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43 minutes ago, tombo82685 said:

Yea, but there is also a delay once epo starts like Tony mentioned. Can start to see it post day 14 cold coming in but they also have it more dumping into plains than gefs do

I thought the delay was about 5 days from the teleconnection switch. I suppose there is the angle of the cold issue also.

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If people don't know as of now, I'm a straight shooter. I will praise my good calls and recognize my bad calls. I was flat out wrong with saying there wasn't a block on the models. I should of worded

You did it wrong  

This was 15 days in advance, not bad AY??

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Not saying this is right or saying there is no cold prior.  From a predicted EPO switch outlook, last night's EPS, GEFS & GEPS did it on the 17th or 18th.  Memory fades, but I think anecdotally there is a 5 day lag for it to get here.  So we are talking 22nd or 23rd, pretty much at the end of the deterministic GFS at this point. The fact that Canada may not be flushed of its relatively warmer air until after the 17th is consistent with the predicted EPO switch.  I think the 06z GFS/GEFS is always run out of Heisey's freezer.    

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10 hours ago, Mitchnick said:

 

I get and don't really disagree with this, but I  guess my point is that the ensemble  snow maps are another tool. Some tools are better than others, but a tool nonetheless. Eps snow from last night took a dive. That tells me that there's a much less "chance" of a snow storm in the next 15 days than was "thought" yesterday based on their most recent run.  And since the mean they are spitting out is less than climo for 1/2 of January,  that's a real good reason to think that is the case. So that's  how I see them. I think that's reasonable.  I just didn't  say all that when I  posted the map. Lol

I get what you're saying, but when you have all these shortwaves floating around nd each run is shifting drastically, those snow maps are wortheless. In a normal case, I agree with your logic. Take 0z last night to 12z today, the ens mean doubled snow amounts in first ten days compared to 0z because it was picking up on one of those shortwaves possbily delivering. If we go off last nights logic though, snow chances are below normal when today says they aren.t 

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I'm starting to wonder if big cold ever comes. I mean you have a flow from flipping nw Alaska here, you would think Barney right?

gfs-ensemble-all-avg-namer-z500_anom-0776800.png.5ec4d0a6543f1b0bf64d468c9f7dbb6d.png

nope 

gfs-ensemble-all-avg-namer-t2m_f_anom_1day-0776800.png.9e7c17e33eb413864f75ea7c59ed289e.png

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Btw, I would not take anything seriously right now past day 7 in long range. To much variability going on. Look at this shift at day 10 on eps, whoops. That was a clear shift towards GEFS who have been showing a deep low in the east. Also look at the shift in the pacific. Went from no Aleutian low to Aleutian low, which in theory if correct should help promote more pna ridging you would think if right. The one stable has been greenland ridging 

ecmwf-ensemble-avg-namer-z500_anom-0841600 (1).gif

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Might be very close to PV split here towards end of euro run. Granted usual caveats here. Gfs has this too at 6z but never goes through fully with split 

 

ecmwf-deterministic-nhemi-z10_anom-0841600.png

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As it gets closer, the mid-Jan period still looks good. As Tom said not that cold, but checks all the boxes for snow here: AO-, NAO-, PNA+, 50/50 supported. Well timed to coldest part of the year. No guarantee of course, but better odds at the craps table.

gfs-ens_z500aNormMean_namer_10.png

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1 minute ago, Chubbs said:

As it gets closer, the mid-Jan period still looks good. As Tom said not that cold, but checks all the boxes for snow here: AO-, NAO-, PNA+, 50/50 supported. Well timed to coldest part of the year. No guarantee of course, but better odds at the craps table.

gfs-ens_z500aNormMean_namer_10.png

yea I mean that h5 look is solid, but it's just wild how you have a flow from NW alaska and can't even get below normal. Is Canada really that deprived of cold air? I mean the flipping tpv is over hudson bay. 

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Probably why the pacific early next week got a little worse, another strong poleward shift in the jet then it settles down for possible retraction for -epo or pna

250hPaJet_prob_1.gif

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The second hit to the pv, that may split it looking stronger than the first one. Hopefully that one will trigger a response to trop

u_65N_10hpa_gefs.png

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00z/7th Ensemble Comparison 1/7-1/22.  Avg normal 850mb temp -4C.  

Canada gets reconfigured late.

GEFS Start Of Teleconnection Forecast Skill:  NAO Day 11; PNA Day 8.5; AO Day 11; Recent Verification Tendency: More Positive NAO & PNA, More Negative AO

GEFS:  (warmer early, then faster cold) Above normal 850mb temp anomalies thru Jan 15th, below normal anomalies Jan 16th thru end of run Jan 22nd.  

GEPS:  (warmer early, then faster cold) Above normal 850mb temp anomalies thru Jan 15th, mainly below normal anomalies Jan 16th thru Jan 20th, above normal anomalies Jan 21st & 22nd.

EPS:  (warmer longer) Above normal 850mb temp anomalies thru Jan 15th, below normal anomalies Jan 16th & Jan 17th, above normal anomalies Jan 18th & 19th, below normal anomalies Jan 20th & 21st.

NAEFS Week 2: Week of January 15th-January 22nd. Weak confidence of above normal temperatures in NJ, strong confidence of near normal temperatures in PA. Toggling back/forth between this and near normal everywhere.

Teleconnections:  (See if you like it better this way vs a snapshot day)

EPS: +EPO, turns negative 1/21; +PNA, turns negative 1/18; -NAO throughout

GEPS: +EPO, turns negative 1/21; +PNA, turns negative 1/17; -NAO approaches neutral 1/22  

GEFS: +EPO, turns negative 1/16; +PNA, turns negative 1/17; -NAO throughout

 

MJO:  (WH Sectors) It is alive! Strongest convection Phase 2.  GEFS Phase 3 to Phase 5 at end; EPS Phase 3 to COD Phase 6 at end (end of outlook 1/21). MVentrice phase 1 (vel potential) reigniting in Phase 6 (looks stronger than it did three days ago) at end.     

MJO phases in January:  4 thru 7 warm, 8 thru 2 cold, 3 transitional.

Strat: NASA Wave 1 slowly weakening to 70th Percentile. Wave 2 Weak, mainly around 10th Percentile. EPS similar Wave 1, stronger Wave 2 at end (reason for more easterlies at 60N?) around 50th percentile.

 

NAM/SPV:  GFS SPV SSW ongoing. Two trofs, second Jan 15th.  GEFS recovery faster January 17th. Other models similar on recovery. Euro similar with two trofs.   GFS does not have Strat coupling; NASA I would say does around the 17th. 

 

Strat is not in my area of expertise.  This looks similar to Jan 2019 (this has nothing to do about snow chances) in which there was a SSW, does it deserve credit for the colder weather and is there colder weather in spite of (predicted for now) MJO going into warmer phases.  There was in 2019.  The -EPO was can kicked.  It is beyond forecast time skill as is the PNA outlooked switch.  Obvious why the GEFS was run out of the freezer, its EPO switch was much earlier.  Regardless all the ensembles are outlooking Canada to turn colder.  For a chunk of this period Canada is still relatively warm.  First, anomalies are not terribly torchy, so whatever does or does not occur next Tuesday, snow could fall with them because it is January.  Second, my dollar cost average with the SSW is Jan 25th.  So really the teleconnection reconfiguring is still beyond model skill time and we will see where we go from here.  I still wouldn't discount later cold.

 

00z/4th Ensemble Comparison 1/4-1/19.  Avg normal 850mb temp -4C.  

GEFS:  (same) Below normal 850mb temp anomalies into Jan 6th, (new colder split(s)) above normal anomalies later Jan 7th into Jan 12th, near normal anomalies night of Jan 12th, mainly above to near normal anomalies Jan 13th into end of run Jan 19th.  Below normal axis is in the  the Plains late shifting from the Southeast earlier. 

GEPS:  (same) Below normal 850mb temp anomalies into Jan 6th (colder splits) above normal anomalies Jan 7th & 8th, near normal anomalies Jan 9th & 10th, mainly above to near normal anomalies Jan 11th thru Jan 17th, (day later) below normal anomalies Jan 18th & 19th.

EPS:  (same) Below normal 850mb temp anomalies into Jan 6th, (same, day later) mainly above normal anomalies Jan 7th thru Jan 12th, (a wash) near normal anomalies Jan 13th thru Jan 18th. Later cold axis slightly farther east than GEFS in Mississippi Valley.

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Look at the persistent nina forcing. We have only had one legit nino cycle into cold phase and that was in august. Did have a weak pass phase 8 that amplified in phase 1/2 back in early nov. Majority of the time it's been crap with subsidence in phases 7/8

 tm_order.png.ef844499e1580b7284bf6fbf771a7341.png

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7 minutes ago, Allsnow said:

We might get mild at the end of next week as the pac Pukes a bit with the reshuffle 

 

06A1538B-173B-43BB-8382-E2C9100A280A.png

5A398951-386C-43B9-963D-048F278153AD.png

I'd bank on it, it's been there for a while on both gfs and euro. Not that it's been bone chilling cold regardless lol

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8 minutes ago, Allsnow said:

Let’s hope we keep the blocking 

9BF0333D-6BE5-4ADA-A9A9-5F1ACA9EC296.png

That’s a pretty tasty looking h5. Heck of a block signal with decent pac 

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6 hours ago, tombo82685 said:

The second hit to the pv, that may split it looking stronger than the first one. Hopefully that one will trigger a response to trop

u_65N_10hpa_gefs.png

trop response looks much better today - bouncy as you know

gfs_nh-namindex_20210107.png

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1 minute ago, Chubbs said:

trop response looks much better today - bouncy as you know

gfs_nh-namindex_20210107.png

That to me looks like it couples just after 15th

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Just now, tombo82685 said:

That to me looks like it couples just after 15th

Its consistent with the AO-/NAO- we are seeing. This has a better feel than the 2019 SSW.

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