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Winter 2014-2015 Pattern Discussion Thread II

JoshM

By JoshM,
in Southeastern States

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SnowGoose69

SnowGoose69

Posted
Posted

New project: I've just decided to calc. the mean anomaly for KATL for each of phases 6-8 in Jan 1975-2014. Wish me luck lol. See you in a couple of hours.

 

Doing my climo work today...unless the morning of 12/31 ruins it (which it might) ATL Should see their fewest ever 32 or lower min temps ever in December at a measly two...1984 had 3 and 2012 had 5.  My guess is some other warmer Decembers would have had 2 or 3 but the urbanization of the area to the N and NW in the last 20 years has resulted in the airport at a slightly higher elevation no longer radiating as well on nights with light N-NW flow as they used to.

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SnowGoose69

SnowGoose69

Posted
Posted

It would be funny if November ended up colder than Dec, Jan, and, Feb. Has that ever happened ? Also, it would be funny if my lowest temp this winter (16) ends up occurring in November.

 

I think that would be impossible, I did see there were 2 incidents since 1970 where December was warmer than November at ATL but cannot remember which years, I want to say it was 1971 and 1984 but cannot remember...you can absolutely see your lowest min for the winter be in November but I doubt you can get all 3 winter months to average less than November this year, if you had a 1976 type November than maybe.

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Snowless in Carrollton

Snowless in Carrollton

Posted
Posted

I think that would be impossible, I did see there were 2 incidents since 1970 where December was warmer than November at ATL but cannot remember which years, I want to say it was 1971 and 1984 but cannot remember...you can absolutely see your lowest min for the winter be in November but I doubt you can get all 3 winter months to average less than November this year, if you had a 1976 type November than maybe.

I believe this Dec is in danger of being warmer than Nov. I could be wrong though. Also, Feb is typically warmer than Dec so I would imagine there's at least a chance Nov ends up colder than Dec and Feb. Not sure about Jan though since that is usually our coldest month.
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GaWx

GaWx

Posted
Posted

I believe this Dec is in danger of being warmer than Nov. I could be wrong though. Also, Feb is typically warmer than Dec so I would imagine there's at least a chance Nov ends up colder than Dec and Feb. Not sure about Jan though since that is usually our coldest month.

 

 This Dec. will end up warmer than Nov. By ~1 F.

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Cold Rain

Cold Rain

Posted
Posted

Fluke man on the x files came out of the crapper..or at least where the crapper empties, and it was a surprise. Don't be so quick to empty out the bowels of fun upcoming. 3 days out is about all you can rely on model wise to make you feel regular, so I still think a New Years Eve or around surprise can release the pent up frustrations, lol. Can't ever discount all this rain running underneath, and more in the next day or so. I had rain for 3 or 4 days, then cold enough for two...if either of the two had sped up or slowed down there wouldn't be this pervasive irregular feeling going on. We had it a lot better back in the old days when we didn't have models to tell us how to think. We just had to wait and see, and it was always fun to go sledding on the weatherman's 3 day projection of partly cloudy and cool, lol. T

Tony, that's just a funny post all the way around man!

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Webberweather53

Webberweather53

Posted
Posted

1) I agree for many here. However, I also care about all aspects including exciting ups and downs of temp.'s as well as IP/ZR and even cold rains. Nearly half of ATL major winter storms have been ZR's.

 

2) Folks,

  I recommend you pay attention to the phase 6-8 Jan maps just posted by Webber. Yes, there have been a number of exceptions to the rules for MJO phases (cold vs. warm in the SE) as I've noted. However, fwiw, these maps at least suggest a rather strong signal for -AO/-NAO for 6-8 (ETA for 6 ~1/9) and a solid +PNA (note the western ridging/E troughing)/Aleutian low for 7-8 (ETA for 7, if we make it there, ~1/15), which we desperately need:

 

attachicon.gifDec-vs-Jan-MJO-Phase-6-8-500mb-1024x594.jpg

 

Webber, do you know the ~number of days covered by each of these Jan phases in these maps? What years, etc.? Obviously, the more, the more credible. 

 

Thanks, Webber, I think I got it. Come on, phase 6! Mods are suggesting that will start near 1/8-10. Also, look at those beautiful +PNA phase 7/8 500 mb maps for Jan! I know they're just mean

maps, but that may very well be the ticket. 1/15 or bust ! ;)

 

That's the spirit! It's certainly nice to see you've become quite interested by the MJO & AO connection... Allan Huffman knows for sure the exact number of days used in his composites, but if you want to see the number of days used go the link I provided below this paragraph. I just used the "all amplitude composites", which is useful for expanding the sample size examined (however, this still results in MJO days being recorded that are within the COD, thus further stratification into days w/ >1.0 amplitude may be necessary, though this the does not dramatically alter the relationship that Phase 6-8 MJO events in January are more effective @ leading to -AO bursts vs Phase 6-8 MJO events in December...)

 

RMM values June 1, 1974 to present

http://cawcr.gov.au/staff/mwheeler/maproom/RMM/RMM1RMM2.74toRealtime.txt

 

If you or any other bloggers want to learn more about the physical connection between the MJO, the AO, NAO, PNA, etc. these papers are well worth your time to read...

 

Before going through these papers below, I think it would be important to go through this paper, it will give you a very strong foundation & understanding of the MJO, I've personally read through it about 6-7 times in the past few years & I absolutely love it...

https://www.rsmas.miami.edu/users/czhang/publications/MJOrev.pdf

 

"The Boreal Winter Links between the Madden Julian Oscillation and the Arctic Oscillation"

http://journals.ametsoc.org/doi/pdf/10.1175/2007JCLI1955.1

 

"The Interaction of the Madden-Julian Oscillation and the Arctic Oscillation"

http://journals.ametsoc.org/doi/pdf/10.1175/JCLI3251.1

 

"The Impact of the MJO on clusters of wintertime circulation anomalies over the North American region"

http://www.meteo.psu.edu/~sbf1/papers/Riddle.etal.pdf

 

An Observed Connection between the North Atlantic Oscillation and the Madden-Julian Oscillation

http://journals.ametsoc.org/doi/pdf/10.1175/2008JCLI2515.1

 

"Tropical-extratropical interactions" Paul E. Roundy (One of the creators of the RMM MJO index)

http://www.atmos.albany.edu/facstaff/roundy/convection/Walich14.pdf

 

A few interesting tidbits of information from this aforementioned paper that I think deserve special attention. 

 

Page 501

"The extratropical patterns associated with the MJO vary dramatically in both phase and amplitude with the status of ENSO and its temporal trend, as illustrated by the finding that composite signals in extratropical circulation associated with the MJO are substantially and significantly larger and found in different geographical locations when MJO events included in the averages are further sorted according to the ENSO phase in which they occur (Roundy et al. 2010)."

 

"During development of La Nina conditions, high- amplitude expressions of RMM 6 and 7 are relatively infrequent, whereas phases 2–5 occur more often. Since the structure of the MJO and its associated global patterns change with ENSO (Roundy et al., 2010)... "

 

 

Figure 14.3 from page 502 shows the Rossby Wave Train that emanates from anomalous heating/convection associated with the MJO when it approaches the dateline (MJO phases 7,8, & 1), w/ each dotted & lined contour area corresponding to anomalous subtropical & extratropical pressure anomalies (which because the attendant upper level divergence & mid-latitude jet are to the north of the mean MJO signal, the Coriolis Force deflects this northward moving perturbation imparted by the MJO increasingly to the right w/ continual increases in latitude. These pressure anomalies are then thereby reflected onto a broad spectrum of familiar extratropical teleconnections, including but not limited to the PNA, AO, NAO, TNH, EPO, etc...

 

This Rossby Wave Train is a primary element that binds together the intraseasonal forcing from the MJO & a myriad of convectively coupled equatorial waves to our sensible weather & teleconnections observed here in the mid-latitudes, thus it's important for researchers & even weather enthusiasts alike to understand the role the Rossby Wave train in part by the MJO plays on our weather on timescales that are somewhat independent of lower frequency variance from the AMO, PDO, ENSO, etc...

Rossby-Wave-Train-Pacific-MJO-Internatio

 

Notice the striking similarities between Rossby Wave Train induced by the MJO & that enforced by recurving Western Pacific Typhoons, the actual physical mechanisms involved are approximately equivalent, their main separation has to do w/ the timescales each variable operates on...

West-Pacific-typhoon-teleconnection-expl

 

Here's a few important quotes from this relatively short paper by Dr. David M Straus & Dr Jagadish Shukla that is worth putting in the back of your mind 

http://www.onr.navy.mil/reports/FY13/mmstraus.pdf

"Recent evidence suggests more clearly that the intra-seasonal variability of the atmospheric circulation in the North Atlantic, and in particular the North Atlantic Oscillation (NAO), is impacted by tropical convection related to the phase of the Madden-Julian Oscillation (Cassou 2008; Lin et al. 2009)"

 

 

"...roughly 10-15 days after the convection peaks in the Indian Ocean, the phase of the NAO with the enhanced high-latitude low (enhanced Atlantic jet), here called the NAO+ becomes significantly positive. This agrees with the observationally based analysis of Cassou (2008), carried out using a multi-variate principal component analysis for the MJO and a cluster analysis for 500 hPa heights."

 

 

New project: I've just decided to calc. the mean anomaly for KATL for each of phases 6-8 in Jan 1975-2014. Wish me luck lol. See you in a couple of hours.

 

 

Oh, you'll be gone for more than just a few hours after sifting through these papers I've listed above :)

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GaWx

GaWx

Posted
Posted

Doing my climo work today...unless the morning of 12/31 ruins it (which it might) ATL Should see their fewest ever 32 or lower min temps ever in December at a measly two...1984 had 3 and 2012 had 5.  My guess is some other warmer Decembers would have had 2 or 3 but the urbanization of the area to the N and NW in the last 20 years has resulted in the airport at a slightly higher elevation no longer radiating as well on nights with light N-NW flow as they used to.

 

 Wow!

 Well, it at least won't be the warmest Dec. min. Not only have there been several with coldest of 30, 1931 (at least) had a coldest of 31.

 Aside: 1908 had a Dec lowest of 30 and a lowest of 8 that following Jan!

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GaWx

GaWx

Posted
Posted

 I'll need a lot more time to calc. the avg. temp. anomaly at KATL 1974-2014 in Jan for each of MJO phases 6-8 (amplitude >1). However, I do have some prelim. more general phase 6-8 info for Jan (amp. >1) since 1974:

 

1) Each of the 3 phases lasted an avg. of ~5 days when it actually was in a particular Jan.

 

2) Longest consec. days in Jan.: phase 6: 11; phase 7: 17; phase 8: 13

 

3) % of Jan.'s with each phase:

6: 65%

7:60%

8: 53%

 

4) Only 23% of Jan.'s had no phases 6-8.

Only 1/3 of Jan.'s had no phases 7-8, the good phases.

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max100

max100

Posted
Posted

Maybe a new typhoon possibly NOW developing near the Philippines will re-curve and shake the sh## out of the atmosphere.

NASAHurricane ‏@NASAHurricane 7m7 minutes ago

NORTHWESTERN PACIFIC OCEAN -System 99W appears ripe for development and on a track to the southern Philippines.... http://fb.me/3sYfEk72o

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SnowGoose69

SnowGoose69

Posted
Posted

lol its not raging. What sucks is they are both negative now and we got nothing. 18z gefs retros the epo ridge to Siberia.

 

Thats the transient period I posted about either here or in some other forums...the 1/8 to 1/15 period is going to get scary for many...ironically I think you guys may be colder in that period than you will in the next 10 days because I think the SE ridge is going to get booted as the EPO ridge either repositions or temporarily weakens, so while Chicago or NYC may average +5 in that week it may only average +2 in RDU ATL or GSP...after 1/15 I think we will see a more typical Western ridge build which will result in a classic eastern US Trough.

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franklin NCwx

franklin NCwx

Posted
Posted

Thats the transient period I posted about either here or in some other forums...the 1/8 to 1/15 period is going to get scary for many...ironically I think you guys may be colder in that period than you will in the next 10 days because I think the SE ridge is going to get booted as the EPO ridge either repositions or temporarily weakens, so while Chicago or NYC may average +5 in that week it may only average +2 in RDU ATL or GSP...after 1/15 I think we will see a more typical Western ridge build which will result in a classic eastern US Trough.

is the se ridge all from the mjo?
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Cold Rain

Cold Rain

Posted
Posted

Thats the transient period I posted about either here or in some other forums...the 1/8 to 1/15 period is going to get scary for many...ironically I think you guys may be colder in that period than you will in the next 10 days because I think the SE ridge is going to get booted as the EPO ridge either repositions or temporarily weakens, so while Chicago or NYC may average +5 in that week it may only average +2 in RDU ATL or GSP...after 1/15 I think we will see a more typical Western ridge build which will result in a classic eastern US Trough.

Goose, it can't get any scarier than it is right now. This winter is going to be the biggest fail I'm the history of weather boards, or it's going to turn around pretty soon. Currently, it looks like the former. Not sure how it gets much worse than that lol! Personally, I think business picks up mid month.

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SnowGoose69

SnowGoose69

Posted
Posted

Goose, it can't get any scarier than it is right now. This winter is going to be the biggest fail I'm the history of weather boards, or it's going to turn around pretty soon. Currently, it looks like the former. Not sure how it gets much worse than that lol! Personally, I think business picks up mid month.

It'll be scary since the next 10 days as a whole will average below normal in a good part of the lakes Ohio valley and northeast so when it suddenly moderates again the WTFs will be rampant

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Webberweather53

Webberweather53

Posted
Posted

It's sad to see so many already giving up on winter, obviously my bit about the fact that we still have ~85-90% of winter left to go here in central NC didn't strike too many chords (RDU is certainly a viable proxy)... Just as a reminder, El Nino Januarys & Februarys have the largest number of NESIS storms per capita, and I should mention that 8 of Columbia, SC's top 10 all-time snows (including the top 4) have come in February, 7 out of 10 for Augusta, GA. That's not just a coincidence...

http://www.weather.gov/cae/Snowfall_Total_Records_cor.html

 

Climatologically speaking, about 45-50% of Columbia SC's snowfall comes in February, and it is the snowiest month of the winter in both climatology & +ENSO years. I have found some of the cliff jumping of late to be quite hilarious, it's statistically equivalent to to claiming the Atlantic hurricane season is over in early August, lol...

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franklin NCwx

franklin NCwx

Posted
Posted

It's sad to see so many already giving up on winter, obviously my bit about the fact that we still have ~85-90% of winter left to go here in central NC didn't strike too many chords (RDU is certainly a viable proxy)... Just as a reminder, El Nino Januarys & Februarys have the largest number of NESIS storms per capita, and I should mention that 8 of Columbia, SC's top 10 all-time snows (including the top 4) have come in February, 7 out of 10 for Augusta, GA. That's not just a coincidence...

http://www.weather.gov/cae/Snowfall_Total_Records_cor.html

Climatologically speaking, about 45-50% of Columbia SC's snowfall comes in February, and it is the snowiest month of the winter in both climatology & +ENSO years. I have found some of the cliff jumping of late to be quite hilarious, it's statistically equivalent to to claiming the Atlantic hurricane season is over in early August, lol...

it happens every year. Just wait till late January/February when a storm is coming and the sun angle ground temp crowd comes out and fills up a couple pages.
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Webberweather53

Webberweather53

Posted
Posted

it happens every year. Just wait till late January/February when a storm is coming and the sun angle ground temp crowd comes out and fills up a couple pages.

 

Oh I know... I think it's cool to see that at least Brick certainly knows better than to fall for this seasonal trap & is actually voice of reason in this case

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packbacker

packbacker

Posted
Posted

Oh I know... I think it's cool to see that at least Brick certainly knows better than to fall for this seasonal trap & is actually voice of reason in this case

 

brick has turned into a good poster this year.

You two will join the dark side soon enough :-)

You have to admit that you were not expecting the first 6 weeks of winter for central NC to be +3 to +4F, with a solid +AO/NAO, and the entire east coast well below average for snow? Let's face it DJF isn't going to average a negative temp anomaly, which I know isn't important but nobody was expecting that.

To be honest I will be more surprised if we finish at climo for snow. I don't think we will get skunked.

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