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Winter on the way


Snowguy716

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While the United States has warmed in every month of the year since 1895, September and October have not warmed at all and have in fact cooled in many regions.

My theory is that with increased ocean temperatures comes an increased frequency of El-Ninos, which tend to favor cooler September/October periods before warming up in November and December.

With an expected El-Nino winter coming up, snow in mid-October has not surprised me. In mid-December we'll probably be begging for it.

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El Nino is a slowing of westerly trade winds in the equatorial Pacific. The winds that usually blow from South America towards Australia pull the sun heated water further west, which allows cooler water to upwell in its place, keeping the water off the South American coast cooler.

During an El-Nino, this process slows down, allowing more warm water to stay further east. This allows for more development of thunderstorms and means heavier rain in coastal Peru.

It also amplifies the subtropical jet and causes it to split following a track over the southern U.S. This means more storms for southern California, the desert Southwest, and the Southeast. Along with these stronger systems, cooler weather can accompany it.

In the north, a weaker polar jet allows warmer west winds to prevail keeping things dry and warmer than normal. Winters 1982/83 and 1997/98 are good examples of an El Nino winter.

While El Nino weakens the trade winds in the Pacific, it strengthens with easterly trade winds in the Carribean and western Atlantic. This acts to tear apart tropical waves before they can develop into hurricanes/tropical storms. 2006 has been a good example of that, having much fewer storms than anticipated.

La Nina has all the opposite effects. Stronger westerlies allow cooler water to upwell in the eastern Pacific, causing drought conditions in coastal Peru. This amplifies the polar jet and keeps storms slamming into the Pacific Northwest and Alaska keeping the northern U.S more active and usually colder than normal while the south is typically drier and warmer than normal during these winters.

La Nina also weakens the easterly winds in the western Atlantic, allowing storms to develop without shearing winds. 2005 was a good example of this.

There are also other cycles that affect the strength and frequency of el nino/la ninas (Or referred to as ENSO El Nino Southern Oscillation). The PDO, or Pacific Decadel Oscillation, is a recently discovered cycle that switches every 25-30 years.

During a positive phase of PDO, warmer water builds up in the eastern Pacific north of the Equator while cool water builds in the northwest Pacific. We have been in such a phase since 1975, which is more favorable for El-Nino conditions.

The negative phase, which pools warmer water in the northwest Pacific and cooler water in the eastern Pacific, favors La Ninas, such a cycle was experienced from 1945-1975.

This is believed to be at least partly responsible for the stagnation in warming temperatures during that time period. The upwelling of cooler water in the Pacific kept world temps down further than they might have been had the cycle not occured.

Also very important in winter forecasting is the Arctic Oscillation (positive phase means low pressure at the north pole, keeping cold air locked up north with strong west winds at the mid latitudes, meaning warm and dry for the U.S and cold for eastern Canada/Greenland and negative which is the opposite, allowing arctic air to dive southward rather than scream eastward.) A stubbornly positive phase took hold in the late 1980s and lasted until around 2002. THis is believed to have contributed ever faster sea ice melt as warm, salty water was pulled into the arctic through Europe and cooled NE Canada and Greenland a bit.

All these cycles are very important to accurately predicting a winter forecast. Of course they are simply reactive cycles to our global climate system, so they have no net effect on climate change other than delaying or speeding up the process temporarily.

Things like greenhouse gas emissions, solar cycles and volcanic eruptions have a much higher impact on global climate trends. And that's a fact, whether you want to believe it or not.

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While the United States has warmed in every month of the year since 1895, September and October have not warmed at all and have in fact cooled in many regions.

My theory is that with increased ocean temperatures comes an increased frequency of El-Ninos, which tend to favor cooler September/October periods before warming up in November and December.

With an expected El-Nino winter coming up, snow in mid-October has not surprised me. In mid-December we'll probably be begging for it.

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Nah.. you're from Georgia...

There's a chance you could have snow for Thanksgiving. Of course that's a very very slight chance, but El-Ninos tend to mean cooler and wetter than average winters in the southeast.

Oh, and it's snowing quite heavily outside right now. And like usual during winter, it snows when it isn't forecasted.. and only when it's not forecasted.

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Nah.. you're from Georgia...

There's a chance you could have snow for Thanksgiving. Of course that's a very very slight chance, but El-Ninos tend to mean cooler and wetter than average winters in the southeast.

Oh, and it's snowing quite heavily outside right now. And like usual during winter, it snows when it isn't forecasted.. and only when it's not forecasted.

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I do hope this winter brings more snow than last year. We had practically NO snow last year. 2 years ago, we had like 8 inches of snow the first week of December.

Hey, any of you fellow UP'ers from the Michigan area, what's the chances of my running into bad weather in Detroit the week of Thanksgiving? I have to connect thru the airport there a couple of times that week..

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There will undoubtedly be a massive blizzard that shuts down the entire central U.S. and you will spend Thanksgiving eating turkey dinner at Denny's.

:)

You should be fine. Small delays are possible with snowfall because of de-icing, but other than that, I think Detroit is pretty safe from major snow storms around Thanksgiving on any given year.

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Well we kinda have a slight problem. Winter's on the way, I live with my grandmother and she gets very cold and she can make the house very hot... I'll have the window open with the fan in it to keep myself cool in the winter if necessary. But our only means of heat besides the kitchen oven is an old Durotherm, I think that's the name, from the 1950s and we recently had a slight leak from it... kerosine... The stove was on at the time the leak started. It's since been fixed a few days ago, but we haven't lit it yet. It's going to get cold again soon and well, this is one problem with winter on the way. Anyone know a good way to get kerosine out of floorboards? Dilute with water? Scrubbing?

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