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Seasonal Outlook: Winter 08/09 Well, first things first. I make this claim every year and this year is no different. If there is one item that you take with you after reading this outlook it should be: There is no way to reliably predict the weather on a seasonal scale! Those of you who have been following my site know that I have always been pretty low key and skeptical of any seasonal forecast- even my own. In fact I like to use the work "outlook" as I feel "forecast" should be reserved for something that has a little more proven science behind it. For those of you that are relatively new to the site, you might want to click here and read my "Soap Box Speech on Seasonal Forecasting". For those of you that have read it before, no need to again- it is the same as in years past. Now with that said, lots of folks still want me to produce a winter forecast, so here it is:
Much like last year there looks to be some hope of good news for snow lovers across the northern US. Not that I am guaranteeing all of the northern US will see above average snowfall and a colder than average winter, but I think there are several factors occurring that all point to enhanced chances that at least a good portion of the Midwest will see average to below average temps and that will lead to average to above average snowfall. I see 2 main contributing factors to chances for a decent winter in the Midwest and they are: 1) The absence of an El Nino. Sea Surface Temps in the Equatorial Pacific look to remain in what is called "ENSO Neutral" through the winter months, which means neither an El Nino or La Nina look to occur. There is a slight chance that a weak La Nina could return, but if that were to occur, it would not lead to conditions that were any less favorable for snow and cold in the Midwest than are seen with the ENSO Neutral. 2) The presence of average to above average temps across the Midwest so far this Autumn. Of these two, the absence of an El Nino is the strongest argument, with the other factor lending some hope, but not a lot of strong scientific support I believe that many already know about the dreaded El Nino and it's effects on winters in the Midwest, but for those that would like a general picture of what El Nino and La Nina typically does to the weather across North America in the winter, they can view Figure 1. It should be noted that El Nino and La Nina do not always produce these types of weather anomalies, but do up the odds considerably. The second point I make is one that I have been using for a few years now and is not one that can be a great indicator of the upcoming winter, but I have found it to be of some use. That factor has to do with the idea that mother nature can only produce a certain weather anomaly for so long before she has to swing things in the other direction. For example, no drought lasts forever, no heat wave lasts forever, no flood last forever. In many cases, one weather anomaly actually ends up being replaced by an anomaly that is the opposite and can be similarly dramatic. While the summer of 2008 was absent of any real severe heat, so far this meteorological autumn (since September 1) has produced average to above average temps across a good portion of the Midwest. It is my opinion, based on some evidence in the past, that a warm autumn can lead to a colder and snowier than average winter. The data to support this is not overwhelming, but I see lots of snowlovers get excited when October turns cold and snowy across the upper Midwest (like 2 years ago), only to be followed by a winter that turns out to be a bust (like 2 years ago). There have also been years in which autumn temps were milder than average (78,79,94,01,07) and then as we worked through the middle of November a shift in the overall jet stream configuration occurred and that led to below average temps and above average snowfall across the Midwest. It can be a little nerve wracking to have to endure, but I have noted that the longer the warm anomaly can persist into October or even early November, the better the flip seems to turn out. I would not even be overly concerned if we get to very early December and the flip has not occurred. Although if the flip does not occur through the middle to end of December, then all bets are off! Also, if the flip occurs at the middle to end of October, that is not as good as early to middle November, but there is still no reason to hit the panic button. It may just be a case where the flip has occurred earlier and could then persist through the winter. So in a nutshell, there are several reasons to be optimistic about this winter. Obviously there are no guarantees and even with in a colder and snowier than average winter, there are the occasional thaws- especially in areas south of the Northwoods. So folks in places like southern MN, WI and lower MI as well as IA and northern sections of IL, IN and OH should not get your hopes up that temps will fall to below freezing in December and stay there until March, with snow on the ground that entire time period. It just does not happen that way, even in the coldest of winters. Below are the details to the forecast for the different regions of the northern US: REGION 1 – The Northwest Midwest: I believe this region has a very good chance to see at least average snowfall and a lesser chance, but still a chance that snowfall will be above average for the winter. Most of this region saw average to below average snowfall last year and is still overdue for the kind of winter that snowlovers living in these areas dream about. I think that the odds are greater than average that the storms that roll through the area could produce larger than expected snows. I also expect lake effect snows in the UP to run average to above average as well. Overall I feel as confident or even a bit more confident that snows will be average to above, with temps average to below in this region as I did for last season. REGION 2 – The Southeast Midwest: Portions of this region (eastern
IA, the southern 1/2 of WI and sections of northern IL) saw record or near
record setting seasonal snowfall last winter. This causes some fear for me for
two reasons. The first fear is that folks living in these areas may look back to
last winter and think that it is the way winter is suppose to be in these areas,
rather than realize that snowfall was at or near record levels, so was snow
depth
and the persistence of snow on the ground. That could lead to a false sense of
reality and if an even average winter of snowfall and temps are seen, it will be
perceived as a warmer and less snowy winter. The other factor that worries me is
that in my observations, it is difficult to produce back to back banner snow
seasons. Just as I believe stringing together winters with less snow and cold
increases the likelihood that Mother Nature will even things out, it works the
opposite way too. That should not be taken to mean that areas that saw record or
near record snows last year should expect a winter with poor snowfall to be a
given, but I do think it ups the odds. There is hope though. The winters of the
mid to late 70's produced some very cold and snowy weather in the Midwest and in
particular, those of
77-78 and 78-79 were back to back big snow producers for many folks in the
Midwest- including this region. REGION 3 – The Northeast US: I do not see any strong signals to go one way or the other for this region. However, the past few winters in this region have been a little hit and miss. Some areas doing quite well (as was the case in northern Maine last year) while others have not seen the snows that they typically could be. I think that does increase the likelihood that much of this region could end up with average to above average snowfall, with average temps. I do think that there will be an above average number of winter storms through the region, it may just be a case of where the rain/snow line sets up and where the heaviest snow falls with each event. I guess in a nutshell most snow lovers in the Northeast US should see a better winter this year than they have in most areas in the previous years, but may still have to deal with the occasional disappointment (rain rather than snow from a storm or the occasional thaw). I see lake effect snows for these areas to run close to average. REGION 4 – The Northern Rockies: Many of these areas finally saw a good season last year. The snows came early and fell with regularity through the season and a cold and wet (snowy) spring kept some folks that live in this neck of the woods playing in the snow well into June. I see this winter as another one that holds better than average odds that snows will be average to above and temps variable, but average in the overall scheme of things. Since temps are not as big a concern in the higher terrain of the west than in other areas of the northern US, that means that another good snow play season could be in store for much of the northern Rockies. I guess my main questions with this region would be how long the snow lasts into spring. Last spring was quite unusual for these areas and the odds of that repeating for spring of 09 are fairly slim. However, I do not see the snows disappearing from most of this region any sooner than is typical. REGION 5 – The Central Rockies: This region saw a fairly good winter last year as well. Perhaps not as good as their neighbors to the north, but I do not think too may were complaining either. I see this winter to be fairly similar. Meaning records may not be broken, but I do not think there will be too much to complain about. Like last year, I believe that the further north you go the better the chances for average to above average snowfall. REGION 6 – The Pacific NW and Sierra Range: Much like last winter, I expect this area to see above average temps and average to above average precip. Thus it will be a case where elevation will play a huge role in how much snow falls. The higher the elevation the more snow. I know this is the case everywhere out west, but I guess what I am trying to say is that some places that are usually high enough to see mainly snow fall with a storm may see rains occur more than average this winter. So you will have to go even higher than you might normally have to go to hit the snow line with many of the storms this winter- especially in CA and southern OR. REGION 7 – Eastern Canada: I should really break this region into two separate regions as it is big enough. In any case, I expect the western sections of this region (Ontario mainly) to see average to above average snowfall, with close to average snowfall in Quebec and the maritime provinces. Temps across Ontario will be average to below, with the best chances for below average temps occurring the further west you go. Temps across Quebec and the Maritimes will be close to average overall.
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