Jump to content
  • Member Statistics

    17,507
    Total Members
    7,904
    Most Online
    SnowHabit
    Newest Member
    SnowHabit
    Joined

Winter 2020-21 Discussion


CAPE
 Share

Recommended Posts

1 hour ago, Rhino16 said:

I wasn’t seeing how anyone thought it could be a Modoki... it looked east-based to me. Maybe I need to go back and look at previous years...

The models are showing it becoming a modoki as we go into winter. Most Ninas start east and move west. Right now, it’s definitely a basin-wide event, all 4 ENSO regions are cold. ENSO region 4 has not been this cold (-0.6C) in well over a decade. The models show region 4 remaining cold throughout the winter. nino4.pnghttps://tropicaltidbits.com/analysis/ocean/nino4.png

Link to comment
Share on other sites

This is similar to the nino debate a few years ago. Some define enso type by its origin and evolution while some by simply a snapshot of sst anomalies at any given point. Based on what I’ve seen and the fact there is often a lag on sensible impacts to the global pattern I tend to be in the first camp.  But that’s my opinion. What annoys me is when the competing classifications create confusion and stupid heated arguments because of it. 

Link to comment
Share on other sites

Current SST anomalies are interesting, imo.  Though the PDO clocked in at -1 for Sept it did rise from its Aug reading of -1.3.  I understand the current state of anomalies are bound to change but if we can manage to keep some semblance of the current look as we enter Dec it would be at least encouraging.  The warm water along the west coast, coolish pool where we are used to seeing the blob and an east based (up for debate :D) nina.  To me it looks close to '95 right now....just the warms are warmer. Sept of 95 had a +pdo...must be 2020's lack of cool anoms to the east of Japan?

pL0w8Mm.png

  • Like 1
  • Haha 1
Link to comment
Share on other sites

 

Similar to last year,  the Chukchi Sea presently has extremely low sea ice extent. . This my have some role in our late Fall weather. 

 

 

Another thing to look for regarding clues to the upcoming winter is what phase(s)  the MJO mostly travels in during the month of October.  

 

79D9EBBB-8E6A-4BAC-A243-D0B927E6566D.gif.79282a5c1c4e64ef23c1be06bf049c5f.gif

 

As bluewave and Don S. have referenced there appears to be a connection to the following winter's  EPO and AO state. 

From Don S. 

<

In addition, from the larger pool of La Niña winters following El Niño winters, there were four cases where October saw the MJO in Phases 4-6 for 20 days or more: 1983-84, 1988-89, 1998-99, and 2016-17. All four cases featured an EPO+/AO+ winter. Three cases saw the MJO in Phases 4-6 for less than 20 days: 1995-96: 12 days, 2007-08: 6 days, and 2010-11: 6 days. Both 1995-96 and 2010-11 featured a predominantly negative AO. The latest ensemble guidance favors October 2020 falling into the former pool. Among that pool, October 1983 and 2016 featured above normal and near normal rainfall respectively. October 1988 and 1998 saw below normal and much below normal rainfall respectively.  

>

Meanwhile the West Pac warm pool appears to be at near record temps. If you recall there was a study posted last winter 

https://www.nature.com/articles/s41586-019-1764-4

Here is a tidbit from the abstract. 

Here we show that rapid warming over the tropical oceans during 1981–2018 has warped the MJO life cycle, with its residence time decreasing over the Indian Ocean by 3–4 days, and increasing over the Indo-Pacific Maritime Continent by 5–6 days. We find that these changes in the MJO life cycle are associated with a twofold expansion of the Indo-Pacific warm pool, the largest expanse of the warmest ocean temperatures on Earth. The warm pool has been expanding on average by 2.3 × 105 km2 (the size of Washington State) per year during 1900–2018 and at an accelerated average rate of 4 × 105 km2 (the size of California) per year during 1981–2018. 

 

 

Link to comment
Share on other sites

3 hours ago, frd said:

 

Similar to last year,  the Chukchi Sea presently has extremely low sea ice extent. . This my have some role in our late Fall weather. 

 

 

Another thing to look for regarding clues to the upcoming winter is what phase(s)  the MJO mostly travels in during the month of October.  

 

79D9EBBB-8E6A-4BAC-A243-D0B927E6566D.gif.79282a5c1c4e64ef23c1be06bf049c5f.gif

 

As bluewave and Don S. have referenced there appears to be a connection to the following winter's  EPO and AO state. 

From Don S. 

<

In addition, from the larger pool of La Niña winters following El Niño winters, there were four cases where October saw the MJO in Phases 4-6 for 20 days or more: 1983-84, 1988-89, 1998-99, and 2016-17. All four cases featured an EPO+/AO+ winter. Three cases saw the MJO in Phases 4-6 for less than 20 days: 1995-96: 12 days, 2007-08: 6 days, and 2010-11: 6 days. Both 1995-96 and 2010-11 featured a predominantly negative AO. The latest ensemble guidance favors October 2020 falling into the former pool. Among that pool, October 1983 and 2016 featured above normal and near normal rainfall respectively. October 1988 and 1998 saw below normal and much below normal rainfall respectively.  

>

Meanwhile the West Pac warm pool appears to be at near record temps. If you recall there was a study posted last winter 

https://www.nature.com/articles/s41586-019-1764-4

Here is a tidbit from the abstract. 

Here we show that rapid warming over the tropical oceans during 1981–2018 has warped the MJO life cycle, with its residence time decreasing over the Indian Ocean by 3–4 days, and increasing over the Indo-Pacific Maritime Continent by 5–6 days. We find that these changes in the MJO life cycle are associated with a twofold expansion of the Indo-Pacific warm pool, the largest expanse of the warmest ocean temperatures on Earth. The warm pool has been expanding on average by 2.3 × 105 km2 (the size of Washington State) per year during 1900–2018 and at an accelerated average rate of 4 × 105 km2 (the size of California) per year during 1981–2018. 

 

 

This record low Arctic sea ice is disturbing. I think it’s definitely a contributing factor to the ++AO winters we’ve been seeing the last few years. It seems to be causing a positive feedback loop 

Link to comment
Share on other sites

20 minutes ago, midatlanticweather said:

GFS looks like it wants to ramp up the snow in Siberia over the next two weeks. Let's see how it really goes.. SAI has not proven much help the last few years from what I can tell.

 

I don’t even bother looking at the SAI anymore. It’s proven to be completely useless snake oil. Abysmal failure several winters in a row 

Link to comment
Share on other sites

8 hours ago, snowman19 said:

We are about to start seeing a fully coupled, ocean-atmosphere Niña start to take shape in the next few weeks. Should be interesting to see how that affects the PDO: 

 

Oh sure, so the nina this year can couple, but the niño of 18'-19', for whatever reason, couldn't...offfffffcourse, lol :rolleyes:

Link to comment
Share on other sites

4 hours ago, Maestrobjwa said:

Oh sure, so the nina this year can couple, but the niño of 18'-19', for whatever reason, couldn't...offfffffcourse, lol :rolleyes:

The atmosphere has been screwy since the 15-16 super El Niño event, it obviously altered the global circulation in a big way. Don’t look at the new Euro seasonal for winter, ugly is putting it nicely, it made the new CANSIPS look good, but wow at this Euro run.....

Link to comment
Share on other sites

1 minute ago, snowman19 said:

The atmosphere has been screwy since the 15-16 super El Niño event, it obviously altered the global circulation in a big way. Don’t look at the new Euro seasonal for winter, ugly is putting it nicely, not that the new CANSIPS was good, but wow at this Euro run.....

That Euro outlook is a Spring outlook - it may be winter months, but it looks warm for sure.

 

Link to comment
Share on other sites

17 minutes ago, midatlanticweather said:

That Euro outlook is a Spring outlook - it may be winter months, but it looks warm for sure.

 

At least it would be nice a lot.  We probably have very few days with a high below 50 if that’s correct. And likely quite a few 60+ days. And at least we wouldn’t waste time on false hope. Snow would be 500+ miles away not teasing us. We could just accept it won’t snow at all and enjoy an extended October all winter. 

  • Like 2
Link to comment
Share on other sites

1 minute ago, psuhoffman said:

At least it would be nice a lot.  We probably have very few days with a high below 50 if that’s correct. And likely quite a few 60+ days. And at least we would waste time on false hope. Snow would be 500+ miles away not teasing us. We could just accept it won’t snow at all and enjoy an extended October all winter. 

I am down for this. Need to get acclimated to the new normal. Resistance is futile.

  • Like 1
  • Haha 1
Link to comment
Share on other sites

11 hours ago, psuhoffman said:

Euro is a carbon copy of last winter. Maybe even worse.  Ridiculous central pac ridge, AK vortex, raging +NAO. 

I took a peek at the monthly h5 means posted in the NE thread. December isn't that bad, with a west based -NAO, and the Pac ridge s/w of the Aleutians' has not yet become an absolute monster. Most likely the NAO would just keep us from torching, but if that PAC ridge is not yet a fixture and/or is positioned a bit further NE, ya never know. Verbatim that would probably produce for central and northern NE.

Link to comment
Share on other sites

This is probably the sort of look we have to "hope" for. Latest CFS h5 mean for December. Maybe if the PDO goes positive it can aid in sustaining an early winter PNA-ish ridge for a while before the pattern retros and turns to complete suckage. Just a bit of help up top here too. Fwiw, CFS looks decent for Jan as well. All the usual disclaimers apply.

cfs-mon_01_z500a_namer_2.png

Link to comment
Share on other sites

2 hours ago, CAPE said:

I took a peek at the monthly h5 means posted in the NE thread. December isn't that bad, with a west based -NAO, and the Pac ridge s/w of the Aleutians' has not yet become an absolute monster. Most likely the NAO would just keep us from torching, but if that PAC ridge is not yet a fixture and/or is positioned a bit further NE, ya never know. Verbatim that would probably produce for central and northern NE.

Yea, in that Euro run, December would definitely be the “better” month. You’re correct that we’d avoid an all out torch with the -NAO, which we’d have given the Pacific look (-PNA/RNA, +EPO). People didn’t like December because of the Pacific side it shows, the EPO and PNA floodgates are going to be open. Then it obviously goes all to hell for Jan and Feb

Link to comment
Share on other sites

I've just been doing some little looks at things but it appears this winter will be entrenched in a La Nina pattern. From what I see in our history, we can still get cold weather during La Nina, but substantial snow is very hard to come by unless you just get the perfect ingredients, like in 93. Is that fairly accurate?

Link to comment
Share on other sites

Funny, the euro has this winter forecasted to turn out the same as last winter yet had the opposite forecast this time last year.  Though, maybe the climate  models have a better chance at being somewhat accurate with what looks like a typical atmospheric response to the current enso state...unlike last year.  

I am fully prepared for fluke hunting this season. Whatever. Work is pouring in and a mild winter would be extremely helpful. 

Link to comment
Share on other sites

2 hours ago, Rhino16 said:

Does the color shading mean much on those charts, or do the contours matter more?

They both "mean something". You have to keep in mind it is a super LR mean- a monthly mean at that. I pay more attention to the height anomalies on these panels, as it is indicative of  where the features of interest may set up in general. Outside of a super blocked up pattern though, clearly there will be some shifts in the location and intensity of the + and -height anomalies.

Link to comment
Share on other sites

12 hours ago, CAPE said:

This is probably the sort of look we have to "hope" for. Latest CFS h5 mean for December. Maybe if the PDO goes positive it can aid in sustaining an early winter PNA-ish ridge for a while before the pattern retros and turns to complete suckage. Just a bit of help up top here too. Fwiw, CFS looks decent for Jan as well. All the usual disclaimers apply.

cfs-mon_01_z500a_namer_2.png

Problem is we need so much to go right to cash in much before Xmas. A “decent” pattern is likely to be wasted wrt snowfall. If we only get one mediocre look December is the worst month to get it. 

Link to comment
Share on other sites

1 minute ago, psuhoffman said:

Problem is we need so much to go right to cash in much before Xmas. A “decent” pattern is likely to be wasted wrt snowfall. If we only get one mediocre look December is the worst month to get it. 

True, but it does happen. Remember the NC snowstorm a few years ago while we were smokin' cirrus?

Link to comment
Share on other sites

23 minutes ago, CAPE said:

True, but it does happen. Remember the NC snowstorm a few years ago while we were smokin' cirrus?

True but we did still waste what was a pretty good 3 week period from late November to mid December.  We had a few cold rain events that would have been snow in January.  Then when we did get a shot of true arctic air into the pattern we missed the one true threat. End result was nothing to show for a pattern that likely would have produced some snow in mid winter!  But I’m not saying we can’t snow significantly in December. It sometimes happens. But if we look at the history of the “cold December Nina’s” most were more frustrating than celebratory with mostly minor snows that would leave us feeling unfulfilled when the winter torch comes. I’m purely going by the probabilities based on past results. 

Link to comment
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
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...