Jump to content
  • Welcome to American Weather

    Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customize your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more! This message will be removed once you have signed in.

AMZ8990

Winter Speculation 2018/19

Recommended Posts

22 minutes ago, Carvers Gap said:

I highly doubt the track, once inland, is nailed down yet.  NE TN was on the left side of the cone two days ago.  Now, we are on the right.  I don't have a ton of confidence that this is going to go where it is currently modeled(once inland).  I do think it is going to meander - and that is not good for the communities in the SE US wherever that happens.  What we really need to hope for is that this storm picks up speed and does not stop.  I think the mountains of NC (southwest corner to northwest corner) need to really watch this.  Seems that one constant is that they are increasingly at risk of flooding rains of maybe an unusual scale.  It is still possible that Florence actually misses the southern Apps w a southern trend.  But again, w low steering currents this is going to have a mind of its own so to speak.  Interesting to follow but very concerned for coastal communities of the SE coast as this storm will slowly(and I mean slowly as modeled) move on shore after first making a SE jog(still not totally sure I buy that).  The Gulf Stream will fuel that storm in the northeast quadrant even if part of the storm is barely onshore.  Downsloping winds will be the story here.  That would likely mean that the eastern side of the eastern TN Valley would see less rain but decent downsloping winds.  Not sure what would happen when those winds hit the upslope of the Plateau, though I think I know what it should do which is rain.  Once the remnants of Florence move into Tennessee per the Euro, then NE TN gets rain.  Still, uncertainty is the key word.  Nothing set in stone, though like I said, the mountains of NC need to really watch this.   @Math/Met, would the 0z Euro create a tropical induced (sorry...don't know of a better term) mountain wave even in places like Camp Creek?  

Could the Bermuda high help any in giving this storm some push in the right direction.  Or are we past the point where the high could effect Florence now?

Share this post


Link to post
Share on other sites

Wish a single thread were made for Florence. Let's keep this thread for overall fall & winter pattern discussion if we could.

I know most are focused Florence right now & rightfully so. But holy moly on JMA Seasonal for DEC!! Average Oct, warm Nov. BUT DEC...robust -EPO, -NAO (blocking mostly around Davis Strait). Looks very similar to updated Euro:

The entire winter looks NUTS also. Look at 3 month first & you can change through individual OCT/NOV/DEC.

 

Then you can click on DEC-FEB mean on first page of link. Good stuff...if you like winter! Winter mean has robust -EPO, -NAO, -AO combo.

http://ds.data.jma.go.jp/tcc/tcc/products/model/map/4mE/map1/pztmap.php

  • Like 2

Share this post


Link to post
Share on other sites
47 minutes ago, stadiumwave said:

Wish a single thread were made for Florence. Let's keep this thread for overall fall & winter pattern discussion if we could.

I know most are focused Florence right now & rightfully so. But holy moly on JMA Seasonal for DEC!! Average Oct, warm Nov. BUT DEC...robust -EPO, -NAO (blocking mostly around Davis Strait). Looks very similar to updated Euro:

The entire winter looks NUTS also. Look at 3 month first & you can change through individual OCT/NOV/DEC.

 

Then you can click on DEC-FEB mean on first page of link. Good stuff...if you like winter! Winter mean has robust -EPO, -NAO, -AO combo.

http://ds.data.jma.go.jp/tcc/tcc/products/model/map/4mE/map1/pztmap.php

Think i agree,either a thread should be made or move this to summer

Share this post


Link to post
Share on other sites

We are in fall and it's part of the weather that's happening in the future. So I don't have any issue personally with it being here. But maybe we need a short term thread and we can leave this the long term thread for beyond 5 days discussion? 

  • Like 1

Share this post


Link to post
Share on other sites
27 minutes ago, John1122 said:

We are in fall and it's part of the weather that's happening in the future. So I don't have any issue personally with it being here. But maybe we need a short term thread and we can leave this the long term thread for beyond 5 days discussion? 

Ditto.  No doubt...I think we only have like a page and a half of posts on Florence anyway.  So, it is not like the hurricane talk is taking over.  And I agree, Florence is part of the pattern discussion.  I don't think many would have made a storm thread(until today) as the actual system was not really dialed-in until yesterday.  We barely have enough posters to keep this thread going...much less two threads.  When we go back and look at seasonal threads, we need what occurred during that season.  This is not a winter thread.  Maybe we need to split the Winter Speculation and Fall topics into two threads?....Not sure that we need a separate thread for a wind and rainmaker.  Honestly, those folks in the SE have it so bad...seemed a bit odd to have a thread just for the remnants.  

Share this post


Link to post
Share on other sites

Yeah, I think the problem is the fall pattern thread and the winter speculation thread need to be two separate threads.  That said, with so few people posting I can see why just one thread was needed.  But I think the problem is that the pattern thread which rightly includes Florence is washing out the winter discussion.   I don't think a Florence thread will fix that.  What we need to do IMHO is to leave this as the winter speculation thread(since that is what it began as) and then make a fall pattern thread.  That would solve the problem.   Otherwise, we are going to have to keep making event specific threads for events that may not be substantial for most in this forum, especially during this time of the year when we have fewer posters.  Really, all that it would take is to simply rename this as the original winter speculation thread and then make a new fall pattern thread.  

  • Like 2

Share this post


Link to post
Share on other sites
1 hour ago, stadiumwave said:

Wish a single thread were made for Florence. Let's keep this thread for overall fall & winter pattern discussion if we could.

I know most are focused Florence right now & rightfully so. But holy moly on JMA Seasonal for DEC!! Average Oct, warm Nov. BUT DEC...robust -EPO, -NAO (blocking mostly around Davis Strait). Looks very similar to updated Euro:

The entire winter looks NUTS also. Look at 3 month first & you can change through individual OCT/NOV/DEC.

 

Then you can click on DEC-FEB mean on first page of link. Good stuff...if you like winter! Winter mean has robust -EPO, -NAO, -AO combo.

http://ds.data.jma.go.jp/tcc/tcc/products/model/map/4mE/map1/pztmap.php

November warmth is never a good sign for winter weather. If the mean temp in Knoxville for November is above 48 degrees, the winters are almost always lacking in snow/cold in this part of the valley at least. Not checked on the western valley but I imagine their results are similar. The new normal for Knox in the 1981-2010 climate cycle is 49 in November, thus a large number of very poor winter performances during that time. But when November has managed to come in below average, the winters have tended to be cold/snowy at some point. In 2014 the November mean temp averaged 41.6 at Knoxville (I recorded this number in the 2014 thread, and I went back and looked at the NWS official record and it's been changed to 43.2, no idea how it got almost 2 degrees warmer 4 years later.) and I talked about that in the winter pattern discussion. 2014-15 ended up being quite excellent for snow/cold. So pull for that to be wrong about November if you want the white stuff to pile up!

  • Like 2

Share this post


Link to post
Share on other sites
2 minutes ago, John1122 said:

November warmth is never a good sign for winter weather. If the mean temp in Knoxville for November is above 48 degrees, the winters are almost always lacking in snow/cold in this part of the valley at least. Not checked on the western valley but I imagine their results are similar. The new normal for Knox in the 1981-2010 climate cycle is 49 in November, thus a large number of very poor winter performances during that time. But when November has managed to come in below average, the winters have tended to be cold/snowy at some point. In 2014 the November mean temp averaged 41.6 at Knoxville (I recorded this number in the 2014 thread, and I went back and looked at the NWS official record and it's been changed to 43.2, no idea how it got almost 2 degrees warmer 4 years later.) and I talked about that in the winter pattern discussion. 2014-15 ended up being quite excellent for snow/cold. So pull for that to be wrong about November if you want the white stuff to pile up!

Ugh.  Good catch.  Our numbers at TRI are not even reliable anymore regarding snowfall(so much missing data on well-known storms), even during ongoing events but especially for historical numbers.  Even though we are in different regions and elevations, I actually rely on your numbers more because they don't change.  I haven't even looked at our temp numbers....prob would just make me mad.  What is nice about this forum is that we can record information that will not get altered for whatever reason.

Share this post


Link to post
Share on other sites
1 hour ago, AMZ8990 said:

Done!

AMZ, would you be willing to change the Florence thread to Fall Pattern and flip this one back to winter speculation?  edit...OR just make this the winter spec thread, keep the Florence thread, and create a fall pattern thread.

Share this post


Link to post
Share on other sites
3 minutes ago, Carvers Gap said:

Ugh.  Good catch.  Our numbers at TRI are not even reliable anymore regarding snowfall(so much missing data on well-known storms), even during ongoing events but especially for historical numbers.  Even though we are in different regions and elevations, I actually rely on your numbers more because they don't change.  I haven't even looked at our temp numbers....prob would just make me mad.  What is nice about this forum is that we can record information that will not get altered for whatever reason.

The NWS numbers are completely unreliable, especially snowfall numbers. This was the first I'd noticed that much temperature fudging. There's a station near here in Newcomb. It recorded snowfall, rainfall and temp data for most of the the last 60 years or so until I believe 2012.  It held the state record for snowfall in 24 hours for the November 1952 storm with 22 inches, that stood until the Blizzard of 1993 and LeConte started having official recordings.  According to NWS records that station averages 2.5 inches of snowfall per year from 1951-2012. The stations in Jamestown and Tazewell are slightly further south and close in elevation, Tazewell averages 16.4 inches and Jamestown 18.2 inches over the same time period. They also claim Oneida, also in the same latitude/elevation range, only averaged 7.5 for that period. So they "lose" data and apparently just slap a 0 on the snowfall total for the day and plow ahead and average it out.

  • Thanks 1

Share this post


Link to post
Share on other sites
1 hour ago, Carvers Gap said:

AMZ, would you be willing to change the Florence thread to Fall Pattern and flip this one back to winter speculation?  edit...OR just make this the winter spec thread, keep the Florence thread, and create a fall pattern thread.

I can handle that.  I’ll have it done soon.

Share this post


Link to post
Share on other sites
2 hours ago, AMZ8990 said:

I can handle that.  I’ll have it done soon.

Thanks.  I pulled my Florence posts...that way this will be only a winter speculation thread.  Otherwise in five years, this will not make any sense to have hurricane posts in a winter spec thread. 

Share this post


Link to post
Share on other sites
4 hours ago, John1122 said:

November warmth is never a good sign for winter weather. If the mean temp in Knoxville for November is above 48 degrees, the winters are almost always lacking in snow/cold in this part of the valley at least. Not checked on the western valley but I imagine their results are similar. The new normal for Knox in the 1981-2010 climate cycle is 49 in November, thus a large number of very poor winter performances during that time. But when November has managed to come in below average, the winters have tended to be cold/snowy at some point. In 2014 the November mean temp averaged 41.6 at Knoxville (I recorded this number in the 2014 thread, and I went back and looked at the NWS official record and it's been changed to 43.2, no idea how it got almost 2 degrees warmer 4 years later.) and I talked about that in the winter pattern discussion. 2014-15 ended up being quite excellent for snow/cold. So pull for that to be wrong about November if you want the white stuff to pile up!

 

2014 is a bad example. 2014 was 100% because of recurring typhoon Nuri bottoming out in the Bering Sea. Caused a monster ridge & trough. 

But NOV 1977, 1986, 2009 were all torch NOV.  And all of those were modoki winters & 2 of them cold & snowy ones. 

Can't use the word "never" when it comes to weather. :)

  • Like 1

Share this post


Link to post
Share on other sites
6 hours ago, stadiumwave said:

 

2014 is a bad example. 2014 was 100% because of recurring typhoon Nuri bottoming out in the Bering Sea. Caused a monster ridge & trough. 

But NOV 1977, 1986, 2009 were all torch NOV.  And all of those were modoki winters & 2 of them cold & snowy ones. 

Can't use the word "never" when it comes to weather. :)

Those years you listed stadium were as you said. 77 Nov. Was mild till after 20th then winter set in with a vengeance , long, cold and snowy. 86 was a mild Nov. Then slightly colder than avg. Winter with very snowy spine of apps eastward(note: 2-3 feet of snow April 87 here ). 09-10 cold / snowy Dec thru Feb. . A nws statistic several years ago had a correlation of 60% odds of cold winter when Nov is cold. So, some greater prob. If it's cold.

Share this post


Link to post
Share on other sites
19 hours ago, stadiumwave said:

 

2014 is a bad example. 2014 was 100% because of recurring typhoon Nuri bottoming out in the Bering Sea. Caused a monster ridge & trough. 

But NOV 1977, 1986, 2009 were all torch NOV.  And all of those were modoki winters & 2 of them cold & snowy ones. 

Can't use the word "never" when it comes to weather. :)

There are exceptions, as there always are in any kind of analog. But the majority of warmer than 48 degree Novembers in Knoxville resulted in less than stellar to down right terrible winters.

These are the two 500mb vs normal for DJF from the top 20 warmest Novembers since 1948 vs the top 20 coldest since 1948. 

 

heightsvsnormalwarmnov.png

heightsvsnormalcoldnov.png

  • Like 1
  • Thanks 1

Share this post


Link to post
Share on other sites

The anomaly in the PAC NW during the warm November is pretty significant when averaged over a 20 different years. It's hard to move the bar that much from average over a long period of years. But those years appear to feature a rampaging -PNA which would lead to there being significant western troughs in those winters. There are a few great winters in there and there are a few clinkers in the cold Novembers but by far we want the cold November 500mb pattern vs the warm one. 

  • Like 2

Share this post


Link to post
Share on other sites
On 9/13/2018 at 12:31 PM, John1122 said:

There are exceptions, as there always are in any kind of analog. But the majority of warmer than 48 degree Novembers in Knoxville resulted in less than stellar to down right terrible winters.

These are the two 500mb vs normal for DJF from the top 20 warmest Novembers since 1948 vs the top 20 coldest since 1948. 

 

heightsvsnormalwarmnov.png

heightsvsnormalcoldnov.png

 

 

When averaging that many years it only takes a few extremes to really mess with blend. I recommend going through all the winters you listed in the warm NOV. There were some really good winters. There were also a few extremely warm winters that skew the mean.

 

Point is if we have a warm NOV it is not cancel winter. 

  • Like 2

Share this post


Link to post
Share on other sites
3 hours ago, stadiumwave said:

 

 

When averaging that many years it only takes a few extremes to really mess with blend. I recommend going through all the winters you listed in the warm NOV. There were some really good winters. There were also a few extremely warm winters that skew the mean.

 

Point is if we have a warm NOV it is not cancel winter. 

Actually, the 40 total winters in the past 70 years is a pretty big statistical pool and and the 500mb pattern in each set is glaring and it isn't swayed by one or two winters in the set. NOAA sets new climatological norms based on 30 years. If we have a warm November we might not lose, but we're down 10 going into the 4th quarter and the other team is playing good defense. That big -PNA that shows up after warm Novembers is the worst possible winter pattern here, we can make almost every other pattern work if we can get cooperation in that region, but if the PNA is deeply negative, we're going to have warm SW flow and cutters as a rule during those winters. It shows up in the final snow tallies as well, 7 of the 10 snowiest winters in the region came following years with BN Novembers. Including the legendary 1959-60 winter, 1984-85 and 1995-1996.. On the flip side, 7 of Knoxville's 10 least snowy winters came after above average Novembers. 

  • Like 2

Share this post


Link to post
Share on other sites
19 hours ago, John1122 said:

Actually, the 40 total winters in the past 70 years is a pretty big statistical pool and and the 500mb pattern in each set is glaring and it isn't swayed by one or two winters in the set. NOAA sets new climatological norms based on 30 years. If we have a warm November we might not lose, but we're down 10 going into the 4th quarter and the other team is playing good defense. That big -PNA that shows up after warm Novembers is the worst possible winter pattern here, we can make almost every other pattern work if we can get cooperation in that region, but if the PNA is deeply negative, we're going to have warm SW flow and cutters as a rule during those winters. It shows up in the final snow tallies as well, 7 of the 10 snowiest winters in the region came following years with BN Novembers. Including the legendary 1959-60 winter, 1984-85 and 1995-1996.. On the flip side, 7 of Knoxville's 10 least snowy winters came after above average Novembers. 

 

So...again, you're not getting the point. I'm NOT arguing about the fact that statistically odds decrease for a cold winter in tn valley after a warm NOV. 

I'm arguing that your word "NEVER" (used in your original post in reaction to JMA) is wrong & you just unknowingly admitted that in your post above. Chances of a cold winter after a warm NOV may decrease significantly but they are NOT eliminated. A -PNA NOV is not a guarantee of a -PNA DJF. That's all I'm arguing. Hence my pointing out the cold winter years in your 40 years...which destroys the word "NEVER". 

Not sure I can break it down anymore than that. ;)

 

Share this post


Link to post
Share on other sites
5 hours ago, stadiumwave said:

 

So...again, you're not getting the point. I'm NOT arguing about the fact that statistically odds decrease for a cold winter in tn valley after a warm NOV. 

I'm arguing that your word "NEVER" (used in your original post in reaction to JMA) is wrong & you just unknowingly admitted that in your post above. Chances of a cold winter after a warm NOV may decrease significantly but they are NOT eliminated. A -PNA NOV is not a guarantee of a -PNA DJF. That's all I'm arguing. Hence my pointing out the cold winter years in your 40 years...which destroys the word "NEVER". 

Not sure I can break it down anymore than that. ;)

 

You are missing the point, I used the word never in the correct sense but for some reason you don't comprehend quite what I said. I said November warmth is never a good sign for winter weather.   I'm really not sure what point you are possibly trying to make disputing that. Are you saying that a warm November is a good sign for DJF? Can you show me some actual scientific evidence that if you like winter weather in the area that it's good to have a warm November? I'd actually be encouraged if it exists.

 I pretty clearly broke down the reasons why November warmth is never a good sign for winter weather here. The 500mb pattern is on average, hostile to chances of winter weather in the DJF timeframe following them. This pattern pretty clearly plays out in the 7-3 split both ways in regards to the snowiest winters vs the most snow free winters in the area.

It could be 5 degrees above normal here this November and then snow 2 feet this winter valley wide, but my post would still be true because that scenario happens way less often after a warm November than it does after a cold November.  Thus a warm November is never a good sign for winter weather. 

 

  • Like 2

Share this post


Link to post
Share on other sites

I definitely like where this evening's Euro Weeklies are heading very late in the run.  Take that w a huge tablespoon of salt as it is shoulder season and waaaay out there.  However, that run (and to some extent the past couple of runs) wants to drive the season's first cold air mass south during mid-late October followed by seasonal temps...but w pretty decent blocking in the form of a -EPO and -NAO building.

  • Like 4

Share this post


Link to post
Share on other sites
14 hours ago, Carvers Gap said:

I definitely like where this evening's Euro Weeklies are heading very late in the run.  Take that w a huge tablespoon of salt as it is shoulder season and waaaay out there.  However, that run (and to some extent the past couple of runs) wants to drive the season's first cold air mass south during mid-late October followed by seasonal temps...but w pretty decent blocking in the form of a -EPO and -NAO building.

I concur. If you like early season skiing in the Rockies and/or Aleutians storms pumping up that +PNA, cheers. For here, I'm more optimistic than I was this time last week. All that early season snow and cold up in Canada has to move at some point. Model blends hint at the first fall front/trough rotating through before month's end. Tomato, Tamato if it's September 28 or October 4...as long as we can kiss the 90's/upper 80's goodbye. Local cool downs rarely feel gradual...and next month looks like it may play the part. Speaking of Euro Ensembles, let's hope Florence doesn't reloop back into the Carolinas next week. I imagine % are low, but still...unsettling if you're a weather weenie in the SE forum.

  • Like 2

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

×