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AMZ8990

Winter Speculation 2018/19

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Rain, sleet, snow, thunderstorms, regional climate, jet stream, La Niña, El Niño, polar vortex, ice pack, ETC.  anything that can have an affect on the two seasons in question is up for analysis and debate.  Our forum is one of the best at informing and teaching people as well as conversing with friends.  Let’s try to keep that going with this thread, and don’t forget a lot of people come to our threads just to learn.  As we have some very talented professional and novice Mets on our board.  Let the speculation begin!

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North Pacific Hadley Cell being stretched north through most of July.. I think this rubber bands to a +PNA in the Winter. 

ENSO Neutral but may favor +PNA because of wave cycles of the last few years. 

Atlantic SSTs are -NAO in coming Winter and some other things like +precip in May Southeast/TN Valley support Winter -NAO

I would go below average and snowy. :)

 

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Thanks for the thread, Jax...I waffle back and forth like crazy on this.  I lean weak Nino climo...but if that does not happen then all bets are off.  So, precip slightly above...temps normal...no idea on snow.  Patterns are such a crap shoot for snow....  Last winter was a great example.  Incredible cold and basically a mini-drought due to a RAGING -EPO.  Snow is a timing thing.  Nina patterns often result in poor timing because the patterns are just dry...not enough times at the plate to grab a baseball analogy.  Nino patterns are often rainy, but give you plenty of more chances for snow because when the cold does come in its less extreme form...you have a real chance.  I like weak Nina's just because they can be really cold.  Weak Ninos are the money pattern for snow...still not sold that happens this winter but believing it to be of slightly higher likelihood than not.

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Euro monthlies rundown follows, verbatim with little (serious) commentary. Charts came out last week.

July looks hot. What's new? August and September have a reasonable look, seasonably warm but not a bad whipping compared to July. Aug-Sept is believable if El Nino can start to influence.

October, November, and December show trough west ridge east. Tee up severe weather! Actually, probably not. Who believes shoulder month forecasts? Mild December makes sense if El Nino but October and November are notoriously fickle and variable.

January is shown colder than normal. Typical El Nino winters feature a turn colder at some point. Recent Nino cases have been second half of January. Like others above, six months out I will punt forecasting precip. 

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On 7/10/2018 at 12:03 AM, jaxjagman said:

Not horrid looking anyways,right now

NMME_ensemble_tmp2m_us_season5 png  800×618 .png

And if Nino climo is in play...December would be warm w January and February being cold which "might" mean that January and February are seasonal to slightly BN which is plenty good here.  But yeah, I would take that map with the caveat that cold source regions look pretty "iffy."  The seasonal temps are likely due to seasonal or AN precip.  Still, better than trying to get it to snow during a prolonged drought.

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On 7/9/2018 at 11:52 AM, nrgjeff said:

Euro monthlies rundown follows, verbatim with little (serious) commentary. Charts came out last week.

July looks hot. What's new? August and September have a reasonable look, seasonably warm but not a bad whipping compared to July. Aug-Sept is believable if El Nino can start to influence.

October, November, and December show trough west ridge east. Tee up severe weather! Actually, probably not. Who believes shoulder month forecasts? Mild December makes sense if El Nino but October and November are notoriously fickle and variable.

January is shown colder than normal. Typical El Nino winters feature a turn colder at some point. Recent Nino cases have been second half of January. Like others above, six months out I will punt forecasting precip. 

Thanks for the great info.  Seems like a logical sequence qiven the pattern progression.  Waiting on those "second half" winters is brutal around the forum.   LOL.  Lots of cliff jumping predicted.  Maybe Mother Nature will throw us a bone early just to break-up the monotony.  That said, if the Nino is weak, sometimes things can get rolling in early January.  Hopefully we don't see any ultra-early snows...those seem to be bad, bad mojo for MBY.  

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Looking at the latest solar predictions this could be even more like the 2009-2010 winter.With a developing ElNino,like during the 2009-2010 winter we had our coldest winter here in over 30 years during this time in Nashville.If it happens or not we'll see.What's interesting to me is the Quasi-biennial Oscillation (QBO) is at record proportion for the month of June -28.45,though this most certainly will change,it's never been this strongly negative this time of year

Solar Cycle Progression   NOAA   NWS Space Weather Prediction Center.png

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12 hours ago, jaxjagman said:

Looking at the latest solar predictions this could be even more like the 2009-2010 winter.With a developing ElNino,like during the 2009-2010 winter we had our coldest winter here in over 30 years during this time in Nashville.If it happens or not we'll see.What's interesting to me is the Quasi-biennial Oscillation (QBO) is at record proportion for the month of June -28.45,though this most certainly will change,it's never been this strongly negative this time of year

Solar Cycle Progression   NOAA   NWS Space Weather Prediction Center.png

Interesting 

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In reply to Carvers post in the spring/summer pattern thread about El Nino being back loaded. I've seen both front loaded and back loaded.  2009-2010 started fast and furious and never let up until late February.  

A couple years ago it was super back loaded and we got bombed in February. 

Here are some of our Nino Decembers.

Early December of 1957 it snowed 3 inches and got to -7 degrees then warmed up later in the month. Strong Nino

December of 1958 it was frigid, around 5 degrees below normal for the month, lots of lows in the 10s, snowed just over 2 inches for the month. Very dry with only 1.5 inches of rain total.

December of 1963 it was super cold for December. 8 days in the single digits for lows, peaking down at -5 on 12-19. It snowed on 14 days of the month, the last 10 days were pure winter. 7 inches of snow on 12-22, 8 inches on 12-23, 7 inches on 12-31.

December of 1965 it was a drought. It was average to above on temps. Snowed a couple of times, December 1st it was 9 degrees.  Less than 1 inch of rain for the month. Strong Nino

December of 1968 it was below normal on temps, snowed on 8 days, 2 inches was the biggest event on 12-4-68. 10 days with lows in the 10s, highest temp was 57. Coldest day was 24/13 with snowshowers on 12-15-68.

December of 1969, which was a weak Nino, was cold with a huge snow event on Christmas day with 8 inches falling. Snow fell on 13 days of the month. 

December of 1972 was a torch, around 5 degrees above normal for the month. There were still a few cold/snow showery days but overall wet with 10 inches of rain, and warm.

December of 1976 was cold, snowed on 5 different days, snowed 2 inches on 12-21, snowed an inch on the 29th, the temp shot p to 50 and it changed to rain on the 30th, but it switched back to snow and snowed 1.5 inches on the backside of the system. 12-31 was the coldest day at 23-2.

December of 1977 was about 2 degrees below average overall and it snowed on 10 different days. None were more than .5 inches though. 

December of 1979 was mild, 2 degrees above average but snow fell on 4 different days of the month, also less than .5 inches each event. This was a weak Nino and it's a rareish one that was above normal in December.

December of 1982 was very warm, around 6 degrees above normal with 8 inches of rain. We had a 5 inch snow during the month though. Very strong Nino.

December of 1986 had a few days of snowshowery weather and was around 1 degree below normal overall for the month. 

This general pattern continues, if the Nino is strong or very strong, December is probably going to be AN and either very wet or very dry. If the Nino is weak or moderate, it's often game on in December, but not always.

 

 

 

 

 

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9 hours ago, John1122 said:

In reply to Carvers post in the spring/summer pattern thread about El Nino being back loaded. I've seen both front loaded and back loaded.  2009-2010 started fast and furious and never let up until late February.  

A couple years ago it was super back loaded and we got bombed in February. 

Here are some of our Nino Decembers.

Early December of 1957 it snowed 3 inches and got to -7 degrees then warmed up later in the month. Strong Nino

December of 1958 it was frigid, around 5 degrees below normal for the month, lots of lows in the 10s, snowed just over 2 inches for the month. Very dry with only 1.5 inches of rain total.

December of 1963 it was super cold for December. 8 days in the single digits for lows, peaking down at -5 on 12-19. It snowed on 14 days of the month, the last 10 days were pure winter. 7 inches of snow on 12-22, 8 inches on 12-23, 7 inches on 12-31.

December of 1965 it was a drought. It was average to above on temps. Snowed a couple of times, December 1st it was 9 degrees.  Less than 1 inch of rain for the month. Strong Nino

December of 1968 it was below normal on temps, snowed on 8 days, 2 inches was the biggest event on 12-4-68. 10 days with lows in the 10s, highest temp was 57. Coldest day was 24/13 with snowshowers on 12-15-68.

December of 1969, which was a weak Nino, was cold with a huge snow event on Christmas day with 8 inches falling. Snow fell on 13 days of the month. 

December of 1972 was a torch, around 5 degrees above normal for the month. There were still a few cold/snow showery days but overall wet with 10 inches of rain, and warm.

December of 1976 was cold, snowed on 5 different days, snowed 2 inches on 12-21, snowed an inch on the 29th, the temp shot p to 50 and it changed to rain on the 30th, but it switched back to snow and snowed 1.5 inches on the backside of the system. 12-31 was the coldest day at 23-2.

December of 1977 was about 2 degrees below average overall and it snowed on 10 different days. None were more than .5 inches though. 

December of 1979 was mild, 2 degrees above average but snow fell on 4 different days of the month, also less than .5 inches each event. This was a weak Nino and it's a rareish one that was above normal in December.

December of 1982 was very warm, around 6 degrees above normal with 8 inches of rain. We had a 5 inch snow during the month though. Very strong Nino.

December of 1986 had a few days of snowshowery weather and was around 1 degree below normal overall for the month. 

This general pattern continues, if the Nino is strong or very strong, December is probably going to be AN and either very wet or very dry. If the Nino is weak or moderate, it's often game on in December, but not always.

 

 

 

 

 

As always, great post and thanks for working that conversation back into the correct thread.  Great information and will read again.  Those records are uncorrupted and a fantastic resource for the board.  I am going w a weak to low-end moderate El Nino...just a hunch.  Maybe it even falters a bit.  I would be surprised by a strong-moderate or strong Nino.  Maybe we get going early based on your numbers.  My gut really wants to start this winter right after Christmas and then go right to the end of February...w a typical January thaw embedded.  I suspect December will have some cold, but it seems sometimes that the warm numbers are just difficult to overcome these days. I can envision a scenario where December begins warm, and then it is just a matter of whether it can get cold enough to average things out - but I am way off in hypothetical land w that.  I am encouraged by the recent rains.  We need to break the pattern of long dry spells in NE TN.  We have been getting rain w some long dry spells in between.  IMHO, for a good winter we need frequent precip chances.  

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Sun and QBO are flashing cold signals for winter. I still like 2008-09 for the solar cycle comparison, which was a somewhat cold winter. QBO has been acting strange/erratic for about 3 years now; we need it to stay down for cold. 

Solar activity is down at 2009 levels (09-10 winter) and cosmic rays are even more telling. More of them get into the atmo when the sun is not playing defense (right now). Those data all by themselves would point sharply colder like 09/10/11. However we are coming off a warm hang-over; so, I still like 07/08/09. Also the Arctic source region is forecast warm.

The other note is that sunspot mins do not always come with big time blocking. It has failed several times. In fact Anthony M. tweeted stats in the range of only 50/50 success (all years). However this year we have QBO and El Nino going for winter.

Yeah I doubt we get Super Nino or even strong. I'm thinking weak to low-end moderate. Really (all by itself) that's about as good as it gets from ENSO. Managing expectations though. It's the South, lol.

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On 8/2/2018 at 1:57 PM, John1122 said:

In reply to Carvers post in the spring/summer pattern thread about El Nino being back loaded. I've seen both front loaded and back loaded.  2009-2010 started fast and furious and never let up until late February.  

A couple years ago it was super back loaded and we got bombed in February. 

Here are some of our Nino Decembers.

Early December of 1957 it snowed 3 inches and got to -7 degrees then warmed up later in the month. Strong Nino

December of 1958 it was frigid, around 5 degrees below normal for the month, lots of lows in the 10s, snowed just over 2 inches for the month. Very dry with only 1.5 inches of rain total.

December of 1963 it was super cold for December. 8 days in the single digits for lows, peaking down at -5 on 12-19. It snowed on 14 days of the month, the last 10 days were pure winter. 7 inches of snow on 12-22, 8 inches on 12-23, 7 inches on 12-31.

December of 1965 it was a drought. It was average to above on temps. Snowed a couple of times, December 1st it was 9 degrees.  Less than 1 inch of rain for the month. Strong Nino

December of 1968 it was below normal on temps, snowed on 8 days, 2 inches was the biggest event on 12-4-68. 10 days with lows in the 10s, highest temp was 57. Coldest day was 24/13 with snowshowers on 12-15-68.

December of 1969, which was a weak Nino, was cold with a huge snow event on Christmas day with 8 inches falling. Snow fell on 13 days of the month. 

December of 1972 was a torch, around 5 degrees above normal for the month. There were still a few cold/snow showery days but overall wet with 10 inches of rain, and warm.

December of 1976 was cold, snowed on 5 different days, snowed 2 inches on 12-21, snowed an inch on the 29th, the temp shot p to 50 and it changed to rain on the 30th, but it switched back to snow and snowed 1.5 inches on the backside of the system. 12-31 was the coldest day at 23-2.

December of 1977 was about 2 degrees below average overall and it snowed on 10 different days. None were more than .5 inches though. 

December of 1979 was mild, 2 degrees above average but snow fell on 4 different days of the month, also less than .5 inches each event. This was a weak Nino and it's a rareish one that was above normal in December.

December of 1982 was very warm, around 6 degrees above normal with 8 inches of rain. We had a 5 inch snow during the month though. Very strong Nino.

December of 1986 had a few days of snowshowery weather and was around 1 degree below normal overall for the month. 

This general pattern continues, if the Nino is strong or very strong, December is probably going to be AN and either very wet or very dry. If the Nino is weak or moderate, it's often game on in December, but not always.

 

 

 

 

 

Speaking of 2010,this was the year the bowling ball came through.

http://origin.wpc.ncep.noaa.gov/winter_storm_summaries/graphics/2009_2010/jan28_30_2010.html

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4 hours ago, jaxjagman said:

Speaking of 2010,this was the year the bowling ball came through.

http://origin.wpc.ncep.noaa.gov/winter_storm_summaries/graphics/2009_2010/jan28_30_2010.html

That was a great event for the whole state basically. I was lucky enough to stay all snow and ended up with 13 inches. I believe the central valley and central plateau of East Tennessee had some major mixing issues with freezing rain and sleet.

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QBO broke another record for July like June coming in at -29.10,this is back to back record months for this year.The most negative in any month on ESRL shows was back into Nov.2005 when it reached -29.55 so this month of July ranks 2nd all-time

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30 minutes ago, jaxjagman said:

QBO broke another record for July like June coming in at -29.10,this is back to back record months for this year.The most negative in any month on ESRL shows was back into Nov.2005 when it reached -29.55 so this month of July ranks 2nd all-time

It seems when the QBO is this negative going into August, it almost always stays negative into November (which can be a fair indicator in a winter weather forecast). Fingers crossed we don't have another 1994-95 or 2001-02 where the QBO was in the -mid 20's late summer...and rebounded to positive territory by December.

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16 hours ago, *Flash* said:

It seems when the QBO is this negative going into August, it almost always stays negative into November (which can be a fair indicator in a winter weather forecast). Fingers crossed we don't have another 1994-95 or 2001-02 where the QBO was in the -mid 20's late summer...and rebounded to positive territory by December.

It is late on Sunday...something else about the QBO.  I think there is a point during the winter that we don't want to see it moving quickly towards neutral.  Last winter was money because it dropped during the fall and continued throughout winter.  I think a falling QBO is generally better.  It could be a problem during late winter if it moves in a positive direction.  That might be about the time it should switch off the top of my head.  Also, off the top of my head, when it reaches its lowest point and comes up, that could mean a flip to warm...so something to watch as we head into winter.  As Jeff said, we want the QBO on a TKO and down for the count.

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4 hours ago, *Flash* said:

It seems when the QBO is this negative going into August, it almost always stays negative into November (which can be a fair indicator in a winter weather forecast). Fingers crossed we don't have another 1994-95 or 2001-02 where the QBO was in the -mid 20's late summer...and rebounded to positive territory by December.

Good point about 94-95,the qbo was rather strongly negative in July with Nino starting to develop into ASO,seems it would fit the pattern tho than 01-02 when the ENSO was neutral,but who knows either might be right,3.4 has yet to get  shown into Nino land

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ECMWF monthly charts turned colder. Previous issue showed a lot of late fall severe. CFS looks like previous. Current Euro update wants to get winter started quickly in December. 

Sept/Oct charts look fairly benign both temps and precip. November shows more precip. Novie weather pattern is unsettled but not particularly cold yet. Euro punted warm/severe though.

Dec/Jan show a seasonably cold to BN look. December verbatim is more unsettled. January has less precip. Note it can still snow with BN precip. Feb verbatim really does look dry though. I would not trust any of this until the October issue, so we have one more dummy issue in Sept.

Finally, QBO concerns above are legit. Signal depends on slope/sustainability. Plus it does not work every year. I prefer to follow ENSO and the PDO.

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I wonder if the weak Nino will be the driving factor.  I agree that ENSO is a massive player as well as the AMO/PDO.  I wonder if the QBO has a bigger impact during Ninas or Nadas.  Just seems like Ninos are an ace up the sleeve.  So, I do think the weak Nino(should it actually occur) is money.  Somewhere in one of the subforms, there was a sunspot graph for like the last 150 years.  Low sunspot numbers (solar mins) do correlate very well to nice winters in this region of the world - maybe even a decent correlation.  Again, we do not want the QBO to suddenly flip during mid winter....  The money call w the QBO is when it flips and drops during late fall or early winter.   Other than that, I am not sure how dependable it is once in a consistent negative state.  So, IMHO a dropping QBO that goes negative is a very good indicator of blocking up top.  Also, a QBO(though still deeply negative) that begins to quickly move to neutral is bad news.  Right now we are strongly negative w the QBO as Jax shared.  This may be a situation where a weak ENSO is battling a rotting -QBO.  What I am hoping for is that the usual time cycle for the QBO is a tad slower...and indeed it stayed positive much, much longer than normal last time.  But I think the seasonal models are seeing the weak Nino and a recent trend towards high latitude blocking.  I will be surprised if things get going early, but not overly.  Just seems that early winters are very difficult to come buy in NE TN though we have had a few recent ones.  Snow (at lower elevations) of more than 2-3" before Christmas happens...just not as often since say the 1980s.  And I say again....the kiss of death is an early season snow at lower elevations prior to Thanksgiving.  If that happens, I am calling "torch" right then.  Now the real whammy(the good kind) would be if the NAO positive cycle is over.

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At -29.10(30mb), the QBO does indeed seem primed for a flip.  Just glancing at the data, recent negative phases average 12-16 months.  We are on month 14.   Once the numbers slide in the negative 25-30s, the clock is ticking.  Like I said the only glimmer of hope is that the last positive cycle was an anomaly as it lasted seemingly forever.  Maybe this negative cycle will mirror that?  But if forced to predict, I think the QBO flips during late fall or December.  Just a guess, but we are on borrowed time.  Additionally, when they flip they can move to neutral quite quickly.  

https://www.esrl.noaa.gov/psd/data/correlation/qbo.data

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I was reading some information last night about the winters of 100 to 200 years ago in the region. It's incredible. 10 inches of snow on May 20th on the Plateau with feet in the Smokies, and I believe 2 inches in Knoxville. Snow fell in Tennessee but didn't stick in June 1865. The high temperature on July 4th in 1816 was likely in the 40s in Knoxville. There were multiple 15+ inch snow events in the valley region but there were no official records. Only newspaper reports. 

Throughout the 1800s and into the Early 1900s the Tennessee river would freeze over in Knoxville and ice flows from the Clinch and other tributaries would flow into Knoxville. At one point the river froze so solidly that it was 12 inches thick in the middle and people were driving wagons across it. It snowed so regularly in December Knoxville had a sleigh festival on a yearly basis.

In more recent times there was the wild November 1952 snow storm that effected Corbin Ky to Scott County to the Tri-Cities down through Knoxville to Athens. I was reading an old newspaper report from then that said a man who lived in Powell worked in Kingston for TVA. He left Kingston with no snow on the ground and arrived in Knoxville to find 12 inches in West Knox county and 20 inches by the time he arrived in Powell.  It was an incredible cut-off from no snow to over a foot of snow. 

There was the crazy 1951 event from the Plateau west where that area was buried in snow and ice, but the Knoxville to Tri-Cities area only received .2 inches of ice and didn't get nearly as cold as Nashville.  Tri-Cities was 60 degrees on Jan 31st, Knoxville, barely west of Tri was 44, and west of Knoxville it was in the 20s and 30s with freezing rain, sleet and snow all day. The next day it was 62 at Tri, a midnight high of 45 in Knoxville and 22 in Nashville.  Areas from the Plateau west ended up with 3-5 inches of solid ice compacted on the ground and temperatures 20-30 degrees colder than the far eastern valley areas.

We had similar weather a few years ago here in the February blitz but not quite to the extreme of that event. I enjoy looking back through old news paper articles to see this stuff. 

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Another reason why I say that each year is its own analog is that so many factors can influence winter but ENSO rarely steers my wrong.  But once the QBO, PDO, AMO, solar min/max, climate cycle, etc are added in....each winter has its own set of chromosomes.  Yes, a few might look like each other...but ultimately there are no carbon copies.  

John, great post!  Always like those.  I used to have a Biology teacher (way back in HS) that said he had grandparents that remember hearing trees explode during cold winters.  No idea if that can actually happen, but I remember the old folks when I was a kid talking about how bad winters were in the early quarter of the last century.

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Looking at the QBO reveals extremely mixed results heading into winter. 1984-1985 was a negative summer that went neutral to positive in winter. As a matter of fact, it was -27.10 in August of 1984. A record low at the time, after being -25.39 in July of 1984, also a record low.  In 2005-06 that record was broken, but then it peaked down in November at -29 after having set a record the prior month at -28, it managed to stay in the -25 range for December. That was not a good winter for snow/cold lovers. It was actually one of, if not the warmest winters I recall.  Both 1984-85 and 2005-2006 were weak La Nina years. But absolutely opposite in the intensity of winter. 

In 1959-1960 it was positive the entire winter. In 1995-1996 it was very weakly negative. In 1977-1978 it flipped from negative to positive in summer and stayed positive in winter. 

So to me, it seems to have little effect on the intensity of the winter we experience. We can be extremely mild while it's deeply negative and we can be extremely cold and snowy while it's positive. Then the opposite seems to occur too with about the same frequency. So I'm not sure it's a particularly useful tool to try and make a winter forecast. 

November can be very key though. We virtually always have a cold/snowy winter if it's the temps average below normal in November. 

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2 hours ago, John1122 said:

Looking at the QBO reveals extremely mixed results heading into winter. 1984-1985 was a negative summer that went neutral to positive in winter. As a matter of fact, it was -27.10 in August of 1984. A record low at the time, after being -25.39 in July of 1984, also a record low.  In 2005-06 that record was broken, but then it peaked down in November at -29 after having set a record the prior month at -28, it managed to stay in the -25 range for December. That was not a good winter for snow/cold lovers. It was actually one of, if not the warmest winters I recall.  Both 1984-85 and 2005-2006 were weak La Nina years. But absolutely opposite in the intensity of winter. 

In 1959-1960 it was positive the entire winter. In 1995-1996 it was very weakly negative. In 1977-1978 it flipped from negative to positive in summer and stayed positive in winter. 

So to me, it seems to have little effect on the intensity of the winter we experience. We can be extremely mild while it's deeply negative and we can be extremely cold and snowy while it's positive. Then the opposite seems to occur too with about the same frequency. So I'm not sure it's a particularly useful tool to try and make a winter forecast. 

November can be very key though. We virtually always have a cold/snowy winter if it's the temps average below normal in November. 

The drop during the fall season (where it goes negative) is a pretty good signal for blocking IMO.  Last couple of winters it has been pretty good tool, but like most wx tools it does not work well without other metrics.  I do think there are some winters where it is not a good signal, and indeed this one might be iffy.  Whether it had anything to do w the strat split last spring is open for debate.   @Isotherm has used the QBO(in his seasonal forecasts) before which is where I learned about the tool.  I will tag him and see if he cares to comment.  The QBO rise during winter can be a good sign for a flip to warming temps.   To me the trajectory seems to signal/not signal blocking.  I don't really see it as determining intensity of the overall winter.  Blocking in the eastern valley, especially NE TN, can be a big player where we Atlantic storms do pump moisture over the mountains.  That said, I will always agree that ENSO is a major trump card.  I do think the optimum set-up for snow is slightly different in NE TN when compared to the northern Plateau as we just don't get the forcing that you all do - which is why Atlantic systems that throw moisture back over the Apps are prime for big snows here.  Middle and west TN have very different setups unless we all manage a slider.  As for the rising QBO, it does not necessarily mean that the winter is warm...just means that a quick flip to spring is possible (again, off the top of my head).  I "think" 84-85 actually had that flip.  Just saying that the when the QBO begins to have a strong positive trajectory, things can flip warm suddenly.  I will do some more digging.  Hopefully, Isotherm will stop in and add his two cents.  He has forgotten more than I will ever know.

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