Winter 2012-2013 General Discussion

[Jonger]

so true.

In other news...its looking like the chances of a mod/strong Nino are getting slimmer and slimmer. A weak Nino would be perfect for our region. I will go with winter of 2012-13 falling somewhere between "better than 2011-12" and "flat out awesome".

I would like to see a sustained cold winter much more than a rollercoster... Give me average snow and consistent snow cover.

[Jonger]

This so lacks a basic understanding of how weather works, that its ALMOST not funny!

March is far more then 4 degrees warmer then January and it can surpass that months snow total without any trouble.

[wisconsinwx]

March is far more then 4 degrees warmer then January and it can surpass that months snow total without any trouble.

One of the bigger points he's missing is he's just talking about the highs. Who says it can only precipitate during the middle of the day? Many of our best snowfalls are at night, obviously on those days the temps overnight will be below freezing, probably well below.

[Powerball]

Normal high for me is 29 in mid January. Get a +4 temp departure going and that changes fluffy white snow into nice liquid rain. So anomalies do matter.

lol.

[michsnowfreak]

One of the bigger points he's missing is he's just talking about the highs. Who says it can only precipitate during the middle of the day? Many of our best snowfalls are at night, obviously on those days the temps overnight will be below freezing, probably well below.

Not to mention, its never snowed at 33F before? LOL areas have gotten buried in record heavy, wet snow where the temps have never fallen below 33F. And as you said, a max temp of 33F on most days would imply that the temperature was AOB 32F for 22-23 of the 24 hours in the day. I get the constant trolling saying its going to be a torch forever and ever, thats his thing, but the +4 departure turning snow to rain is the dumbest post ever. This is almost enough to take ones troll card away!

[Geos]

One of the bigger points he's missing is he's just talking about the highs. Who says it can only precipitate during the middle of the day? Many of our best snowfalls are at night, obviously on those days the temps overnight will be below freezing, probably well below.

That post is epic! Lol. Some of the best and problematic snows fall at 33. Most of the day would be below freezing. Your points above are spot on.

[wisconsinwx]

That post is epic! Lol. Some of the best and problematic snows fall at 33. Most of the day would be below freezing. Your points above are spot on.

Yeah, it doesn't take a ton of ingenuity to tear some of his posts apart. Sadly for him, with this summer being so warm, even a slightly warmer than normal winter will be a huge shock to his system and he'll have to move to Florida probably lol.

[A-L-E-K]

I'm still not into long range forcasting but for S&Gs...I think we'll see a continuance of the anomalous weather of the past few years. There's increasing evidence that artic sea ice decline is leading to warmer falls and I suspect we'll see heat records threatened/broken well into the fall. Definitely going to go with a wetter winter than last...as to whether that's liquid or white will depend on, you know, the weather.

[cyclone77]

I'm still not into long range forcasting but for S&Gs...I think we'll see a continuance of the anomalous weather of the past few years. There's increasing evidence that artic sea ice decline is leading to warmer falls and I suspect we'll see heat records threatened/broken well into the fall. Definitely going to go with a wetter winter than last...as to whether that's liquid or white will depend on, you know, the weather.

I thought you were gonna say the +4 temp departure.

[daddylonglegs]

Want to try winter camping this year...maybe 2 or 3 days...try to do it with temps that aren't outrageously cold (maybe 20Fs)... I'm watching "Survivorman" (its back) and he's in Norway (winter) and it just looks like it would be fun (if you are properly prepared...lots of food!). I'd just use a tent and a very warm sleeping back and about 20 layers of clothes...

Anyone winter tent/igloo camp before?

[daddylonglegs]

Tropical-

Don't cover those palms this winter...with how warm its going to be (probably 50Fs near the lake all Jan with 80F lake temps)...trust me... :)

[IWXwx]

Want to try winter camping this year...maybe 2 or 3 days...try to do it with temps that aren't outrageously cold (maybe 20Fs)... I'm watching "Survivorman" (its back) and he's in Norway (winter) and it just looks like it would be fun (if you are properly prepared...lots of food!). I'd just use a tent and a very warm sleeping back and about 20 layers of clothes...

Anyone winter tent/igloo camp before?

Not me, but my brother-in-law has done it a few times. He seems to enjoy it. If you have some specific questions I can relay.

[Geos]

I'm still not into long range forcasting but for S&Gs...I think we'll see a continuance of the anomalous weather of the past few years. There's increasing evidence that artic sea ice decline is leading to warmer falls and I suspect we'll see heat records threatened/broken well into the fall. Definitely going to go with a wetter winter than last...as to whether that's liquid or white will depend on, you know, the weather.

I think the decrease in Arctic sea ice could be part of the problem, but not entirely. How much difference is there really between ice that is just below freezing and water that is near freezing all year round? Not much really. I will say with ice, sunlight is obviously reflected more off of the ice vs. the ocean. I think the biggest effect on our regional temperatures would be early in the Autumn when there is still sunlight hitting the Arctic Ocean. Once we get well into October sea ice is growing and snow is fall above the Arctic Circle.

This year the Bearing Sea broke up really late and snow and ice were really persistent in places further north, but of course that didn't result in any cooler air here.

The stagnant high pressure that has been parked over the continent for the better part of the year is definitely the culprit since March when things locked up during the March torch. That helped lead to the drought, which heating things up more.

I think the decrease in sea ice has lead to more moisture in the atmosphere of the NH. That could be what contributed the recent strong of snowy winters across the region - at least partly the reason. They've been milder, but with more snow... and rain at times. Less sea ice in the early in the season should lead to more snows in the arctic and subarctic, which should lead to a substantial build up of cold air if we have a cooperative AO this winter ~ and jet stream.

[KokomoWX]

Want to try winter camping this year...maybe 2 or 3 days...try to do it with temps that aren't outrageously cold (maybe 20Fs)... I'm watching "Survivorman" (its back) and he's in Norway (winter) and it just looks like it would be fun (if you are properly prepared...lots of food!). I'd just use a tent and a very warm sleeping back and about 20 layers of clothes...

Anyone winter tent/igloo camp before?

I do support for a 48 hour orienteering race in January. That means about 72 hours camping at a check point. It is a lot of fun. I suggest a cot to get off the ground. Three of us shared a tarp tent where we cooked, slept, and ran our radio communications center. It was quite warm with a single propane heater. There was another group which had a better tarp tent which we have now copied. We used it once this summer and it was very easy to set up.

Here is their version...

[SpartyOn]

Want to try winter camping this year...maybe 2 or 3 days...try to do it with temps that aren't outrageously cold (maybe 20Fs)... I'm watching "Survivorman" (its back) and he's in Norway (winter) and it just looks like it would be fun (if you are properly prepared...lots of food!). I'd just use a tent and a very warm sleeping back and about 20 layers of clothes...

Anyone winter tent/igloo camp before?

Yes... Backpacking style though. Light weight and warm and miles deep with not a road in sight (the best)

Its all about your gear. Don't cheap out! Staying warm is your # 1 goal and it isn't easy when you are sleeping on the ground in 20f or colder weather. Synthetic fabrics and gortex are your friend. Use a small tent to lock your heat in. Place your tent under a tall stand of trees to avoid wind. Also make sure you understand sleep sacks and how they work with respect to the temps. If your miles in the woods, a cold night hurts. Stay warm and have fun.

[Entropy]

My initial winter outlook

Winter Outlook, 2012-13. Expect very mild weather overall, but more snow & cold late.

I’ve been doing some research on the various teleconnections and how they are shaping up for this winter. Based on my research, it appears a very mild winter is likely to occur during 2012-13.

Introduction:

The following indices were researched: the El Nino Southern Oscillation (ENSO), Pacific North-American Index (PNA), East-Pacific Oscillation (EPO), Arctic Oscillation (AO), North Atlantic Oscillation (NAO), Pacific Decadal Oscillation (PDO), Atlantic Multi-decadal Oscillation (AMO), analogs, climatic trends with respect to temperature and precipitation, recent pattern progression/repetition, autumn precipitation/temperature departures, sea surface temperature anomalies in both the Atlantic and Pacific, cryospheric evolution (trends, anomalies), and solar trends.

The following factors are what I put the greatest amount of focus on in making this winter forecast:

- Northern Hemispheric trends

- The Pacific pattern (ENSO, EPO, PDO/PNA, NOI/SOI*, etc..)

- The Northern Atlantic pattern (NAO)

NORTHERN HEMISPHERIC TRENDS

As many of you know, we are in the middle of one of the warmest years on record in the Northern Hemisphere. The much warmer than average temperatures over the past decade has significantly affected SSTs, as well as temperatures across the world. Below is a map of the mean global temperature from 1999-2008 vs the 1940-1980 averages.

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Here is a graph of the earth’s temperature trends over the past 60 years…

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As you can see by these images, the earth is much warmer today than in previous decades. Regardless of what you feel is the cause of the trend, the point remains that the earth’s temperature (especially in the Northern Hemisphere) has been rising rapidly since the 1970s. When making a long range forecast, you cannot ignore this long-term trend.

The main reason for me bringing this up is that North America and the US are affected by this the most in the winter months as the earth’s tilt is the farthest away from the sun, making temperatures more extreme. Over the past 10-20 years, there has been a marked trend towards warmer than average winters, especially across the Upper Midwest. Here is a map of the past 10 winters (DJFM) across the US versus the 1950-1995 long-term average. Note that the scale on this map is +/- 4 degrees.

Now that we have looked at temperature trends of the past 10 years/winters, let’s take a closer look at the past year across the US to see if we are showing any signs of a pattern break.

Since the first of this year, 2012 is currently ranked number #1 warmest out of every year since 1895 for temperature to date. Here is the NCDC rank of top 10 warmest Jan-Aug periods in the past 118 years:

Already in 2012, we have set the following monthly records (based on 118 years of data):

- January 2012 was the 4th warmest on record.

- March 2012 was the 1st warmest on record.

- April 2012 was the 3rd warmest on record.

- May 2012 was the 2nd warmest on record.

- July 2012 was the 1st warmest on record.

As far as seasons go, we are on quite a streak as well (this is also based on 118 years of data):

- Summer 2011 (JJA) was the 1st warmest Summer on record.

- Fall 2011 (SON) was the 16th warmest Fall on record.

- Winter 11-12 (DJF) was the 4th warmest Winter on record.

- Spring 2012 (MAM) was the 1st warmest Spring on record.

- Summer 2012 (JJA) will also be among the warmest on record.

What all this says is that the warm trend is not only far from breaking, but is now stronger than it ever was.

In conclusion, what the trends show is that it is harder now to get an entire winter average out to be cooler, than it was a few decades ago. However, we can still get very cold winters throughout much of the country in this pattern, as occurred during 2009-10 & 2010-11, if certain global factors set up right. Overall, the trends are a very small piece to the overall puzzle, but are worth mentioning.

THE PACIFIC PATTERN

ENSO (El Niño-Southern Oscillation)

It is still looking like this El Nino will peak in the low-end Moderate range. If my thinking is correct, Nino 3.4 SSTs will go over +1.1 sometime before the end of this year. The model consensus is slightly less than this, peaking around +1.0C during the OND period.

The reason I believe a somewhat stronger, although early peaking event is likely, is from research conducted by StormchaserChuck several years back. He found the earth undergoes through a major change sometime in the Spring between March and May. At this time, future ENSO and NAO trends are given for the rest of the year, and once the wheel starts turning, it is very hard to stop it. The big signal to a coming Mod-Strong Nino or Nina (1st is subsurface temps) is given by springtime MEI values. Where the Mar-Apr MEI value is fairly neutral (i.e. below 1 and above -1), and this is followed by an increase in Apr-May by greater than 0.4C, the odds tip strongly in favor of a Mod. to Strong El Nino. In 2012:

The Mar-Apr MEI number was 0.059

The Apr-May MEI number was 0.706

This means that the change between these months was +0.65.

There were only 8 years where the we saw a weak Mar-Apr MEI (nothing over or under 1.0) that rose greater than +0.4 between Mar-Apr and Apr-May with the Apr-May MEI also being weak (nothing over or under 1.0). These 8 years were:

1957

1965

1972

1982

1986

1997

2002

2006

Every one of these years (100%) saw a CPC defined El Nino by the end of the year (is happening right now).

Every one of these years (100%) saw a MEI of greater than +0.5 by Jul-Aug (happened this year).

Every one of these years (100%) saw the MEI reach +1.0 before the end of the year (happened this year).

Every one of these years (100%) saw a Nino 3.4 max that was at or greater than +1.5 sometime before it died down. (not there yet)

Here are the maxes for my individual analog years (based on 1971-2000 climatology).

The 57-58 Nino maxed out at +1.6 making it a STRONG Nino

The 65-66 Nino maxed out at +1.6 making it a STRONG Nino

The 72-73 Nino maxed out at +2.1 making it a STRONG Nino and the 3rd biggest on record

The 82-83 Nino maxed out at +2.3 making it a STRONG Nino and the 2nd biggest on record

The 86-87 Nino maxed out at +1.6 making it a STRONG Nino

The 97-98 Nino maxed out at +2.5 making it a STRONG Nino and the largest on record

The 02-03 Nino maxed out at +1.5 making it a MODERATE Nino

The 06-07 Nino maxed out at +1.1 making it a low-end MODERATE Nino

Above is data solely from the Spring. To get a better idea as to where we are heading, here is what recent data is showing as far as the progression of this El Nino goes…

The September OHC (Ocean heat anomalies) are now warmer than they have ever been this year, as our warm pool below surface has gained a lot of strength over the past few weeks. Below is a loop of the subsurface temperature anomalies of the past 2 months, which shows how OHC is progressing.

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As of August 29, Nino 3.4 was measured at +0.9C, and is rising. We have now risen +2.1C since early February, and +0.4C since the beginning of July. Since 1950, there have been 7 times where the Sept ONI was < +0.8 that went on to see an ONI max of +1.0 or greater in the winter —

1957 – Sept ONI (+0.8)

1963 – Sept ONI (+0.8)

1968 – Sept ONI (+0.2)

1986 – Sept ONI (+0.7)

1991 – Sept ONI (+0.8)

1994 – Sept ONI (+0.7)

2006 – Sept ONI (+0.6)

1957 – ONI max +1.6 (January)

1963 – ONI max +1.0 (Nov-Dec)

1968 – ONI max +1.0 (Jan-Feb)

1986 – ONI max +1.3 (January)

1991 – ONI max +1.8 (January)

1994 – ONI max +1.3 (December)

2006 – ONI max +1.1 (Nov-Dec)

Going by Nino 3.4 data (i.e. the ONI), it is safe to say that a Moderate or even borderline Strong El Nino peak is still not out of the question (although a Strong max is far from likely) climatologically speaking. I currently favor a low-end Moderate event, however.

Subsurface ENSO anomalies (or OHC) usually give a good indication as to when the El Nino or La Nina will peak. Climatology says that the peak in surface temperatures usually comes 1-2 months after the OHC has maxed out. With that being said, if you compare the location of where the warm pool below the surface currently is to where it was in past years, it is safe to say that the OHC will max out in October of this year. Given that, and how the ONI has progressed throughout the year, my call would be for Nino 3.4 temperatures to peak at the beginning of December, then decline through the winter. I expect the peak to be between +1.2C and +1.4C making this a Moderate El Nino by definition.

The decline throughout the winter should not be rapid, as there is no real cold water below the surface to enforce the drop like there were in other years. Based on the max, and expected decline rate… Dec, Jan, and maybe the beginning of Feb should have Nino 3.4 SSTs >+1.0 (Mod-Nino state), with late Feb, and March dropping down to a weak-Nino. Given the 1-2 month lag between the SSTs and its effects on our pattern, I will classify this winter as being a Moderate El Nino.

Since I dont believe that only SST numbers show all the effects of ENSO, I am going to use the MEI for potential winter ENSO analogs. The MEI is a measure of all areas of ENSO. This includes, the SOI, OLR, SSTs, etc… Since April, the MEI has been consistantly running higher than Nino 3.4 SSTs. This is one of those years where the SSTs are weakest part of the Nino present. Based on how the MEI has been progressing compared to SSTs, here are my favorite winter MEI analogs:

1957-1958

1965-1966

1994-1995

2006-2007

To illustrate the likely effects of a MEI winter similar to this one, here is a composite temperature anomaly map for the years given above:

PDO (Pacific Decadal Oscillation)

With that said, I thought it prudent to look elsewhere in the Pacific to get a better idea of how things are likely to progress this winter. In poring over the data on PDO, I noticed a strong correlation between August PDO values and the ensuing mean DJFM PDO modality.

All El Nino years since 1950 and their corresponding August & DJFM PDO modalities are given below. I’ve highlighted all years with a -PDO modality in August, and their ensuing winter PDO modality.

1951-52: August – negative, DJFM – negative

1957-58: August – positive, DJFM – positive

1963-64: August – negative, DJFM – negative

1965-66: August – negative, DJFM – negative

1968-69: August – negative, DJFM – negative

1969-70: August – positive, DJFM – positive

1972-73: August – positive, DJFM – negative

1976-77: August – positive, DJFM – positive

1977-78: August – negative, DJFM – positive

1982-83: August – positive, DJFM – positive

1986-87: August – positive, DJFM – positive

1987-88: August – positive, DJFM – positive

1991-92: August – positive, DJFM – positive

1994-95: August – negative, DJFM – negative

1997-98: August – positive, DJFM – positive

2002-03: August – positive, DJFM – positive

2004-05: August – negative, DJFM – positive

2006-07: August – negative, DJFM – negative

2009-10: August – positive, DJFM – positive

16/19 years, or 84% featured a positive correlation between October and the ensuing winter, DJFM. There were eight years with a negative PDO in August, six of them were followed by -PDO winters. The two exceptions were 1977 and 2004, which both had a positive DJFM PDO that was preceded by negative values in October. I feel this is unlikely in 2012, given the overall -PDO regime we have been in recently and no evidence of warming SSTs off coastal California.

Note, too, that of the four closest MEI analogs (1957-58, 1965-66, 1994-95, and 2006-07), three of them occurred during a -PDO, despite the fact that El Nino events are rarer during -PDO modalities (only eight of the 19 cases above occurred during a -PDO). As you can see on the graphic below, the warm pool south of Alaska and the cooler anomalies along the California coastline are traditionally associated with a -PDO regime. Note also the developing El Nino visible on the SST anomaly map below.

PNA (Pacific/North American Pattern Index)

The correlation between the PDO (which is more of a SST index), and the PNA (which is a pattern index) is greater than 0.80 in the winter months. Given the expectation of a -PDO winter, it might be reasonable to expect a correspondingly negative PNA. Somewhat surprisingly, however, the correlation disappears in -PDO, El Nino winters. Only three of the eight cases had a -PNA. Those were 1951-52, 1965-66, and 1968-69. In all remaining years, the mean DJFM PNA was positive. Since PNA and EPO are inversely correlated, this arrangement would favor a -EPO, which tends to favor enhanced blocking in West Canada and Alaska.

Unfortunately, StormchaserChuck has shown that the impact of -EPO is minimal during El Nino winters. This was evident during the winters of 1991-92 and 1994-95 and, to a lesser extent, 2006-07. During these winters, the EPO was quite negative, but the Pacific flow across the northern US and Canada simply overpowered the -EPO effects. Because of this, it is probable that the EPO will not be a significant factor during this winter.

CONCLUSION

Expect the following indices this winter in the Pacific:

- Moderate El Nino, weakening throughout the winter

- Negative PDO, but positive PNA

- Somewhat negative EPO, but having minimal impact

The best analogs for the upcoming winter, based on the state of the Pacific include:

1957-58

1965-66

1986-87

1994-95 (personal favorite)

2004-05

2006-07

The composite temperature anomaly map for these six winters is given below:

http://www.esrl.noaa....20.13.prcp.png

THE ATLANTIC PATTERN

NAO (North Atlantic Oscillation Index)

Aside from extreme ENSO events such as 1982-83 and 1997-98, the NAO is probably the most important long term factor that determines how the pattern sets up across North America and Europe. StormchaserChuck described a novel approach for predicting the NAO state up to six months in advance with reasonable accuracy.

First, some background, the NAO is a pressure index that lies roughly between Iceland and the Azores. A lower pressure in Iceland with a higher pressure over the Azores would result in a +NAO. A higher pressure in Iceland with a lower pressure over the Azores would result in a -NAO. Sea temperatures both on the surface, and below the surface have a big effect on pressure changes in these regions. For more on the relationship between subsurface temperatures and pressure indices, see this thread:

http://www.easternus...?sh…=103685&hl=.

In a nutshell, Chuck’s method involved dividing the Northwest Atlantic, from the Davis Strait south to near 35N, into two regions. Below is a map of the Gulf stream and North Atlantic steering currents. The red dot on the map is approximately where the Azores are. The blue dot on the map is where Iceland lies. Around these two areas are where the NAO is measured. The black circled area is one of the areas Chuck’s research focused on. Chuck called this region “Area B.”

http://img398.images...untitledtj1.png

The 2nd area that Chuck focused on is the dark blue circled region just south of Greenland, which he referred to as “Area A.”

http://img247.images...7/7373/1vs4.jpg

As shown in the images above, the currents that lead to the Azores ultimitely come from the North and West, and are originally located south of New Foundland (the black circle in the 1st map). The currents that lead to Iceland come from all directions, but mostly west of where the island is. This is very important to note since subsurface temperatures play a major impact on pressure indexes, and subsurface temperatures travel with the ocean currents.

Chuck uncovered two times of the year where SSTs are most excited in that their subsurface temperatures will emerge — the Summer solstice, and the Winter solstice. In between these seasons (Summer and Winter), Chuck posited that the warm or cold SSTs tend to plunge below the surface as the Earth’s pattern changes, comparing it to the seasonal progression of subsurface temps in the ENSO regions. This mechanism explains why we usually know if a Nino/Nina will be moderate or strong by the Summer, and also the reason why ENSO events usually reach their peak around Dec 21st.

With that being said, Chuck theorized that one could use May-August SSTs (i.e. centered around the Summer solstice) in certain areas of the globe to accurately predict where warm or cold subsurface temperatures will travel to in a given time (depending upon how strong the current is). He did just this with the NAO.

To get an idea as to what state the pressure indexes near Iceland and the Azores will be in the winter, Chuck broke down May-Aug SSTs across areas A and B in the maps below to get an anomaly.

http://img156.images...488/naoavb2.png

To get a very accurate reading, Chuck took every year since 1949, magnified the map, and broke it down block by block, like what is shown below for 2006. He added the boxes up, and divided them by however many blocks there were to get an even number for the entire area. This was based on the anomalies from 35N to 70N as well as 70W to 30W, with everything north of 52N being counted as area A, and everything south of 52N being area B.

http://img168.images.../4953/06iz8.png

Since the total of Area A came out to be higher than Area B, Chuck multiplied the reading from area B by 1.51 to make it even. To get a total anomaly from the two regions, Chuck subtracted the number he received from Area A from the number he got from Area B. The total data of Area A, Area B, and the total of the two regions for every year from 1949 to 2005 can be found at the link below:

http://www.easternus...?sh…c=56818&hl=

Using this method alone, the Standard Deviation came out to be 0.47

Looking closer into the years that had the most error, Chuck discovered that the ENSO state can throw this formula through some loops. In the 6 strong ENSO winters since 1950, where the MEI averaged out to be above +1.5 (strong Nino) or below -1.5 (strong Nina), the average deviation was off by +0.66. Seeing how the ENSO state plays a strong role on the entire Global pattern, he added a +0.50 anomaly to the years that were and are expected to be a Strong Nino or Nina.

In the 12 Moderate ENSO winters since 1950, where the MEI averaged out to be between +1.0 and +1.5 or between -1.0 and -1.5 for the winter, the average deviation was off by +0.24. Since Moderate ENSO events can impact the NAO, but not to the extent of a strong ENSO event, he added +0.20 to every winter that was a Moderate Nino or Nina.

There was no strong error rate one way or another with ENSO neutral or weak ENSO winters, so Chuck left these unadjusted. Including ENSO into the formula brought the average deviation down from 0.47 to 0.42.

Here are two charts showing the correlation between the predicted and actual NAO states using Chuck’s formula:

http://img100.images...0/3228/1hc1.png

http://img222.images...2/8132/4na1.png

With that background out of the way, it’s time to look at where SST anomalies were this summer for the relevant region.

http://www.esrl.noaa....anom.month.gif

We can see that most of the NW Atlantic is running well above normal. However, the warmest anomalies seem to be located in the vicinity of Area B along and south of PEI. This would favor a +NAO, especially when the 1.51 multiplier correction factor is applied to Area B. In addition, the expected Moderate El Nino would somewhat amplify this effect. I am not going to count pixels as Chuck did, but there does seem to be support for a positive NAO on this basis.

It’s worth noting another strong correlation involves October NAO state. It has been noted that the winter (DJFM) mean is often the opposite of the October monthly NAO. In other words, a strongly negative or positive NAO in October is typically followed by the opposite during the winter. Obviously, it is not yet October but we should have more information once we get to that point. In addition, above normal October snow cover in Siberia is thought to favor a negative NAO during the winter, according to research by Dr. Judah Cohen. Currently, snow cover has been running below normal, but we could see rapid increases over the coming month or so.

Finally, it was also pointed out to me that, during El Nino years, the NAO index is frequently the same sign of the QBO index.

http://forums.accuwe...16472_thumb.jpg

http://forums.accuwe...16877_thumb.jpg

Currently, the QBO is near -28, which would favor a -NAO. However, this QBO reading is on the tail end of the its biennial falling cycle. The QBO has now peaked and will be beginning its rise towards a maximum value sometime next year. In fact, the year closest to this one is none other than — 1994! Yes, during 1994, the negative-QBO cycle peaked in July and August right around -28, which is close to where we currently reside. However, the QBO index rapidly rose over the fall, reaching above zero by December! The QBO remained positive throughout the winter of 1994-95 and the NAO was, as predicted by this correlation, highly positive. The complete QBO data is available here: http://www.esrl.noaa...lation/qbo.data. Note the striking similarity in this year’s QBO and that present in 1994. There have been other years with a similar pattern, but none featured an El Nino, like that expected this winter and that occurred during the Winter of 1994-95.

In light of the QBO signal and the current observed SSTs in the NW Atlantic, it appears that a positive NAO should be the favored state this winter. That is not to say that periods of -NAO cannot occur, but that they will be the exception rather than the rule.

AO (Arctic Oscillation)

With respect to the AO, El Nino years overwhelmingly tend to feature a -AO. But the AO is closely related to the NAO (correlation ~0.85 during the winter). In the years that featured a predominantly +NAO, a +AO was also favored. This was the case in both 1994-95 and 2006-07, which have consistently appeared as the closest analogs to the current year.

It’s worth noting, also, that Arctic sea ice is at unprecedentedly low levels as shown in the graphic below.

http://neven1.typepa...448b5287970d-pi

It’s not yet known what effects this may have on winter conditions, but I suspect it favors a +AO. There is some anecdotal evidence that low sea ice leads to more and stronger Arctic cyclones. Deep low pressure over the Arctic favors a -NAO and -AO, as I already explained how those indices operate. In August, we observed a record-breaking 963mb low over the Arctic Ocean and currently a 988mb low is affecting the same region. Whether this trend continues is not yet knowable, but it does lend some support to the idea. I should add that this is one proposed mechanism to explain the warm, wet winters characteristic of the mid-Pliocene in the middle Latitudes and may become a more permanent fixture in coming years.

Conclusion

Based on the information mentioned above, I am using the following to make a forecast for the winter:

• Warm seasonal trends.
  
• Low-end Moderate El Nino, peaking early.
  
• NAO, averaged greater than +0.5.
  
• PNA, averaged greater than +0.5 (with a negative PDO).
  
• EPO, averaging somewhat negative to neutral, but having minimal impact.
  

The following analogs appear as the best fits: 1986-87, 1994-95 and 2006-07. Of these years, I prefer 1994-95, followed by 2006-07. For the composite analog map below, I triple weighted 1994-95 and double-weighted 2006-07.

I plan on producing some maps of my own, as well as going into greater detail about how I foresee the winter. Basically, however I suspect it will be mild overall with less than normal snowfall. The best chances of snow & cold will be from late January and on, with the first half of winter likely featuring unusual warmth.

• 
  

[SpartyOn]

Excellent write up!!!!

[toronto blizzard]

Great another warm snowless winter. FML. Torcharties favourite

[Snowstorms]

Great another warm snowless winter. FML. Torcharties favourite

yeah, sadly. I want to move out of southern Ontario -_- The last true legit winter was 2008-09 and that was 3 Winters ago.

The GOA was trending towards a slightly better solution but back offed. Even though the MEI suggest a Weak Nino anomaly, global patterns aint in a El nino pattern yet with GLAAM remaining negative.

Oh well, lets see. Still September only, lawls.

[michsnowfreak]

Great another warm snowless winter. FML. Torcharties favourite

lol dont fear yet. Unlike the previous two winters, when outlooks were fairly unanimous (2010-11 spot on, 2011-12 dead wrong), Ive seen outlooks across the board so far for 2012-13. If you want to use the unscientific version, the Farmers almanac is predicting a cold, snowy winter in the Great Lakes. (They were wrong last year, and admitted as much, but pretty much spot on for the previous many years....so lets hoping they are back on track). http://www.freep.com...D=2012308290056 . Also, cant wait for Deedlers outlook, and the few hints he dropped in his Autumn outlook I am liking already.

Though Entropy certainly used a lot of data, and Im not saying he cant be correct, let me state a few of the questions I have on that outlook.

First, while enso is clearly just ONE factor that goes into forecasting a winter, of the 8 analog years at the beginning of the post, 6 were strong Ninos and 2 moderate....whereas this 2012-13 has been forecast pretty much across the board as weak to at most moderate. (though in the end the favorite analog of that outlook was 1994-95, which was not a strong/mod nino).

My 2nd factor is using trends of winters of the past 10 years. Just hearing that statement I jump for joy as heavy snow has been the rule the past 10 years (like most winter-lovers, snow is certainly higher on my list than temp anamoly). But I was looking at that map and thinking, WOW has it really been THAT mild the past 10 years? Then a few things jumped out on me. Winter temp is DJF, not DJFM. Using March when we just finished the warmest March on record (and had another extremely mild one in 2010) will instantly skew that data. Also, 2001-02 to 2011-12 is not 10 years, thats 11 years, so to do a 10 year average, one of those 2 extremely mild years must be chopped off.

While the upper midwest has clearly been running mild no matter how you look at it, much of the rest of the country looks quite different based on what data set is used.

The past 10 years winter average looks like this, DJF 2002-03 thru 2011-12 with the 1950-1995 avg

Since 1971-2000 normals were used for enso climatology normals in entropys outlook, we should stay consistent and use 1971-2000 normals for temp anamoly the past 10 years. DJF 2002-03 thru 2011-12 per 1971-2000 normals

If you want to look at the last 10 years in comparison to the most recent normals (1981-2010) then you have a much bluer look (though granted, this is 1/3 of the normal period as it is...though it does show that the last 10 years were somewhat cooler in many regions than the previous 20).

******************************************************************************************************

When you go back 30 years, clearly the 10 winters just passed were colder than the previous 20 when using the longterm 1895-2000 normals.

2002-03 thru 2011-12

1992-93 thru 2001-02

1982-83 thru 1991-92

I am not trying to criticize the above outlook, I didnt even touch any of the MEI, PDO, NAO, etc talk because frankly I do not know enough about those things. I merely am pointing out my issues with the warming trend of winters of the past 10 years being false.

[Trent]

I am not trying to criticize the above outlook, I didnt even touch any of the MEI, PDO, NAO, etc talk because frankly I do not know enough about those things. I merely am pointing out my issues with the warming trend of winters of the past 10 years being false.

The one difference is whether or not you include March or not as part of winter, as the O/P did. If you include March, the past 10 years have been not much different compared to the long term scale.

I think that might shed some light to the theory of recent and future winters being concentrated into short, but intense cold periods, with abnormally warm shoulder months that create an overall average of warmer cold month seasons.

For the most part, tossing in March shows a warming trend.

If you toss in November and March, the past 10 years have been much warmer:

[michsnowfreak]

The one difference is whether or not you include March or not as part of winter, as the O/P did. If you include March, the past 10 years have been not much different compared to the long term scale.

I think that might shed some light to the theory of recent and future winters being concentrated into short, but intense cold periods, with abnormally warm shoulder months that create an overall average of warmer cold month seasons.

For the most part, tossing in March shows a warming trend.

If you toss in November and March, the past 10 years have been much warmer:

First Id like to say, stupid me for generating all those maps in my post above and LINKING them (as they obviously expired) rather than attaching them lol.

And absolutely, November & March, BY FAR, are the 2 months out of the 12 that have shown a marked increase in temperature the past decade or so. Its just that when you include both 2001-02 and 2011-12 for a 10 year period (that is really 11 years), both being notoriously mild winters, and add March (again, we just completed the warmest March on record) even though winter temperature is always calculated DJF not DJFM, and lastly...use the data-set of 1950-1995 to show the temp anomaly but then use the 1971-2000 dataset for Nino anomalies, it adds a bit of inconsistency and certainly puts a mild skew on things.

My basic point was with those climate division composites, you have SO many options that you can sort of make a map with VERY different looks depending what data-set you use. My personal fav, simply for its longevity, is 1895-2000. You can choose normal sets of 1950-1995, 1961-1990, 1971-2000, 1981-2010, 1895-2000, or 1950-2007.

For instance, if I take the 9 winters from 2002-03 through 2010-11, doing the exact opposite of the above outlook (omitting both 2001-02 and 2011-12), you have a MUCH different look of winters of the past decade. Even with the longest-term dataset of normals, 1895-2000, you get a cool look outside the upper midwest, but you use the 1981-2010 normals, and its a very blue map.

Basically winters of the past decade (DJF) were overall COLDER than those of the previous TWO DECADES....BUT....also shorter (see Nov & Mar), at least from a temp perspective (several areas saw record early snow (Oct 12, 2006) & record late snow (May 20, 2002) the past decade of winters that had a later start and earlier finish to the cold, ohhh the irony of weather)

***********************************************************************

I redid a few of the maps from my previous post....here is a look at the past 30 years, in 10 year increments, compared to 1895-2000 normals. The 10 years just past were cooler than the previous 2 decades DJF.

2002-03 thru 2011-12

1992-93 thru 2001-02

1982-83 thru 1991-92

[Justin]

Its very easy to manipulate the temp data set to show what you want by tweaking what you show. The previous few posts I think clearly show that, depending on which data is shown gives you a very different look at past Winters.

When I pour over all the data out there now and look at the trend of where things are headed my gut says Winter can't be any worse really than this past one we just came out of.... but I wouldn't be totally surprised to see another fairly mild Winter overall- the thing is I can recall some great weak El Nino Winters that were mild and produced tons of snow. More active sub tropical jet stream that is prevalent in El Nino tends to give systems a good moisture feed and thus the opportunity to really snow. So I'll just say right now the Eastern Midwest and Ohio Valley has a good snow season this year. Just a hunch at this point.

[michsnowfreak]

Its very easy to manipulate the temp data set to show what you want by tweaking what you show. The previous few posts I think clearly show that, depending on which data is shown gives you a very different look at past Winters.

When I pour over all the data out there now and look at the trend of where things are headed my gut says Winter can't be any worse really than this past one we just came out of.... but I wouldn't be totally surprised to see another fairly mild Winter overall- the thing is I can recall some great weak El Nino Winters that were mild and produced tons of snow. More active sub tropical jet stream that is prevalent in El Nino tends to give systems a good moisture feed and thus the opportunity to really snow. So I'll just say right now the Eastern Midwest and Ohio Valley has a good snow season this year. Just a hunch at this point.

Yes...for us north of I-80 mild winter can still be excellent for heavy snowfall. On the other hand, some cold winters can be horrendous snow seasons (may have a solid snowcover though).

Was talking with Harry on his board, and Euro monthlies updated again. VERY little above normal showing up for the whole country and the little bit it has is out west. Basically near to slightly below normal temps from November 1st till April 1st. Yes it now includes March. Coldest departures are along the northern border. 500mb maps show a nice ridge in the pacific up into AK especially in March.

Also a few older but very interesting tidbits I just learned....1880-81 was a weak El Nino! That is possibly the severest winter this region has ever seen. Very few stations had accurate data back then, but two that did (Detroit - 93.6" snow, Lansing - 97" snow) still have that winter stand as the snowiest on record. Also Laura Ingalls Wilders famous book "The Long Winter" describes how blizzards literally buried them in the Dakota prairie that winter.

1881-82 and 1889-90 were both La Nina winters, and were, in Detroit at least, much less wintry and FAR worse for snow-lovers than 2011-12, believe it or not.

[SpartyOn]

Anything will be better than last winter season. It's inevitable, but who knows for that matter. IMO the euro monthlies are useless. Trusting the weeklies is different story.

[Stebo]

Its very easy to manipulate the temp data set to show what you want by tweaking what you show. The previous few posts I think clearly show that, depending on which data is shown gives you a very different look at past Winters.

When I pour over all the data out there now and look at the trend of where things are headed my gut says Winter can't be any worse really than this past one we just came out of.... but I wouldn't be totally surprised to see another fairly mild Winter overall- the thing is I can recall some great weak El Nino Winters that were mild and produced tons of snow. More active sub tropical jet stream that is prevalent in El Nino tends to give systems a good moisture feed and thus the opportunity to really snow. So I'll just say right now the Eastern Midwest and Ohio Valley has a good snow season this year. Just a hunch at this point.

I would agree with this post 100%. A predominant storm track through Eastern Ohio or Western PA/NY could very well occur this year with storms coming out of the Southwest. Of course there would be a secondary typical clipper path out of the Northwest as well.

The key however is I don't expect this winter to be anywhere like last winter with the lack of snow and abundant warmth.

[KokomoWX]

JB's son is trying his hand at long range forecasting. I guess he cannot be worse than dad.

http://firsthandweather.com/blog/all-posts/firsthand-weathers-20122013-preliminary-winter-forecast

[hm8]

JB's son is trying his hand at long range forecasting. I guess he cannot be worse than dad.

http://firsthandweat...winter-forecast

I swear if I see the phrase "winter battle zone" one more time imma explode

[A-L-E-K]

I swear if I see the phrase "winter battle zone" one more time imma explode

+1

[Jonger]

It seems these patterns and attempts at seeking analogs rarely hold up. Btw, the past 12 years December's have averaged right at normal overall... So warm falls havent seemed to affect winter.

Sent from my ADR6425LVW 2