cold air is coming in the next week, but what concerns me is the length of time that it sticks around. With the pattern staying somewhat progressive and strong shots of pacific energy entering the west, I am concerned that we have this cold around for only a few days and then we are back to above average temps.

[aiannone]

12z GFS Ensemble is very similar to the 12z GFS Operational in the sense that it keeps the cold around for the entire run, with the PV entering as well. Also has a few snow chances down to the coast as well. Winter Cancel Weenies may have to put the white flag back in their pocket for a little while

[Frank_Wx]

Yea Alex I'm not concerning myself with what ha pens after the 8th. Let's try and nail down the storm threats between the 28th and 6th then worry about the pattern.

[Guest]

12z GFS Ensemble is very similar to the 12z GFS Operational in the sense that it keeps the cold around for the entire run, with the PV entering as well. Also has a few snow chances down to the coast as well. Winter Cancel Weenies may have to put the white flag back in their pocket for a little while  

WHAT'S THE QUOTE FROM THE GODFATHER? something like "Just when I thought I was out they suck me back in" or something. That's what you guys are doing to me and I LIKE IT!!

[jmanley32]

FWIW the cmc has a big coastal blow up off the coast around the 31st.

[jmanley32]

Euro has a inland storm 29/30th, wasn;t sure if I should post this here or on 28-29th thread if its the same system or not. Anyways snow is confined north of the coast, hoping that changes, plenty of time to do so way to early to worry about track and exact placement of cold.

[Dunnzoo]

WHAT'S THE QUOTE FROM THE GODFATHER?  something like "Just when I thought I was out they suck me back in" or something.  That's what you guys are doing to me and I LIKE IT!![/quote]


Haha same here... trying to get all my baking done and it's such a distraction!

[sroc4]

Here is Steve D's thoughts from this morning about the winter season thus far (technically its been 2 days).  I have to get my learn on regarding the QBO (Quasi Biennial Oscillation).  Does anyone have any good links regarding the QBO and how it works; influences on the atmosphere etc??

"Let’s dive into the big question of the day, week, and this month.  What the heck happened to winter?

Okay, fair question.  So let’s find out because as you know all the features I have been watching have fallen into place.  There is of course one exception that I actually warned about in the winter forecast.  That one factor that had me concerned was the QBO.

Yesterday in fact, David T. of WXRisk.com and I had a very public chat about this concern and we both had come to the same conclusion.  The QBO was the problem here and this needs to be addressed.  As discussed in the winter forecast, the QBO was an interesting factor.  On one hand, you want a negative QBO.  On the other hand, you don’t want the QBO to be too strong.  My thoughts were that although the QBO was strongly negative, that the QBO would start to weaken to a more moderate level leading to the Polar jet stream over the Pacific to weaken and allow the blocking to take shape.  Otherwise, you have too much of a good thing.  Think of it like having a giant scoop of ice-cream.  Who doesn’t like ice cream?  Right!

However, if you have too much too fast, you get a heck of a headache.  Well, the atmosphere has a head ache and that headache is giving me a headache as well along with indigestion.  Okay, enough with the health stuff.

Look, the key point here is the QBO at 30 MB must weaken and fall steadily.  That happens then the Pacific jet stream weakens, high latitude blocking falls into place because of all the other factors that I have discussed, and everyone is happy.

So here is the good news:

Screen Shot 2014-12-23 at 5.17.50 AM

The numbers above are the QBO values at 30 MB for all of 2014.  The QBO typically peaks in a positive or negative phase every 6 months.  Never in any recorded cases going back to 1950 has the QBO ever constantly increased or decreased for more than 6 months.  Further, there are no cases of the QBO being this strong and then not rapidly weakening there after.  We appeared to have reached that peak back in October at -23.86.  The idea was the QBO would start to weaken in November, which it did, but just not fast enough.  The raw data suggest the QBO is slowly but steadily weakening this month as well, but again not as fast as I had thought it would.  However the trends are such that as the QBO weakens, the high latitude blocking will come and with it the winter pattern I was expecting.  Then you have the +PDO, the Siberian snow influences, the supportive Atlantic SSTA, and a clearly west based El Nino (I’ll discuss tomorrow) all to have an influence for January, February, and March.

So the good news this morning is we know what is wrong and we know that the trends point to more favorable conditions on the way.  Got to love science.  See, if you study the physics and not worry about model output or yearly comparisons, you can quickly find the problem to a forecast and adjust.

As the QBO falls, the Pacific jet streaks will weaken, the MJO will fall into line, and the high latitude blocking starts to set in."

[jmanley32]

Very interesting sroc, do not understand this myself but I guess we need this QBO to drop faster, is there a graph of the projection on that?

[Frank_Wx]

I'll explain QBO to you guys when I get home, or at least doy best

[aiannone]

Happy New Year

Bundle UP

[sroc4]

I'll explain QBO to you guys when I get home, or at least doy best

Frank if you have links to papers or anything that would be awesome too.

[nutleyblizzard]

I'll explain QBO to you guys when I get home, or at least doy best

Frank can you please give us the latest QBO reading? I remember reading at another weatherboard that an optimum number for snow and cold is -10 QBO.

[CPcantmeasuresnow]

Man I was barely starting to grasp the stratospheric warming now I have to know what the QBO is? Does it ever end?

[nutleyblizzard]

Man I was barely starting to grasp the stratospheric warming now I have to know what the QBO is? Does it ever end?

My take on the QBO is that it correlates with the speed of upper level winds. Right now the QBO is too strong, which makes the pattern too progressive. Good news is that the QBO is weakening, just not as fast as forecasters thought.

[nutleyblizzard]

Very encouraging developments with today's Euro and GFS ensemble runs; shows the pattern change occurring at new years timeframe. The Euro shows a PV split by day 10!

[Frank_Wx]

I'll pre-phase this by saying I am also learning more and more about the QBO every day. It is a pretty complex phenomena and one that is not fully understood still. I do know the basics though.

The QBO studies the wind directions in the upper stratosphere. They will either be in an easterly or westerly direction.

Positive QBO = easterlies
Negative QBO = westerlies

A QBO is measured on an index like other signals (NAO, AO, PDO, etc...) so it has values. QBO values between -8 and +8 is considered "neutral" territory. Anything above +8 is positive, vice-versa for negative.

At the beginning of Meteorological winter, the QBO was around -23.00!! That is extremely negative. One thing about an extreme negative QBO (remember, extremes are bad) is that it amplifies the Pacific Jet too much and the Polar Jet remains locked up in Canada. When the QBO goes from a negative state toward a positive one, it means blocking (-NAO) has a good chance of developing because the zonal winds are shifting from west to east.

Remember how I always say the "extreme" is never a good thing for us? For example, when the EPO last season reached extreme negative values, the PV dropped so far south that energy got sheared apart. Hence the dry spell from mid-February into March last year.

Currently, our QBO is -25, which is near record territory and way too negative. This is why the Stratosphere has been so stubborn lately with getting a sudden stratospheric warming event to verify. If it does not begin making its match toward neutral territory soon, the Pacific Jet will end up messing with the PNA out west and the southeast ridge could become a dominant feature this winter.

A lot of people feel the QBO will eventually revert, because it comes in cycles.

DT has the best explanation...read more here

https://www.facebook.com/notes/wxriskcom/another-piece-of-the-winter-2013-14-puzzle-oct-qbo-value-1169/600112926702636

[Frank_Wx]

If you look back at the previous page, you will see I posted the H25 jet streak over the central Pacific and how fast it is. That is one reason why short waves of energy keep digging into the southwest CONUS...the Pac. Jet literally drags them into there. So -PNA = Southeast ridge

[sroc4]

Thanks Frank. I also found Doc Martuccis latest blog. Incredibly informative read on all the major patterns that govern the atmosphere. Oh and if you still want a good winter this will restore your faith. https://doctoochweather.wordpress.com/2014/12/23/winter-cancel-not-by-a-long-shot/

[Frank_Wx]

The period between Dec. 28th and Jan. 7th continues to look like a favorable period to get our first widespread snow accumulation of the season. The 12z EPS is not as bullish as the OP models in bringing the PV so far south, and I also have a hard time believing that too because of the +AO. Last season, the AO was solidly negative in conjunction with the EPO so the PV was dealing with a lot of force. I always preach "extreme" is not good, meaning a signal too negative or too positive will not be very beneficial for us. Take the extreme negative QBO for instance. The Pac. Jet is very fast and taking s/w's and digging them into the SW CONUS. Once the upper Stratosphere zonal winds shift from west to east, we should see the QBO make its march toward neutral territory and finally get some high latitude blocking. LR projections recently are showing the PV at 50 hPa splitting, which if true, could finally help turn things around.

Best thing to do right now is follow the period between the 28th and 7th - it has good potential despite the -PNA/+NAO - then we'll worry about the pattern once we get some more answers.

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