2016-2017 Great Tennessee Valley Winter Discussion

[Reb]

Euro coming in much different than 12z. Storm is there and temps are marginal to warm across the eastern 2/3 of the state through 138

[jaxjagman]

1 hour ago, John1122 said:

I hope so, I know the GFS will feature surface solutions that sometimes don't match up with what upper patterns should produce. 

It doesnt mean snow but it should more or less show a pattern upcoming,notice how the heights build into China,this should be a ridge in the SW

[jaxjagman]

16 minutes ago, Reb said:

Euro coming in much different than 12z. Storm is there and temps are marginal to warm across the eastern 2/3 of the state through 138

yep,still think this will get better,fingers crossed anyways..lol

ECMWF Deterministic FORECAST FOR: BNA    LAT=  36.12 LON=  -86.68 ELE=   591

                                            00Z JAN01
                 2 M     850    1000    FZING    SFC     SFC    6 HR    SNCVR
                 TMP     TMP     850     HGT     WIND    PCP     QPF     LIQ 
                 (C)     (C)     THK    (FT)    (KTS)   TYPES   (IN)    (IN) 
SUN 00Z 01-JAN   5.3     4.7     132    7629    15004           0.00            
SUN 06Z 01-JAN   7.4     5.8     134   10109    17005           0.09            
SUN 12Z 01-JAN   8.0     7.3     134   10646    08003           0.07            
SUN 18Z 01-JAN  10.5     8.9     135   10513    10004           0.06            
MON 00Z 02-JAN  11.8     9.4     136   10245    15005           0.04            
MON 06Z 02-JAN  12.1    11.1     136   10566    16005           0.00            
MON 12Z 02-JAN  11.6    10.6     136   10311    11003           0.00            
MON 18Z 02-JAN  15.2    11.8     137   10352    15008           0.03            
TUE 00Z 03-JAN  15.5    12.4     138   10377    15009           0.05            
TUE 06Z 03-JAN  15.7    11.5     137   10594    15007           0.43            
TUE 12Z 03-JAN  14.6     9.5     137   12838    25007           0.11            
TUE 18Z 03-JAN  15.0     7.7     136   10888    28006           0.02            
WED 00Z 04-JAN  13.1     6.5     135    8868    30006           0.02            
WED 06Z 04-JAN  10.3     3.4     134    7318    32006           0.01            
WED 12Z 04-JAN   6.9     1.6     132    5293    34007           0.01            
WED 18Z 04-JAN   5.7    -0.5     131    3728    33007           0.00            
THU 00Z 05-JAN   2.3    -2.1     130    1173    34005           0.00            
THU 06Z 05-JAN  -1.1    -2.0     129       0    01006           0.00            
THU 12Z 05-JAN  -1.6    -3.2     129       0    05004           0.00            
THU 18Z 05-JAN   5.4    -3.0     130    1453    30000           0.00            
FRI 00Z 06-JAN   3.2    -2.0     130    2001    02005           0.01            
FRI 06Z 06-JAN   0.3     1.1     130    4564    36005           0.12            
FRI 12Z 06-JAN  -2.2    -2.9     128     816    35008           0.05            
FRI 18Z 06-JAN  -3.5    -6.2     127       0    34009           0.02            
SAT 00Z 07-JAN  -4.1    -9.6     126       0    35008           0.00            
SAT 06Z 07-JAN  -6.8   -12.7     125       0    35009           0.01            
SAT 12Z 07-JAN  -9.8   -13.9     124       0    34008           0.00            
SAT 18Z 07-JAN  -4.4   -11.1     125       0    34005           0.00            
SUN 00Z 08-JAN  -5.8    -7.1     126       0    30004           0.00            
SUN 06Z 08-JAN  -7.4   -11.1     126       0    28004           0.00            
SUN 12Z 08-JAN  -7.4                            31006           0.00            
SUN 18Z 08-JAN                                                      

[jaxjagman]

 Still believe this will get better,But we will warm up for a brief time,believe this should be further into the Valley coming up the 2nd image,looks like a good warm up either way

 

[John1122]

06z is a very warm, moist and amped after 00z was dry as a desert in the same timeframe as the 06 soaker. 

 Every single model run is night and day different right now. None can hold any solution for 24 hours.  We're going to have to ride this one out until it's onshore to get an idea imo.  

[John1122]

00z vs 06z.

[weathertree4u]

4 hours ago, jaxjagman said:

 Still believe this will get better,But we will warm up for a brief time,believe this should be further into the Valley coming up the 2nd image,looks like a good warm up either way

 

I am so confused and I follow the weather more than most people. Why exactly is it now suppose to warm? Honestly, this looks to me like the December pattern repeating. Cold chasing the moisture, cold for a couple of days, then warm and rain, then cold chasing the moisture, then cold for a couple of days, then more rain. Are you saying that you see something that makes you believe that the cold will hit and hold? If so, what is it because evidently all the other people that keep saying it are not seeing the right thing lol!

[Carvers Gap]

3 hours ago, weathertree4u said:

I am so confused and I follow the weather more than most people. Why exactly is it now suppose to warm? Honestly, this looks to me like the December pattern repeating. Cold chasing the moisture, cold for a couple of days, then warm and rain, then cold chasing the moisture, then cold for a couple of days, then more rain. Are you saying that you see something that makes you believe that the cold will hit and hold? If so, what is it because evidently all the other people that keep saying it are not seeing the right thing lol!

The current western trough will roll east late this week.  As another trough slides in to takes its place, it is split by a ridge.  One lobe rolls eastward and another piece stays in the West.  (It is odd to see a trough split by a ridge.) The pattern then continues w the trough in the West.  The ridge that splits the trough locks in the East and connects with a ridge in the North Atlantic.   There are many variations of this in the modeling, but it does fit with the MJO(euro) heading jnto phase 6 which is warm in the eastern half of the country. It has been on the models for several days.  That has made this window around the sixth important as it appears just a few days.  IMO, this is the beginning of the end for this pattern.  By mid-Jan, that makes about sixty days.  Tough for patterns to hold a shelf-life much longer than that.  Plus, one would guess that the MJO would roll through phase 7,8, and 1.  There is no guarantee the new pattern is any better, but the weeklies have hinted for two straight runs that a trough will take hold in the East later in the month.  The weeklies have had a disconnect between their 500mb pattern and the 2m temps.  500mb looks great and 2m is so-so.  The weeklies do habe the warm-up in ten days, but its duration is 5-10 days.  Mid-month roughly is the time frame for a pattern switch.  Until then, pattern is pretty hostile(other than the window we have been monitoring) towards winter weather. And again, no guarantee the new pattern is any better.

[Carvers Gap]

On Tropical Tidbits, you can view the new Cansips which is released at the beginning of each month.  It is not a pretty picture.  Very oddly, it looks like the operationals post d10.  I have a difficult time believing coincidences like that.  Either way, they do support the "winter will be front loaded with cold" camp.  In a minute I will post December's departures along w the Cansips so you can judge for yourself its verification.

[Carvers Gap]

Here is the Cansips for December followed by the temps through Dec 30 by Climates Signals.  IMO, that is not a great correlation, but it is not terrible either. 

 

 

[Carvers Gap]

4 hours ago, weathertree4u said:

I am so confused and I follow the weather more than most people. Why exactly is it now suppose to warm? Honestly, this looks to me like the December pattern repeating. Cold chasing the moisture, cold for a couple of days, then warm and rain, then cold chasing the moisture, then cold for a couple of days, then more rain. Are you saying that you see something that makes you believe that the cold will hit and hold? If so, what is it because evidently all the other people that keep saying it are not seeing the right thing lol!

Weathertree, a few posters outside of our own that I read are ustedtobe, PSU, and bobchill in the MA.  I also read posts by Jon, wow, lookout, and met1985 in the SE forum.  IDK, you may already read their posts, but it is good info for newcomers.  The MA has a great discussion right now about how the ridge post d10 is not static.  

[Matthew70]

30 minutes ago, Carvers Gap said:

Here is the Cansips for December followed by the temps through Dec 30 by Climates Signals.  IMO, that is not a great correlation, but it is not terrible either. 

 

 

Since it appears Jan. & Feb. are going to be warmer.  Do you believe it is going to be a very active early severe wx season?  Sorry if this question is in the wrong thread.  Thanks.

[Carvers Gap]

1 hour ago, Matthew70 said:

Since it appears Jan. & Feb. are going to be warmer.  Do you believe it is going to be a very active early severe wax season?  Sorry if this question is in the wrong thread.  Thanks.

Jax and Jeff are the severe folks in our group w janetjanet posting some also from an adjoining forum.  Just a guess(I am no severe wx guru) is that w the extreme cold in Canada combined w the latent heat from the recent super Nino...have to think that is combo for severe wx during spring. Even now, these are big fronts rolling through.  Translate that to spring and that is a recipe for strong storms.  Only a guess.

[weathertree4u]

44 minutes ago, Carvers Gap said:

Weathertree, a few posters outside of our own that I read are ustedtobe, PSU, and bobchill in the MA.  I also read posts by Jon, wow, lookout, and met1985 in the SE forum.  IDK, you may already read their posts, but it is good info for newcomers.  The MA has a great discussion right now about how the ridge post d10 is not static.  

Good suggestions, thanks!

[Carvers Gap]

For the record, I am not saying the Cansips verifies.   Use it as a counter balance to what I said just before I posted those maps. IMO, the pattern switches around mid month...not before but could be a few days later.  Just seems the old pattern should be ending by then.  I don't know that I have model support for that idea, but it is a hunch based on the MJO and where the models try to go.  JB posted this map on a discussion today though I will not rehash his commentary.  Refer to my previous maps about the MJO for correlation to NA weather.   This does give some hope that we enter a new pattern when(if) phases 8, 1, and 2 are reached.  If the MJO takes the "tour" through 3 and 4...it could be a later Jan before the switch.  

[Mrwolf1972]

2 minutes ago, Mrwolf1972 said:

It looks like  Monday cold air gets trapped in the valley with possible snow ice mix before the warm air wins out could be a thought driving couple days.i mean it's not the big storm we wanted but it's a start.

it takes till early Tuesday to move out the cold.

[Carvers Gap]

A storm attacking a retreating cold air mass is something to watch for in the pattern.  Realistic part of the pattern. Only 30+ more runs of the GFS until it gets here.  Waay to early to be talking specifics.  Besides, we have a lighter event to monitor at 108 and a weak low to watch in the GOM at 132 on the 12z Euro.  Not great tracking but better than nothing.

[PowellVolz]

This looks similar to what happened last year in the valley. SE winds banked up against the northern plateau and kept us below freezing almost all day. It was 40ish in Gatlinburg but upper 20's at my house north of Knoxville. The cold was so thick I got more snow than sleet or rz.

Sent from my iPhone using Tapatalk

[jaxjagman]

Euro not that great except TRI..3-4"

Rest of us about   .02-.05

[Carvers Gap]

17 minutes ago, jaxjagman said:

Euro not that great except TRI..3-4"

Rest of us about   .02-.05

Yep.  If even that in reality...most medium range models overdo amounts in the Valley up here in E TN.  If that run were to verify, I would guess that is an elevation dependent snow which is getting lift as it crosses the Apps.  Just watching that unfold on the 12z Euro, I would guess that would have a bit more qpf with it.  It was not a terrible run of the Euro.  Again, it might be worth watching that weak lp in the GOM right after the wave that goes through here.  If the timing is off... there could be more to that.  The good thing is that run of the Euro is beginning to sort-out the crazy, positively tilted trough in the eastern Pacific.  In other words, it has a more realistic evolution of the pattern out there.  

[jaxjagman]

4 hours ago, Carvers Gap said:

Jax and Jeff are the severe folks in our group w janetjanet posting some also from an adjoining forum.  Just a guess(I am no severe wx guru) is that w the extreme cold in Canada combined w the latent heat from the recent super Nino...have to think that is combo for severe wx during spring. Even now, these are big fronts rolling through.  Translate that to spring and that is a recipe for strong storms.  Only a guess.

Couldn't really say right now.ENSO and the PV  would be a good starting point to keep an eye on at this point.Soon as this severe threat early next week exits, i'll start the 2017 severe thread.We don't really need two severe threads going right now,JMO

[John1122]

The ENS are consistently honking a good snow mean for us all. They may be wrong but they are consistent.

[AMZ8990]

Thanks for sharing that john, I hadn't seen that yet.  That is interesting.

[tnweathernut]

18z setup on the GFS is definitely "happy hour".  You can see the difference between 12z with respects to the energy.  (18z robust, 12z says what energy.  This (18z) is a good look for the mid-south.

[Mrwolf1972]

5 minutes ago, Mrwolf1972 said:

 

 

[John1122]

I'd be more excited about the GFS if we had the same thing a few times in a row. As it is there's liable to be a 1050 high blowing everything into Cuba by 00z or it may be an apps runner rainer. 

[tnweathernut]

I know everyone will key on the second system, but for east TN I think the first system is also worth watching.  The GFS bias is for a progressive flow. If it's doing it with the northern branch and the euro is more correct, I think a nice little light snow could happen for east TN.  Digging further west allows the flow to back and precip to break out.  Wouldn't be big, but being a day or two closer (around hour 100) it's close enough to keep an eye on..

[tnweathernut]

3 minutes ago, John1122 said:

I'd be more excited about the GFS if we had the same thing a few times in a row. As it is there's liable to be a 1050 high blowing everything into Cuba by 00z or it may be an apps runner rainer. 

I agree, but the fact it found a robust piece of energy somewhere is encouraging.... let's see if 0z continues with a more robust piece of energy and not so much a strung out mess as depicted on prior modeling.

[Carvers Gap]

1 minute ago, John1122 said:

I'd be more excited about the GFS if we had the same thing a few times in a row. As it is there's liable to be a 1050 high blowing everything into Cuba by 00z or it may be an apps runner rainer. 

I just have to sit back and laugh.  I saw it rolling at 96h and I was like...this ought to be a fun run.  The West coast is just getting mauled this run by precip.   I think back to the rule that says where a storm goes on shore on the West coast it leaves at the same latitude on the East coast.  Doesn't always work, but when southern CA is getting rain...always a good rule of thumb to keep an eye out here during winter.

[weathertree4u]

15 minutes ago, Carvers Gap said:

I just have to sit back and laugh.  I saw it rolling at 96h and I was like...this ought to be a fun run.  The West coast is just getting mauled this run by precip.   I think back to the rule that says where a storm goes on shore on the West coast it leaves at the same latitude on the East coast.  Doesn't always work, but when southern CA is getting rain...always a good rule of thumb to keep an eye out here during winter.

I am so over the GFS, by midnight it will either be gone or rain