That first snowfall last week was a bit early and I am not really sure I’m ready for winter, but then I remember as a snowlover I will be excited for that first major snow storm.

So let’s start looking at the winter forecast…

The Facts

  1. This winter will not be as warm as last winter. Last year we had a strong El Nino which impacted our winter with a very late season, a virtually snowless December (first major storm was after Christmas for Ottawa) and a spike temperatures in late January into February.  This year the pattern will be neutral trending towards a La Nina pattern.  This usually impacts our area with more storms and often colder temperatures.  The ENSO and patterns explained here: https://muchadoaboutclimate.wordpress.com/2013/10/14/enso-explained/
  2. The long models predict a warmer winter. To almost contradict the above fact, the long range models are hanging on to the predictions of a warmer than normal pattern almost globally.  The fact is also that all of the models are warmer, not just one or two.  However the analogs years say otherwise.  What are analogs years?  See below for more info.
  3. The Analogs are colder than the models. All of the analog years being discussed below have some pretty typical Canadian conditions.  They are all years that are colder than what the models are depicting currently.  This provides reason that perhaps the models are too warm and maybe incorrect.
  4. We SHOULD get more snow than last year. This might be saying the obvious, but most areas in Canada had less than normal snowfall last year due to a strong El Nino. Given that we have a different pattern at play this year means we should have more snow this year compared to last.  It will remain to be seen if we get an above average snowfall season.
  5. The Blob in the Pacific COULD have an impact. The blob is an area of warm water in the Pacific coast near Alaska and the BC Coast. The blob has existed for the last couple years and mostly effects weather on the west coast of Canada and the US. However the blob can help develop the Ridiculously Resilient Ridge (RRR) which is an upper atmosphere high pressure that tends to stay put for an extended period and can affect the weather on the coast and further inland by changing the jet stream and storm track. The blob appears to loosing strength but it should be watched to see determine if it will be remain a factor this year. More info on the Blob and the RRR from here: https://en.wikipedia.org/wiki/The_Blob_(Pacific_Ocean)  and  https://en.wikipedia.org/wiki/Ridiculously_Resilient_Ridge

The Analogs

Analog years are seasons with a similar upper atmosphere and ENSO, El Nino/La Nina conditions.  Forecasters use these similar years to help define the pattern for the coming season.  These years are only part of the forecasts. While no two years are alike, the analogs help provide an idea of the coming season and the possible pattern. This year’s analogs are from years with a neutral or with a weak La Nina that occurred after a season with a strong El Nino year.

Here are some of the most common analog years being discussed, along with the total snowfall and average temperatures for the winter season (side note, both Toronto and Ottawa all had white Christmas in these analog years, more on that later);

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The Teleconnections

There are other complex series of atmosphere conditions that have an impact on the weather and the pattern.  You can have cold in place and moisture available but without some of the teleconnections cooperating, you can have storms simply not develop or stay away from certain areas and favour other areas.  The Arctic Oscillation (AO) and North American Oscillation (NAO) are examples.  Both explained here: http://climate.ncsu.edu/climate/patterns/NAO.html   Usually you want a Negative AO and a Positive NAO for your best chance at snowy winter in Ontario, but too much of either phases can be too much of a good or bad thing.  Getting at least one of these conditions to cooperate is helpful.

So what does this all mean?

General season

Well for starters, I am predicting, as are most meteorologist, a more typical style Canadian winter this year.  This means some periods of pretty cold temperatures and decent snowfalls.  I think there will be some warmth left over in November with the potential for a colder pattern setting up near the end of the month.  However I think we might see another warm up again in early to mid-December before winter really sets in.  The question will be how long the warmth hangs around in December.  We have suffered warm Decembers the last couple years.

The Cold temperatures

The brunt of the cold this winter looks to be confined to the Prairies, but Ontario may also see some colder periods compared to normal, especial Northwestern and South Western Ontario.  The East coast will likely stay near normal, while the West stays cold (except the BC Coast).

The Storms

Storms across the East will likely be more frequent and possibly strong, especially towards the East Coast (Southern Quebec, New Brunswick, Nova Scotia).  The Prairies might end up drier with the strong cold flow over the region.

So what could go wrong?

Now when I say what could go wrong, I mean as a Snowstorm lover, so really most non winter lovers would call this section; what could go RIGHT…

So with the extent of the cold taking hold of the Prairies later in January and February there is always the chance of suppression of storms for Ontario. This means snowstorms may stay south and east of Ontario in January February as the cold upper level heights could force the storms away from the area if the cold starts to entrench the region.  However if it manages to stay nearby but not in the region it could actually help feed storms cold air.

The other issue is the models could be on to something with the warmth and we get a trough in place out in the west in the Pacific with the blob that either sets up Pacific air across the continent or set ups a blocking pattern in the east with storm missing the region to the south.  The other scenario is the heat returns in December allowing more rain than snow and another year with a warm December.  However these above scenarios look less likely currently.

The Other Forecasts

Here is a look from some of the other forecasts:

From The Weather Network:capture2

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From Brett at Accuweather:capture4

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From Bigmt on the Accuweather Forum (Yes, he is back!):capture6

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Part two will breakdown my forecast by region…coming this weekend…

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