Jump to content
  • Member Statistics

    17,605
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

2016-2017 Great Tennessee Valley Winter Discussion


John1122

Recommended Posts

4 minutes ago, Carvers Gap said:

Euro weeklies update...@500

w1:  nationwide trough

w2:  positive tilted trough in sw Canada / ridge from the southwest to northeast

w3:  trough retrogrades in GOA / most of NA w AN heights / AK cold

w4:  big changes...AN heights over the Hudson Bay trough east/ridge west...

w5:  huge PNA ridge into AK...trough east/ridge west...BN heights in east

w6: continued massive PNA ridge...trough east/ridge west...BN heights in east

part of week 7:. Same patter as wk5 w deepening eastern trough...big cold signal

Overall..IMO a good run at 500mb.  2m temps often don't correlate on the weeklies, but will try to add those to this post later.  In a nutshell, very hostile winter pattern coming up after this week.  Good thing is it looks to last only 10-14 days and is more of a transition to an eastern trough/western ridge pattern.  The western trough retrogrades into the GOA and that is the beginning of the end of this current pattern.  Again, a great rule is a pattern generally runs 30-45 days, sometimes 60 such as this.after week 3 no hint of a SER.  Wk3 there is barely any western trough as we go zonal that week.

Probably the best run of weeklies we have seen this season.

Link to comment
Share on other sites

  • Replies 1.6k
  • Created
  • Last Reply
3 minutes ago, Met1985 said:

Probably the best run of weeklies we have seen this season.

Agree.  Edited a couple of typos from my earlier post and added a question.  Prob better than most last season.  Either way...this actually looks like a pattern that could evolve from the current pattern based on LR models.  Three good runs of the weeklies in a row, colder at 500 w each run.  

Link to comment
Share on other sites

17 minutes ago, Carvers Gap said:

Agree.  Edited a couple of typos from my earlier post and added a question.  Prob better than most last season.  Either way...this actually looks like a pattern that could evolve from the current pattern based on LR models.  Three good runs of the weeklies in a row, colder at 500 w each run.  

Not bad at all,lets see what happpens to the PV upcoming and what kind of blocking we can get and look into Asia for storms.

Link to comment
Share on other sites

If I lived up north, I might be less than enthused about the weeklies in that we lose two weeks(give or take a few days) of prime winter months.  But in reality we get about a four week or so stretch of chances.  The weeklies have that modeled.  Sure, it could be wrong.  Might hit a good pattern with no cold.  But we are going to have to get through a stretch of temps that most likely will tip this winter warm (on the averages) no matter what comes after...but who knows, easily could be some surprises tucked into those warm weeks.

Link to comment
Share on other sites

15 minutes ago, Carvers Gap said:

Interestingly...looked at the 46 day weeklies mean and it is normal for temps statewide.  Just thought I would add that.  Big swings.

Looking at the control,its more Nina looking with the highest precip into the Ozarks into the OV,think very well possible this winter with cold air into  might be trapped into Central Canada by the looks this winter might not last past mid Feb..JMO

Link to comment
Share on other sites

50 minutes ago, jaxjagman said:

Looking at the control,its more Nina looking with the highest precip into the Ozarks into the OV,think very well possible this winter with cold air into  might be trapped into Central Canada by the looks this winter might not last past mid Feb..JMO

I rarely use the control on the weeklies, because it is a crapshoot since it is one run.  I was just looking at the the model output on the mean.  The mean precip shield is over the SE and TN Valley.  We actually do OK during some weak Nina patterns...just not during summer IMO.   Did some reading from the Australia Governemnt wx services.  Off the top of my head they seem to like neutral after this winter w maybe one month mixed in as Nina.  Definitely this winter has behaved as a Nina minus a couple of things....some big snows here and in the Deep South.  Weak Ninas are usually money here and at some point it would seem likely the eastern half of the country should see some big storms based on climo.  There is definitely some evidence that Ninas can end winter early.  But just speaking of the weeklies only...winter is in full force mid-Feb.  

Link to comment
Share on other sites

We could always go to the 1989 analog and winter just ends early.  I like the 95-96 analog but scaled way down.  There are some similarities to this winter and some not.  Even the date for this upcoming whif (?) is in a similar time frame to a big event then.  My point is that winter featured the worst cold in late January and had wild swings.  Good read and some decent nuggets.  FTR...in no way am I saying we go anywhere near this extreme.  

http://www.cpc.ncep.noaa.gov/products/assessments/assess_96/winter.html

Link to comment
Share on other sites

19 hours ago, Carvers Gap said:

Euro weeklies update...@500

w1:  nationwide trough

w2:  positive tilted trough in sw Canada / ridge from the southwest to northeast

w3:  trough retrogrades in GOA / most of NA w AN heights / AK cold

w4:  big changes...AN heights over the Hudson Bay trough east/ridge west...

w5:  huge PNA ridge into AK...trough east/ridge west...BN heights in east

w6: continued massive PNA ridge...trough east/ridge west...BN heights in east

part of week 7:. Same pattern as wk5 w deepening eastern trough...big cold signal

Overall..IMO a good run at 500mb.  2m temps often don't correlate on the weeklies, but will try to add those to this post later.  In a nutshell, very hostile winter pattern coming up after this week.  Good thing is it looks to last only 10-14 days and is more of a transition to an eastern trough/western ridge pattern.  The western trough retrogrades into the GOA and that is the beginning of the end of this current pattern.  Again, a great rule is a pattern generally runs 30-45 days, sometimes 60 such as this. Aftter week 3 no hint of a SER.  Wk3 there is barely any western trough as we go zonal that week.  Nice run of the weeklies if you can live with weeks 2-3 being warm.  Last full week of Jan begins a very good stretch of winter after a two week ridge.  Definite pattern change depicted...and hopefully to the good.  Only question is how much of NA gets scoured of cold air during the warm-up?

Thanks for the detailed summary!! 

Link to comment
Share on other sites

What is encouraging about the MJO graphics above is that the weeklies and LR models do support the warm-up.  That may sound crazy, but it means that they are correlating pretty well to the MJO phases.  If they correlate when it is warm, they should when it is cold as well.  PSU has a great post on the MA forum about how the AN heights that are being shown over the Hudson Bay in the LR by the GEFS will help build heights in the West which could eventually evolve to a trough in the East.  IMO, that also fits the timeframe of the MJO forecast above.  So, it does appear there is a way out of this and fits with the idea that the current pattern has just about run its course.  We have been in some form of "trough west ---> cold bleeds East" pattern for since November.  Let's just hope we have a cold source when the eastern trough arrives.  Just click on the box for PSU's comments...

 

Link to comment
Share on other sites

8 minutes ago, Olhausen said:

Man I really want no part of this if it were to verify.


b3ca0adcfe3112dd05b0f640cd52326c.png

c47b8c38c5a816fb8851174afa62f69e.png


Sent from my iPad using Tapatalk

Send it on to me. I feel like winter is slipping away. Until this system came along, I didn't see our winter weather being much different than in west central California (and how boring they are). Don't get me wrong, I appreciated the 2 inches of snow, but I'd really like to see 4" or more in one clip. And if we got some ice, and as long as does no real damage, it's okay with me. I'd just be not fool enough to try to drive on it.

Link to comment
Share on other sites

With the snow having run its course and warming temperatures later, this weekend will seem like a distant memory. Due to this storm, annual totals are back at around average or somewhat above average for northern areas of the Tennessee Valley. The question we must attempt to answer now is how long the upcoming relatively warm pattern will be in place. Although the conversation over this has already started I felt the need to set a certain question to be answered by a prediction or at least pondered upon over the next few weeks. Here are some of the CFS weekly anomalies for 2m temperature and precipitation. In the Following posts

Link to comment
Share on other sites

57 minutes ago, Olhausen said:

Man I really want no part of this if it were to verify.





I should add that this would start around 6AM next Saturday. The time stamp on the picture is not the correct start time.

Sent from my iPad using Tapatalk

Last I looked this was similar to the under cutting arctic front from a couple weeks ago. 

Link to comment
Share on other sites

24 minutes ago, John1122 said:

Last I looked this was similar to the under cutting arctic front from a couple weeks ago. 

I am torn in thinking this retroging trough into AK is a stable, new pattern...or if is a transition to an eastern trough.  The AN heights build into Canada scouring the cold there.  Takes us right back to November when the pattern changed and it took three weeks to build cold.  But what is interesting is seeing some BN or normal heights at 500mb try to sneak under those very high heights in the East.  Several strong pieces of energy cutting at the base of the eastern ridge.  When a cold front manages to crash the ridge...would be interesting to see if timing would allow for one of those potent systems fo get picked-up.  Enough marginal cold around since it is Jan.  Bit of a long shot in what is looking more and more like a very warm pattern that has more holding power than I thought.  I hope the MJO can work its magic as it is forecast to roll through phases 8,2, and 1 later this month. So my questions as we go forward....Does the warm-up really hold?  (modeled long term heat or cold has never held in the East) When the MJO hits prime territory, will we have any cold left in Canada which by then will have been well above normal for 2-3 weeks?

Side note...95-96 (on a very scaled down level) comes to mind as does '89.  One good.  One not good.  Also, the blocking signal from a couple of weeks ago bore some fruit.  Something to watch for if it happens again...even if transient.

Link to comment
Share on other sites

Send it on to me. I feel like winter is slipping away. Until this system came along, I didn't see our winter weather being much different than in west central California (and how boring they are). Don't get me wrong, I appreciated the 2 inches of snow, but I'd really like to see 4" or more in one clip. And if we got some ice, and as long as does no real damage, it's okay with me. I'd just be not fool enough to try to drive on it.

This would do massive damage if it were to verify as is. Some areas would see over an inch of freezing rain and power would be gone for over a week in some places.

Sent from my iPad using Tapatalk

Link to comment
Share on other sites

6 minutes ago, Olhausen said:

This would do massive damage if it were to verify as is. Some areas would see over an inch of freezing rain and power would be gone for over a week in some places.

Sent from my iPad using Tapatalk

18z GEFS members are northwest of the op which is good news I agree.  Still, plenty of energy sliding under the well AN heights to our north.  Something to watch,

Link to comment
Share on other sites

4 minutes ago, Carvers Gap said:

18z GEFS members are northwest of the op which is good news I agree.  Still, plenty of energy sliding under the well AN heights to our north.  Something to watch,

Yes, hopefully will change by the time we get to that period but did not like the looks of that run at all besides I thought it was suppose to be warmer next week!

Link to comment
Share on other sites

7 minutes ago, weathertree4u said:

Yes, hopefully will change by the time we get to that period but did not like the looks of that run at all besides I thought it was suppose to be warmer next week!

I know.  Warm up is going to happen...AN heights will be centered eventually in eastern Canada.  Models have hinted in recent days that some storms are going to cut under that ridge.  For the time being, the cold in western Canada can still cause mischief as cold fronts will still press east. It is a great example of how warm patterns can produce sometimes.  Not saying it is going to...but it is January.  Climo is on our side.  Also, weak Nina climo favors this area for snow and the mid-South.   I would like to see one good run at winter where we can track multiple systems this year.

Link to comment
Share on other sites

6 minutes ago, Carvers Gap said:

I know.  Warm up is going to happen...AN heights will be centered eventually in eastern Canada.  Models have hinted in recent days that some storms are going to cut under that ridge.  For the time being, the cold in western Canada can still cause mischief as cold fronts will still press east. It is a great example of how warm patterns can produce sometimes.  Not saying it is going to...but it is January.  Climo is on our side.  Also, weak Nina climo favors this area for snow and the mid-South.   I would like to see one good run at winter where we can track multiple systems this year.

I agree, it would be great to have more winter storms this year to track for our area.  Time will tell.

Link to comment
Share on other sites

This would do massive damage if it were to verify as is. Some areas would see over an inch of freezing rain and power would be gone for over a week in some places.

Sent from my iPad using Tapatalk



Holy crap! I didn't see a scale, so had no idea it was that bad. No, I'd pass on that too.

Sent from my SAMSUNG-SM-G891A using Tapatalk

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...