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With the IOD at records highs it is one of the main drivers currently . The UKMET keeps it positive all winter. Although it does decline in time. Makes you wonder whether the impact of it can indeed produce an early winter arrival this year.

From a simply persistence point of view, you would have to think the boring and dry period we are having would likely reverse in time, and hopefully coincides with the colder months ahead.

Wonder if maybe the advance posting of the Watch is related to the wording, given the focus on the possible extreme severity of the storm's potential and the wording about setting a new benchmark. Of note to campers and hunters maybe getting caught off guard. Pretty crazy wording ! Extreme impacts possible, including to power infrastructure including power lines resulting in widespread power outages, agricultural interests; outdoor recreational interests including camping and hunting activities; and travel. Widespread significant tree damage is possible with heavy wet snow and strong winds impacting trees with foliage. * ADDITIONAL DETAILS...This early-season winter storm and/or blizzard has the potential to set a new benchmark for snow accumulations, cold temperature

Hoping the QBO continues its decline, seems it may have stalled out in September, possibly related to the SH SSWE and the BDO. Something like this happened before and it then resumed its decline by year end. However, this is a negative at this time, and it really needs to resume its decline to have an effect for the upcoming winter. Some additional comments within this post griteater‏ @griteater Sep 18e The transition from + to - QBO is dropping from the upper stratosphere toward the middle stratosphere. It needs to drop quickly now in order to classify the upcoming winter as -QBO (to go along with the low solar) griteater‏ @griteater Sep 18 More It could be on delay yes, but there’s still a bit of time for it to drop sharply to end the year. In theory, it would be better for winter blocking if it drops sharply (with solar min) 1 reply0 retweets3 likes

Seems the long range GFS is really pushing up the time table we make a full transition to Fall. I would expect a warm rebound of course but maybe the worse of the heat is over after October 3 rd.

The Siberian High off to a good start .

Wonder what March 1 st. to May 1 st would show for the past 5 to 10 year period . I would think a decline maybe . Winters seem to run deeper into the Spring and many times blocking lags and hits in March, April, and sometimes May.

Not sure I buy the extreme heat from the Euro for later next week. Sure dry ground helps but still. That look is unreal over a wide area.

Don S always has some interesting data insights regarding the various indices. This time the focus is the PNA. Although it seems many of his observations recently point to a warm Fall. Well, in my many years of following Don, he simply calls it like he sees it . When the historical associations and data point to colder outcomes he will mention that too. donsutherland1 Location: New York Posted 55 minutes ago The latest PNA forecast shows a dramatic drop that could take place over a very short period of time. Since daily PNA data have been available beginning in 1950, there have been 13 cases where the PNA dropped 3.000 sigma or more during a 5-day period in the September 20-October 10 timeframe. In the New York City region, such a development typically provided a signal that the remainder of meteorological autumn (October and November) would have similar temperature anomalies as September (9/13 or 69% of cases). When it comes to a warm September, as appears very likely this year, 6/8 (75%) cases were followed by a warm anomaly over the October-November period. Both cool cases had cool October anomalies. In short, the PNA appears to be offering a signal that the above normal temperature regime of September will likely predominate during the autumn.

Read in the Mount Holy AFD this AM, but have not looked any further since then, that the GFS had a cool down coming with rain chances later this weekend, while the Euro was continued very warm. Hoping the GFS solution you mention here is the correct one.

Decent Met read looking at the upcoming winter. Courtesy 33andrain OHweather Member Meteorologist 164 36 posts Location: Hackettstown, NJ Posted September 13 Playing with some analogs right now...here are some analogs, discussion, and caveats, focused mainly on the U.S....FWIW, my temp map for work is not as cold as this analog composite would imply and allows some risk for a SE ridge to crop up should things trend too far in the wrong direction (read below). Here are my key assumptions when looking for analogs right now...the analogs used to compile the attached 500mb map were found by subjectively rating every possible analog on each of the following criteria. Ultimately I give ENSO, PDO and QBO the most weight along with the solar cycle, though all of these are considered. ENSO: Neutral, though can allow for weak El Nino or weak La Nina if the year featured warmer waters near the dateline. Extra preference if coming off of a weak or moderate El Nino the prior winter-spring. PDO: Neutral or positive (it's positive right now though not strongly) QBO: Positive trending negative, expecting the 30mb winds to flip to negative at some point in the early to mid-winter Solar: Minimum Indian Ocean: Positive IOD in the fall, can trend downwards during the winter Off-equator Pacific SSTs: A positive to strong positive PMM (it's very positive right now), with more weight given if it stays positive through winter Atlantic: Neutral or positive AMO (it is positive right now though not strongly) Tried to find matches based on similar tropical forcing in mid-late summer as this year, though not as strong of a weight. Tried to find matches based on years with significant spring/summer high-latitude blocking, though was not as strong of a weight. The analogs I went with for this exercise are...1958-59, 1966-67, 1969-70, 1978-79, 1980-81, 1985-86, 1990-91, 1993-94, 1995-96*, 2003-04, 2004-05*, 2013-14*, 2014-15, 2017-18. Stars denote highest scoring matches when considering all of the above and double weighting. Obviously some of these are very cold winters for the eastern U.S. and the composite look is cold. There is a strong signal for Alaskan ridging and a -EPO, which is not a warm pattern for the central and eastern U.S., though where exactly the cold dives in can make a difference for the eastern U.S. with more mixed signals on an NAO. A neutral-ish ENSO and +QBO to start winter aren't great signals for a -NAO, though the deep solar min is and the QBO will be improving through the winter. The SSTs up there support a -NAO, but aren't a strong forcing mechanism on their own. There is not a strong correlation between negative summertime NAO and subsequent winter NAO and the forcing mechanisms are different, so the persistent -NAO this summer doesn't really help or hurt. In terms of what to watch for in the eastern U.S. in terms of swinging warmer or locking in cold...I'll be watching to see if we hang on to the warm waters near the Dateline in the Equitorial Pacific and the +IOD as we head into fall. If we keep those we are more likely to see convection near the Dateline this winter which usually forces an Alaskan/western Canadian ridge. If we see a stronger push towards La Nina and lose the warmth near the Dateline, the risk for a more amped SE U.S. ridge increases...we don't need the Nino region 3.4 anomaly to be above 0C to have a cold winter in the east, but region 4 is pretty important and needs to stay warmer IMO. Based on the persistent -SOI and forecast generally weak trades over the central and western Pacific over the next week or so, there won't be a big La Nina push in the near-term, though the recent easterly trade surge did nudge things in that direction over the last couple of weeks and there's still a lot of time for that to resume. The waters near the Dateline and just west remain fairly warm both at and below the surface, and until that goes away some move back towards a weak Modoki El Nino also can't be ruled out. As we saw last winter, a SSW can really enhance tropical forcing/convection over the West Pac warm pool (which is usually warm for the eastern U.S.), so an initially +QBO and seemingly low risk for an early SSW may give some margin for error...but if the SST pattern becomes unfavorable between Australia and S. America for convection near the Dateline the pattern more likely supports eastern U.S. warmth this winter. The analogs that have an Aleutian low in October generally had much colder subsequent winters than the ones that have an Aleutian high and subsequent trough over western Canada in October. I'm aware of what the longer range guidance hints at to start October up there, but wouldn't lock it in yet. A continued drop of the QBO heading into the fall is also important for increased high-latitude blocking prospects as we head into winter and a lower risk for the Pacific jet to be too strong/zonal into the west coast, which would likely result in quite a bit of warmth for North America given how mild the entire Pacific is. An additional caveat is the northern hemisphere water temperatures from the tropics up to the polar regions where there was another near-record sea ice melt are ON FIRE. Do older analogs break down as we continue to warm? If so, how do things change? The warming baseline gives less margin for error (you probably don't luck into below-average or even average temps, you either have cold signals or you torch). Lots of food for thought...I definitely don't hate the prospects for a snowy winter from the Ohio Valley and Great Lakes into the Northeast, and the warm PMM and any remaining warm ENSO influence can bring some snow prospects to the mountains out west, but the pattern can turn warm quickly if we lose the warm equatorial waters closer to the Dateline.

Really impressive heat ridge building. The typical recent decade era of warm Falls continues, but now so with a more extreme solution possible as some models are forecasting record heights next weekend. To make matters worse, some models now show the WAR as an almost permanent feature in the early Fall and some keep the feature deep in the Fall season. This in a backdrop of growing drought concerns.

Certainly I can see this as a big player, ( Arctic warming, but also how computer modeling is really struggling with winter seasonal outlooks ) . It has been a NH Russian Roulette the last few years. Our region was not lucky but memorable severe snow and cold hit many cities during the winter. So many players on the field, and you have to think extremes are the new normal. https://buffalonews.com/2019/09/18/climate-change-likely-to-throw-wrench-into-winter-outlooks/

Do you think any of these events can be clues of the upcoming Fall season and early winter? Raindance posted in the Nino thread, that a deep -SOI now can lead to possibly cold Decembers.

OMG...... never seen this before. Crazy extreme drop. Jeez.... I really do think as indicators for the late Fall and early winter it is impossible to predict, except to say I feel extremes are in cards in the months ahead.

Some cool info on the Nino thread. Seems negative SOI in September leads to a warm October most times but a cold December. Just one part of the puzzle. Amazing the longevity of the - SOI and the cooling Eastern Pac. Meanwhile courtesy of a recent bluewave post, we have the most poistive ONI yet, MJO forecasted in phase 1 coming up, drop in the NAO and along with a deep and continuing - SOI . Latest Southern Oscillation Index values SOI values for 21 Sep, 2019 Average SOI for last 30 days -14.88 Average SOI for last 90 days -8.63 Daily contribution to SOI calculation -19.49 Monthly average SOI values Jun -9.99 Jul -5.86 Aug -3.14 Note: The SOI values are expressed as an index (i.e. no units) and are derived from the 1887–1989 base period. This information is updated daily. The new data are typically available by 7:00pm (AEST). Daily contribution Date Tahiti (hPa) Darwin (hPa) Daily Contribution 30 day Av. SOI 90 day Av. SOI 21 Sep 2019 1012.89 1013.85 -19.49 -14.88 -8.63 20 Sep 2019 1011.30 1013.65 -27.75 -14.12 -8.62 19 Sep 2019 1010.93 1014.55 -35.30 -13.56 -8.78 18 Sep 2019 1013.89 1015.10 -20.97 -12.84 -8.78 17 Sep 2019 1015.32 1014.55 -9.21 -11.78 -8.76 16 Sep 2019 1015.60 1014.25 -5.76 -11.23 -8.79 15 Sep 2019 1015.15 1014.80 -11.70 -10.79 -8.85 14 Sep 2019 1013.80 1016.00 -26.86 -10.94 -8.81 13 Sep 2019 1013.56 1016.10 -28.88 -10.70 -8.55 12 Sep 2019 1014.46 1016.25 -24.42 -10.34 -8.18 11 Sep 2019 1015.25 1014.90 -11.70 -9.91 -7.91 10 Sep 2019 1014.70 1014.25 -11.11 -9.63 -7.72 9 Sep 2019 1013.50 1014.80 -21.51 -9.19 -7.49 8 Sep 2019 1013.95 1015.15 -20.92 -7.80 -7.03 7 Sep 2019 1014.10 1014.35 -15.27 -6.34 -6.71 6 Sep 2019 1014.09 1013.55 -10.58 -5.17 -6.55 5 Sep 2019 1013.81 1013.60 -12.54 -4.27 -6.55 4 Sep 2019 1013.73 1013.90 -14.79 -3.66 -6.54 3 Sep 2019 1013.36 1013.85 -16.70 -3.23 -6.43 2 Sep 2019 1012.96 1014.15 -20.86 -3.06 -6.33 1 Sep 2019 1013.31 1013.40 -14.32 -2.99 -6.29 31 Aug 2019 1013.01 1013.35 -11.90 -3.00 -6.32 30 Aug 2019 1012.61 1014.40 -20.70 -2.85 -6.22 29 Aug 2019 1014.44 1015.30 -15.05 -2.05 -6.07 28 Aug 2019 1015.17 1014.90 -8.19 -1.22 -6.10 27 Aug 2019 1015.16 1013.85 -1.88 -0.64 -6.12 26 Aug 2019 1014.85 1013.20 0.18 -0.61 -6.17 25 Aug 2019 1014.30 1013.55 -5.28 -0.40 -6.33 24 Aug 2019 1015.25 1014.80 -7.10 -0.03 -6.48 23 Aug 2019 1017.16 1014.85 4.19 0.02 -6.62

Are you saying a cold outbreak ? Wishful thinking right. In winter with longer wavelengths might be interesting . Also did you see the Euro 46 day outlook a lot of snow to drop over Canada in October. Looks to get rather cold up there. Hard to tell if below normal cold though.

Take with a grain of salt, but snow cover to the North builds through October despite the lower 48 very warmish. Can't hurt.

Feedback the real deal, even in late September . this will extend IMHO the summer heat until November Also makes me think twice about over seeding . I mean the entire project is like $ 700 . What to do ?

interesting post from bluewave here it is worth a mention ..... <<<< 10 hours ago, bluewave said: Looks like the more active MJO is shifting us back to a warmer pattern for the rest of September. Much more Niña-like pattern with the big ridge building north of Hawaii. So we are shifting away from the big Canadian high pattern that has dominated since August. Going forward we have to monitor the ridging north of Hawaii. That was one of the factors that spoiled last winter. If this ridge becomes more established north of Hawaii, then that record warm SST blob could shift west with it. Probably too early to know for winter. But just something to monitor going forward. >>>>>

Seems the pattern near Alaska and in the GOA favor that warm blob growing even warmer between now and early October . A very complex Pac as you pointed out.

@bluewave do you see anything out in the long range to change things up in terms of rainfall. And , what do you make of the recent pretty significant drop again in the SOI index.

If you believe his hype and so-called proof it really doesn't matter one way or another, but I still feel it is much better to have a decent cryosphere. I personally don't weight the SAI but I do like to see a lot of snow up North. Last year started great, and then as many of you remember, we lost huge amounts of NA snow cover after the excellent start. I still prefer to see it snow covered than not up North. So that's the reason for this post. A decent start so far.

I like this very much and could help us here. Maybe forcing will be dateline centered, while the Eastern Pac cools off.

Some hang the hat on the negative GLAAM Personally I think its a marketing move here. And I love the part about the low confidence