Normally, I would present the full set of weather data, but due to a change in publishing frequency, we’ll return to a more general summary format.

Warm in Manitoba

October continued the pattern of well above-average temperatures that began in September. Across Alberta, mean monthly readings were about 1.0 C warmer than normal, increasing to roughly 2.0 C above average in Saskatchewan.

Manitoba was the warmest of the three provinces, with mean temperatures running 3.0 C to 4.0 C above normal. Winnipeg recorded the highest mean temperature at 8.7 C which was 3.7 C warmer than average, while Peace River was the coolest location, reporting a mean of 4.1 C, still 1.3 C above normal.

Fall rain builds water reserves

Precipitation told a different story. October was wetter than average across the southeastern and northern Prairies, with southern and eastern Manitoba seeing the greatest totals. These wetter conditions stretched northwestward through north-central Saskatchewan and into northeastern Alberta.

Winnipeg stood out as one of the wettest spots, recording 93.7 mm of precipitation, which was nearly 60 mm above the long-term average. North of Winnipeg, I measured over 135 mm at my own location, which made the month feel more like spring runoff than autumn rainfall, with ditches running full and pumps working overtime.

Further west and south, conditions dried out considerably. Regina reported just 28 mm for the month, while precipitation amounts dropped to near zero across parts of southwestern Saskatchewan and southern Alberta. The sharp contrast in rainfall across the Prairies highlights the uneven moisture patterns that continue to shape soil and field conditions heading into winter.

Winter forecast 2025

OK, now back to our winter weather outlook and the factors that may be controlling our winter weather. The early snowfall in Siberia and its influence on the Arctic Oscillation or North Atlantic Oscillation tends to lead to warmer- and drier-than-average winters across the western Prairies, with eastern regions seeing average to below average temperatures along with average to above average precipitation.

The same holds true for a warmer than average northern Pacific: warm dry west, cool wet east. So, if this was all we had to factor in, then I would say there is a pretty good chance this is what we would see this winter.

But there is a third, and in reality, a fourth player. The third player is La Niña, and while it is forecasted to be fairly weak, La Niña conditions often result in a colder-than-average winter across the Prairies with wetter-than-average conditions over western regions with near- to below-average precipitation over eastern regions. This goes against what the other two are calling for.

The last player is random chance and unexpected variations in global weather patterns. Different combinations of events, that on their own leads to a specific outcome, might combine to gives us something new. This is the difficulty in trying to predict long-term weather. While computer modelling has greatly improved forecasts out to 10 or so days, there has not been a huge change in our accuracy in our forecast’s months in advance.

Now let’s look at the different long- range forecasts or predictions and see what they are calling for this winter. Starting off with the almanacs, the Old Farmers’ Almanac is predicting that the winter will see above to well-above average temperatures along with near to slightly above average precipitation. The Canadian Farmers’ Almanac is calling for near- to below-average temperatures this winter and above-average precipitation.

The CFS model, which I find is one of the more accurate, is calling for near-average temperatures this winter with northern and northwestern regions transitioning into below-average temperatures as we work our way into the heart of winter. This model is calling for near-average precipitation across the eastern Prairies and above-average across the west.

Next up is the Canadian CanSIPS model, which is predicting above-average temperatures to start the winter with temperatures transitioning to near average values as we move into December and January. Their precipitation prediction is for a near average start to the winter right across the Prairies with western regions seeing above average amounts during the second half of winter.

The U.S. NOAA’s prediction, extrapolating northwards, appears to be calling for temperatures to start out around average and then transition to below-average. As for precipitation, they are calling for above-average amounts in the west with near- to above-average amounts in the east.

Last on the list of winter weather prediction is the European ECMWF model which is calling for near-average temperatures right through the winter. This is the first time in a long while that this model has departed from predicting above-average temperatures across our region. Their precipitation forecast is similar to most of the other predictions with western regions expected to see above-average amounts with eastern regions seeing near-average values.

If we look to see if there is any kind of consensus, we see a fairly equal split between above-, near-, and below-average temperatures. Precipitation on the other hand is strongly leaning toward near- and above-average amounts.

If I was to go out on a limb, I am leaning toward highly volatile winter temperature-wise with large fluctuations over the winter which will even out to near-average temperatures. As for precipitation, I have to go with the majority and say above-average precipitation with possibly the southern half of Alberta seeing near-average amounts.

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So far, the heart of the arctic highs that have been pushing southeastward out of the Yukon and Alaska have stayed to our west. This pattern looks to continue during the first half of this forecast period as another arctic high slides down through Alberta and southern Saskatchewan and then into Montana, before tracking eastward across South Dakota. This high will keep our skies clear to partly cloudy and temperatures will remain at or below the usual temperature range for this time of the year.

By the weekend, the weather models show a very large and strong storm system developing over Colorado and then tracking northeastward towards the Great Lakes. With strong high pressure pushing southward out of Alberta, it looks like this system will stay well to our south, with only some clouds and maybe a few flurries making their way into extreme southern regions late Friday or Saturday. As usual, we will need to watch this system just to be safe, but odds are very low that it will move far enough north to affect us significantly.

Behind this system, more arctic air will build in, keeping our temperatures on the cold side over the weekend. By Monday, the arctic high will be well to our southeast, which will place us in a westerly flow. This should help to moderate temperatures back to near- or even above-normal values by Tuesday.

Looking further ahead, the weather models show temperatures staying around average over Christmas, with only a few small chances of seeing some light snow. More on that next week.

Usual temperature range for this period: Highs, -19 to -2 C ; lows, -28 to -11 C.

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The driest areas in India are important pulse-producing regions in northeastern Andhra Pradesh and neighbouring Uttar Pradesh, said Drew Lerner of World Weather Inc.

“That particular region is hurting pretty bad for moisture.”

The region’s vegetative health index suggests the crops are under pressure, and that particular pocket will probably see lower production, Lerner said.

“Nothing’s a write-off,” he said. “But if it continues to be dry and warm, then yields will be much lower.”

The crops’ health can reverse quickly, he said, and production losses can be limited if pulse crops get rain before moving through the reproductive cycle.

India’s pulse crops should be entering the reproductive cycle at the end of the month or slightly later due to later seeding.

Lerner said he expects India will see at least some much-needed rain. “The question is whether it’ll be well-timed, or if it’ll come late; at this point I would still lay fairly high odds that there’s going to be some rain.”

He said he also expects cooler temperatures going into the reproductive season, which will help perk up the crops.

“The thing that hurts crops more than anything else in the world is heat during February. If it’s hot, they’re going to lose a lot of crop.”

One of the biggest factors for India’s recent dry stretch, Lerner said, is the positive phase of the Arctic oscillation — a climate pattern with winds circulating counter-clockwise around the Arctic — which didn’t allow storms into India.

The Arctic oscillation recently turned negative, which has allowed a shift to the south.

“There’s plenty of rain moving through the Middle East, which hasn’t been able to move across India, but I think it’s just a matter of time.”

Reproduction may occur at the end of January in many cases, or slightly after, Lerner said, but heat in October and November may have delayed some seeding, as producers opted not to get into the fields until it cooled down.

“I think there’s going to be a small loss, but I don’t think it’ll be nearly as significant as it will be if they don’t get rain.”

— Jade Markus writes for Commodity News Service Canada, a Winnipeg company specializing in grain and commodity market reporting.

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In the last article we continued our look at the North Atlantic Oscillation (NAO) and the Arctic Oscillation (AO) and tried to picture how these two features can influence our weather. We left off by looking at how, if the NAO is positive, then it would seem that the AO would also be positive, but this is not always the case. If we have a positive NAO, that means both the Icelandic Low and the Azores High are stronger than usual. The AO is said to be positive when the upper low, or Arctic vortex, over the North Pole region is stronger than usual and at the same time the Azores High is stronger than usual.

So, if we have a positive NAO, then the Azores High is stronger than usual, but at the same time the Arctic vortex could be weak, which would result in a negative AO. Now this is when we have to start hurting our brains thinking about all the different combinations that can occur with just these two different circulation patterns and how each of these combinations can affect the weather.

As we have pointed out several times over the last month or so, both the NAO and AO have been very strongly positive for most of the fall and winter. We know that for both of these features, a positive index usually results in warmer weather for our part of the world. Since both were strongly positive, it’s not surprising that we had such a warm winter. Before we go on to why forecasters missed this when they created this winter’s long-range forecast, let’s examine some other combinations that could occur.

Let’s say that the NAO was positive but the AO was negative. One would be pushing our weather toward warmer-than-average conditions while the other would be pushing us toward colder than average. What would the end result be? That’s hard to say. The easy answer would be average weather conditions, and in the long run that might be correct. It’s possible that under these conditions, the weather might oscillate between periods of extreme warmth and cold. Much of it would depend on just how strong one of these features was compared to the other. So far we have been talking as though these features are either strongly positive or negative, but just like everything else that has do with weather, they are in a constant state of flux. That is, the strength of each pattern changes from day to day and week to week. So in reality, there are numerous different combinations of pressures that can occur, each of which can result in different overall weather patterns. It’s only when they stay in one type of pattern for an extended time, and that pattern is stronger than usual, that their influence on our weather becomes — if I dare use the term — predictable.

Controlling factor

It’s the lack of predictability of these two patterns that makes using them for long-term weather forecasting difficult. With our current state of understanding of these circulation patterns, we can at best only forecast changes about two weeks in advance. So while we know they can possibly have a big impact on our weather, we just can’t reliably predict them far enough into the future to be of any use.

This is why forecasters tend to hang their forecasting hats on the atmospheric and oceanic circulation known as El Niño and La Niña. I have written about these features several times over the years and I don’t have time to go into any depth about them this week. The big reason forecasters put so much confidence in these features is the fact that they are a slowly changing circulation pattern we have now gotten pretty good at predicting even several months in advance.

When forecasters were trying to figure out what the long-range forecast was going to be for this winter, the Pacific was experiencing a moderate to strong La Niña and the long-range forecast for this feature showed it remaining in the moderate range for most of the winter and possibly into the spring. Now, as we are starting to enter spring, La Niña is exactly as the models predicted. So it’s understandable that forecasters would use this as their main controlling factor for our winter’s weather. Typically, when there is a moderate to strong La Niña, our part of the world sees colder-than-average conditions along with more snow, and this is what was forecast. What forecasters didn’t count on was the prolonged strong positive phase of both the NAO and AO, which basically overrode the effects of La Niña.

What will be interesting is to see is how the weather will play out over the next month or so. It appears the NAO and AO are now either negative or around neutral and have been in this state for at least the last two to four weeks. The two-week forecast for both of these continues to show them remaining neutral. With La Niña still in place, I wonder if we will finally see some of that cold, snowy weather we were supposed to be seeing all winter long.

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“Less-than-normal precipitation across the Canadian Prairies ahead of the winter freeze-up have already left soil conditions on the drier side,” said Drew Lerner, with World Weather Inc. of Kansas City.

The absence of significant snowfall and above-average temperatures across Western Canada likely means “it’s going to be a tough year” in some regions, he said. The situation is most acute in Manitoba and southeastern Saskatchewan, Lerner said, with Alberta’s Peace River region also on the dry side.

Colder weather is expected by the third week of January or early February, and that transition could generate snowfall, he said. However, Lerner added he is concerned a drop in temperatures could create conditions that force the jet stream down into the U.S., which could perpetuate the dry spell as that could prevent major storm activity that could provide much-needed moisture.

“It all comes down to the Arctic Oscillation pattern,” Lerner said. “I am expecting a negative Arctic Oscillation during the second half of the winter in Western Canada.”

If that doesn’t happen, the Prairies are more likely to see a better mix of weather during the remainder of the winter.

“Producers in Manitoba and southeastern Saskatchewan should probably take a defensive stance in preparing for a dry season and consider crops that are better performers in this kind of environment,” Lerner said.

In west and central regions of Saskatchewan, dry conditions will prevail at seeding time, but good precipitation is anticipated during the summer, he said.

“It’s definitely going to be dicey for the producers at seeding time, but their crops should see a lot of good rain in the heart of the summer,” Lerner said.

If La Nia prevails over the whole of the summer, then the southeast portion of the Prairies was really going to “take it on the chin,” in terms of being dry, he said.

Lerner said it’s normal to have a dry spell after a couple of years of above-average moisture, and conditions are, so far, pointing in that direction.

The lack of snow cover has producers with winter wheat or fall rye fearing a cold snap will cause winterkill damage. Recent grass fires in southern Alberta are also an indication of the dry conditions that currently exist.

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The main weather story so far this winter has been the unusually warm weather we’ve been experiencing, and over the last week or so we’ve seen this warm-weather story hit new highs — literally! All across the Prairies, starting late last week and lasting right through to the beginning of this week, record-high temperatures were reached, broken and, in some cases, shattered.

It would be easy to just list all the records that were broken during this latest warm spell, but that would end up taking up most of this article. Instead, I thought we should take a look at what’s causing all this warm weather and what conditions came together to bring this unprecedented weather to much of central North America.

If you read last week’s article you might remember the part where I briefly described weather pressure patterns known as the Arctic oscillation (AO) and the North Atlantic oscillation (NAO). This is a very well-known interlinked pattern of air pressure across the Atlantic Ocean and has been measured for centuries due to its effects on ocean travel (sailing). In fact, there are fairly accurate measurements dating all the way back to 1845. For those of you who missed last week’s article here is a recap of just what these oscillations are.

Globally, there are regions that tend to be either areas of low or high pressure. The area around Iceland tends to be a region that sees low pressure and we call this low the Icelandic Low. Farther south in the Atlantic, around the Azores Islands, we typically find a large region of high pressure, and this area of high pressure is called the Azores High. The NAO/AO is simply a measure of the pressure differences between the Icelandic Low and the Azores High. If there is a large difference in pressure between the two, the NAO/AO is said to be positive; if the pressure difference is low then the NAO/AO is considered negative.

Since wind speeds are controlled by differences in air pressure, a positive NAO results in strong winds. As the NAO/AO covers a very large area, the impact of these winds impacts a very large area. These strong winds actually help control the strength of the jet stream as it crosses North America. A stronger jet stream tends to keep cold air bottled up north, and allows mild air to flow northward. Also, the configuration of the two pressure patterns allows for stronger southwesterly winds across North America and this also helps to bring warm air northward. So, the positive phase of the NAO/AO usually results in warm winter temperatures across much of central and eastern North America. The opposite phase, or negative phase, of the NAO/AO results in a weak jet stream and weak to non-existent southwesterly winds across North America. In this phase we tend to see cold air having an easy time moving southward, with little northward movement of warm air. This negative phase of the NAO/AO usually results in cold winters across central and eastern North America.

If you remember back to last winter you might recall just how cold and snowy it was across much of the Prairies and eastern North America. Last winter the NAO/AO was in a very negative phase. In fact, it was the most extreme negative phase on record. This year we are seeing the exact opposite. The NAO/AO is in an extreme positive phase and just like last year, it has now officially become the most extreme positive phase of the NAO that has ever been recorded. So it’s not surprising we see record-warm temperatures across a huge part of central North America.

When this year’s winter forecast of cold and snowy weather first came out, that forecast was based on La Nia conditions across the Pacific Ocean. Some of you might be asking, if the NAO/AO can have such a huge impact on our weather, why didn’t forecasters take this into account when they made their forecasts? The reason for this is that while the El Nio/La Nia pressure pattern over the Pacific can be reasonably predicted months in advance, the NAO/AO is much harder to predict, with lead times of only a week or two. What we do know is that the general pattern does tend to stick around for several months, but it can within that time frame, jump quickly back and forth between the two phases. So far this winter it has been mostly positive, whether it will remain mostly positive or become negative is anyone’s guess. If I was a betting man, I would go with more positive than negative, at least for the next month or so, but I’m not a betting man.

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No matter where you were across the Prairies during December, you would have experienced pretty much the same type of weather: warm and dry, at least relative to what we would normally expect December to be like. Every single station I checked reported temperatures well above the long-term average for the month. In Manitoba, both Winnipeg and Brandon reported a mean monthly temperature of -8.3 C, a good 6 C above the long-term average. While it was a very warm month it didn’t even come close to the all-time warmest December on record, which occurred back in 1997, with a mean monthly temperature of -3.7 C. But it was still a very warm month, coming in as the fifth-warmest December on record.

If we thought it was warm across Manitoba, Saskatchewan and Alberta were even warmer. Both Regina and Saskatoon reported a mean monthly temperature of -6.3 C, nearly 8 C above the long-term average. In Alberta, Edmonton reported a mean monthly temperature in December of -5.4 C, while Calgary came in at -1.5 C. Both of those readings were about 6 C above average.

Not only was December very mild, it was also very dry. With the exception of Calgary, all major centres reported fewer than 10 millimetres of water equivalent, with most sites reporting fewer than five. Combine these light amounts of snow with the mild temperatures and you end up with very little snow cover.

Now, if you remember back about a month or so, all the talk was about how cold and snowy this winter was going to be. While there is still a lot of winter left, and we might still see cold, snowy conditions, the big question is, why did we not see the cold and snow during December?

The answer lies with what’s known as the Arctic Oscillation. This is a close relative to the more well-known North Atlantic Oscillation, and it all ties into differences in pressure between a semi-permanent area of low pressure near Iceland and a region of high pressure in the subtropical Atlantic known as the Azores High. When there is a large difference in pressure it is said to be in a positive phase and this usually results in warmer temperatures across central and eastern North America.

This is exactly what we experienced during December. The Arctic Oscillation was in an extremely positive phase, almost the complete opposite of what we saw last winter when it was in an extreme record-breaking negative phase. This allows for warm air to remain in place over our region, keeping the cold air bottled up north. The next big question is, will this pattern remain for the rest of the winter or will it become neutral or even negative, bringing the cold and snow everyone has been promising?

Who called it?

Before we look at that, we have to see who correctly predicted the warm, dry December weather. Looking back, it appears that it was us here at the Co-operator who correctly called for mild and dry conditions. Both the Old Farmer’s Almanac and Canadian Farmers’ Almanac called for either near-average or below-average temperatures and near- or above-average amounts of snowfall. Unfortunately, I realize now that I forgot to include Environment Canada’s predictions for December, so perhaps we would have been tied for an accurate prediction… but I guess we’ll never know. Sorry, EC!

Now, on to January’s weather outlook. According to Environment Canada, the southern parts of the Prairies will see near-average temperatures during the month, while northern regions will see below-average conditions. Both almanacs call for below-average temperatures during January, along with near- to above-average amounts of snow.

Finally, here at the Co-operator, I am calling for near-average temperatures during the month. After a warm start we’ll see the coldest temperatures of the season move in to bring our first really cold snap. This cold snap will last about a week before milder conditions move back in. Along with the cold temperatures moving in, we’ll have a chance of seeing some significant snow as we transition from the mild to cold conditions. Should this happen we’ll also see near- to slightly above-average amounts of snow. If we miss out once again, snowfall will be below average for the month.

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We’ve seen record snowfall and rainfall across eastern North America during December and there has been plenty of cold, snowy-icy weather across large portions of Europe. Farther north, over portions of the Arctic, temperatures have been soaring, with several locations shattering temperature records.

So what’s going on? Well, it seems that the same unusual weather pattern that developed last winter is trying to redevelop again this year. What makes this really unusual is that before last winter, this particular pattern was observed only about four times in the last 150 or so years; we may now be seeing it for the sixth time – but twice in two years.

I guess officially the pattern is being referred to as an extreme negative episode of the North Atlantic Oscillation (NAO). The NAO is a climate pattern over the North Atlantic Ocean and is measured by the difference of air pressure between the Icelandic Low (over the north Atlantic) and the Azores High (farther south in the Atlantic).

The NAO controls the strength and direction of westerly winds and storm tracks across the north Atlantic. If there is a large difference in the pressure between Iceland and the Azores, we call it a positive NAO and this leads to increased westerly winds and mild, wet winters in Europe. Positive NAO conditions also cause the Icelandic Low to draw a stronger southwesterly flow of air over eastern North America, preventing arctic air from plunging southward.

If the difference in air pressure between Iceland and the Azores is small, it is referred to as negative NAO. Under this setup, westerly winds are suppressed and this allows arctic air to spill southwards into eastern North America more readily. Negative NAO winters tend to bring cold winters to Europe and eastern North America, but lead to very warm conditions in the Arctic since all the cold air spilling out of the Arctic gets replaced by warm air flowing poleward.

Under this extreme negative phase of the NAO, warm air flows northward and cold air is forced southward – we have given this weather phenomenon the unofficial title – the upside-down winter or the Hot Arctic, Cold Continents pattern.

One way I heard it being explained was using a refrigerator analogy. The Arctic is the refrigerator creating plenty of cold air. Once in a while someone opens the door to the refrigerator and cold air spills out and the area around the refrigerator cools off. The door is then closed and this area warms back up. Now, when we see an extreme negative NAO develop, it is like the refrigerator door is opened up but someone forgets to shut it. The fridge is still producing cold air, but it is pouring out of the fridge continuously. The fridge starts to get warmer and the area outside the door gets colder and colder.

Looking closer to home we saw what Environment Canada labelled as a truly bizarre weather pattern develop last week. Usually, over the Arctic in the winter, an area of low pressure develops due to all the cold air. This area of low pressure is known as the Arctic vortex (the same Arctic vortex that brought our region the miserable summer weather back in 2004). This year, the Arctic vortex has been replaced by an area of high pressure. This area of high pressure resulted in what is known as a retrograde motion of weather systems across Central and Northern Canada.

During last week, a large storm system over Eastern Canada got caught in the retrograde or “backward” flow and instead of moving out into the Atlantic it moved westward. By the time the weekend rolled around, the low had moved all the way to northern Manitoba bringing snow and mild temperatures. Over southern regions snow showers were the rule, with the showers originating from the North and Northeast as the northern low backed up. At the same time farther north over southern Baffin Island, instead of seeing average temperatures of -21 C for highs, temperatures were above freezing and rain was falling!

What is the cause of this unusual weather pattern? It could simply be one of those things. It is unusual, but it has happened before, and the fact that it has now occurred twice in the same number of years could simply be chance.

A number of atmospheric scientists are not convinced of this and believe that it has to do with the summer sea ice loss. As I have discussed in the past, more open water during summer in the Arctic allows for more or the sun’s energy to be absorbed. That energy is then released during the first part of the winter and all that energy is going to impact the atmosphere. I guess the question is, will the upsidedown winter start to become the winter “norm?”

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Before we start going into some of the details that make our weather so unique, I thought we should examine the big picture of Rossby Waves and how there are general overall patterns as to how they behave. These patterns of behaviour are known as oscillations.

If we look up the term oscillation we find a lot of definitions that state something about a periodic movement around a mean, or a swaying of data around a central point. While these definitions work for what we want to talk about this week, they don’t really hit the weather nail on the head. The best definition I found that really hit the meteorological point is: a single complete execution of a periodically repeated phenomenon, such as the changing of seasons as the sun “oscillates” between the Northern and Southern Hemispheres.

OK, now we have a definition of oscillation that I think we can all work with, now back to the weather. As we have learned, the cold and warm air on our planet is in constant battle with each other; sending globs of itself either northwards or southwards in a slow endless dance that we call Rossby Waves. If you are still uncertain of how these waves work, simply think of a big glob of cold goo sitting on top of the planet. This goo wants to sway southward and the only thing keeping it from doing so is the warm air. Now, picture your hands as the warm air, you can only hold the cold goo from sagging southwards in some locations, and as you do so, more wants to sag southwards in other locations. Now, start to spin the whole thing and you have just a little idea of how complicated the Rossby Waves can get – just a little.

When we look at the different patterns that the Rossby Waves can set up, we end up seeing some general long-term patterns emerge. This does not mean that Rossby Wave patterns are predictable, otherwise weather would be easy to predict. Rather, we find that Rossby Waves tend to go through periods where they favour a particular pattern. This is where we get the term oscillation.

There are four major oscillations that we will examine. Probably the most famous is the El Nińo-Southern Oscillation or ENSO. This is an alternating pattern of high and low pressure across the Pacific Ocean, which then creates differences of ocean and atmospheric temperatures that can greatly influence the weather we experience across much of North and South America. The ENS Oscillation typically lasts between six and 36 months, but can last much longer.

The second oscillation is what is known as the North Atlantic Oscillation or NAO. This oscillation is expressed as a difference between the strength of the Icelandic Low, which is a common Rossby Wave feature, and the strength of the subtropical high to the south (something we talked about earlier this year). When the area of low pressure is weak and the subtropical high pressure is strong, then the NAO is said to be in its positive phase. Under these conditions the northeastern part of North America, along with the Mediterranean, tend to be dry, while northern Europe is wet. This oscillation tends to be unpredictable, lasting for very short periods of time or hanging around for years.

A third oscillation is known as the Arctic Oscillation or AO. As with the NAO, the AO has two phases, warm and cold, and they tend to be associated with the phases of the NAO, especially in winter. When the NAO is in its positive phase, the AO is said to be in its warm phase. Strong high pressure to the south means the Polar Regions will have relatively low pressure. Cold air then tends to get trapped up north and we will have warmer-than-average winters. The main question with these two oscillations is, what triggers them and which oscillation controls the other, or are they mutually independent? So far we just don’t know.

Finally, our last oscillation is the Pacific Decadal Oscillation, or, you guessed it – the PDO. This is one of the longer-lived oscillations lasting up to 30 years (thus the term decadal or decade). This particular pattern is not very well understood, but researchers hope that it will help to better predict ENSO events. But alas, I am running out of acronyms, so I guess it is time to Call It An End or CIAE.

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