Do you believe that this 2009-10 winter will be a strong one? (snowing, average)

[Jammie]

Icy, that's cute.

Some of you have had an exceptionally warm summer, but we've had a very chilly summer. Our early autumn isn't doing too great either, but I think things will mellow out. I HOPE they will.

Case in point~our avg. right now is 69 deg. I believe we hit 52 Sat. and 55 Sun. Something like that anyway. We kinda lost out on a summer this year.

[GraniteStater]

Winter will be BRUTAL from the Great Lakes on east. I have many reasons for why I think so... The PDO is its negative phase (after being positive for much of the late 80s and most of the 90s). The sunspot activity is still in a very low state. The El Nino event looks to be weak at best and west basin centered. Historical analogs suggest weak intensity El Ninos that are west basin centered support average to below average temperatures throughout much of the US. Also, for the past several winters the NAO and AO indicies have often trended into the negative range so that would also imply more storminess and colder than average temperatures for the eastern US.

In conclusion my general forecast for the upcoming winter is...

Northeast- below average temperatures and above average snowfall.
Southeast- below average temperatures and average precipitation
Upper Midwest (Great Lakes)- below average temperatures and above average snowfall
Plains- average to above average temperatures and below average precipitation
Northwest- above average temperatures and below average precipitation.
Southwest- above average temperatures and average precipitation.

[wavehunter007]

….Winter will be AVERAGE in most regions of the USA this winter. I think the West Coast will see above normal precipitation, however. I think the current weak El Nino will slowly strength as we approach the start of the cold season in November, which will moderately mitigate some of the cold east/south of the Great Lakes this winter. The slowly strengthening El- Nino will also bring heavier precipitation to the southwest and perhaps the southeast. It may end up warmer than normal in the southeast if the El-Nino gets stronger faster than anticipated. The NAO was “all over the place last winter” and will do the same this winter (as is always the case - the NAO never stays in one phase for long).

Typical heavy mountain snows in the West…while the Great Lakes/Upper Midwest/and parts of the interior Northeast might see a few early December modest snows. Along the Atlantic coastal plain … Atlantic Ocean temperatures are running a bit above normal (ocean still near 68 - 70 F off the New Jersey coast)…this combined with even a weak El – Nino, will not allow much snow below 40 latitude (Long Island, NY southward). At least until early January, that is. Sorry folks, typical green Christmas in NYC and DC again (lol).


Northern Plains/Upper Midwest /Great Lakes- Normal to a bit above normal snowfall and average to modestly below average temperatures.

Interior Northeast (West Virginia northeast to Boston, MA) - average temperatures and average snowfall.

Coastal Northeast/Atlantic Coastal Plain (Southern Rhode Island south to Richmond, VA) - average to slightly above average temperatures and average precipitation.

Southeast (south of Richmond through Carolinas)- average to slightly above average temperatures and average precipitation.

Florida - average temperatures and average precipitation.

Northwest- average temperatures and average precipitation.

Southwest- above average temperatures and above average precipitation.

[GraniteStater]

Originally Posted by wavehunter007

….Winter will be AVERAGE in most regions of the USA this winter. I think the West Coast will see above normal precipitation, however. I think the current weak El Nino will slowly strength as we approach the start of the cold season in November, which will moderately mitigate some of the cold east/south of the Great Lakes this winter. The slowly strengthening El- Nino will also bring heavier precipitation to the southwest and perhaps the southeast. It may end up warmer than normal in the southeast if the El-Nino gets stronger faster than anticipated. The NAO was “all over the place last winter” and will do the same this winter (as is always the case - the NAO never stays in one phase for long).

Typical heavy mountain snows in the West…while the Great Lakes/Upper Midwest/and parts of the interior Northeast might see a few early December modest snows. Along the Atlantic coastal plain … Atlantic Ocean temperatures are running a bit above normal (ocean still near 68 - 70 F off the New Jersey coast)…this combined with even a weak El – Nino, will not allow much snow below 40 latitude (Long Island, NY southward). At least until early January, that is. Sorry folks, typical green Christmas in NYC and DC again (lol).


Northern Plains/Upper Midwest /Great Lakes- Normal to a bit above normal snowfall and average to modestly below average temperatures.

Interior Northeast (West Virginia northeast to Boston, MA) - average temperatures and average snowfall.

Coastal Northeast/Atlantic Coastal Plain (Southern Rhode Island south to Richmond, VA) - average to slightly above average temperatures and average precipitation.

Southeast (south of Richmond through Carolinas)- average to slightly above average temperatures and average precipitation.

Florida - average temperatures and average precipitation.

Northwest- average temperatures and average precipitation.

Southwest- above average temperatures and above average precipitation.

Most sources that I have seen indicate that El Nino will not get any stronger than a weak to moderatly week state. I just don't think it will have an overwhelming influence on the prevailing weather patterns this winter. The early push of winter with several feet of snow in the Northern Rockies should be a good indication that this coming winter will be harsher than last year. I think the Intermountain West could have a good snow year. In terms of the jet stream being more zonal due to El Nino, I don't think it will be a strong influence. I think we will cycle between a higher amplitude meridonal flow and the aleutian low as is typical of winter. I do think the potential exists for a few prolonged periods of a Greenland Block, -NAO, and cross-polar flow. If the El Nino event does not strengthen by next month then I will stick to my early predictions for the winter. Also, check the latest SST anomaly maps per the CPC. The warm anomalies in the east basin of the Pacific are shrinking substantially. Fall is a definite transition period for ENSO events, but it still looks week to me ATM.

[wavehunter007]

Originally Posted by GraniteStater

Most sources that I have seen indicate that El Nino will not get any stronger than a weak to moderatly week state. I just don't think it will have an overwhelming influence on the prevailing weather patterns this winter. The early push of winter with several feet of snow in the Northern Rockies should be a good indication that this coming winter will be harsher than last year. I think the Intermountain West could have a good snow year. In terms of the jet stream being more zonal due to El Nino, I don't think it will be a strong influence. I think we will cycle between a higher amplitude meridonal flow and the aleutian low as is typical of winter. I do think the potential exists for a few prolonged periods of a Greenland Block, -NAO, and cross-polar flow. If the El Nino event does not strengthen by next month then I will stick to my early predictions for the winter. Also, check the latest SST anomaly maps per the CPC. The warm anomalies in the east basin of the Pacific are shrinking substantially. Fall is a definite transition period for ENSO events, but it still looks week to me ATM.

Forecasting the strength and position of any EL Nino is quite challenging it seems. The Pacific Ocean is the most dynamic ocean basin on the plant. Pin-pointing how strong an atmospheric phenomenon that size will be…two or three months out…seems more like a shot in the dark to me. Nevertheless…it is well known that even the weakest El Nino…generally promotes a more moderate winter in the eastern half of the USA (east of about 95 longitude).

As far as the NAO, well this is the poster child for the dreams of winter fans in the USA…and for good reason. The North Atlantic Oscillation (NAO) is considered to be a player in the winter weather across North America. However, even here…there is more than meets the eye at first glance:

The concept is pretty simple: When the NAO is negative, there is a block at the higher latitudes. The colder air over sub-polar and polar Canada is then diverted (somewhat) down into the temperate and subtropical latitudes of North America (USA/Mexico). So we can make the case that in winter…colder air is diverted south into the United States during a negative NAO. However, there are many issues with the neg phase of the NAO that are often over looked. When the typical Weather Channel or AccuWeather winter weather hype machine is full swing…they seem overlook that there are several factors that mitigate the NAO’s effect historically ...especially in the negative phase. As they say so often…the devil is in the details:

1) The NAO has a tendency to never stay in the same phase…especially the strongly negative one… for very long history shows. In fact, although the NAO is seasonally more active in winter over the Northern Hemisphere, there can be several bouts when the NAO goes negative in the warm season (look at this past spring/early summer!). Still, it is unusual for the NAO to remain strongly negative for more than 14 days on average.

2) When the NAO is negative (there is a strong block)…the air masses that are driven down into the USA…especially the ‘eastern USA”…. may be colder than normal...but they are also “drier “ than normal. So moisture must come from elsewhere for big snows in the far eastern USA. Yet, winter moisture is very transient in the eastern USA because of the prevailing dry NW flow (winter monsoon) out of northwestern Canada. Keeping the “cold air in place” and getting the “moisture close”… is generally a fairly fleeting situation. Just for an example...NWS Phildelphia did a study of neg phase NAO years...and found that the City of Phildelphia averaged drier weather overall in neg phase NAO winters compared to normal or neutral phase years. Also the NAO can often be too negative …which pushes storms too far south, resulting in just cold and dry conditions in places like the upper Midwest/Great Lakes/northern New England.

3) Finally, if we analyze the long-term trends in the winter (averaged over Dec-Jan-Feb) phase of the NAO… we see a strong trend towards the positive (warm) phase (bad for snow) in the long term. Some folks in climate science think that since the area of late summer Arctic Sea ice is now much smaller than in past decades, and looks to stay the same for the foreseeable future…the NAO will only rarely go negative of any prolonged length of time. The constant reference to the 1966 to 1978 period and how severe winters were in the eastern USA was a time when the late summer Arctic sea ice was at a 70 year high (possible much longer). It’s quite possible…the 1960’s and 1970’s (when there were several negative NAO episodes, and cold and snowy winters), may have been an anomaly (say a 100 to 200 year event).


Still, it’s going to be fun to watch how it all shapes up this winter…

[I LOVE NORTH CAROLINA]

Do you believe that this 2009-10 winter will be a strong one?

I can always hope

[marmac]

I'll pass on predicting the winter.

When I tried in the past, it seemed I always ended up wrong.

[Jammie]

Originally Posted by marmac

I'll pass on predicting the winter.

When I tried in the past, it seemed I always ended up wrong.

So make your prediction and we'll just go with the exact opposite. Kind of like when I choose a sport's team. They ALWAYS end up losing. There's even a few people who ask me who will win and I tell them and they bet the opposite way. They usually win their bet.

[GraniteStater]

Originally Posted by wavehunter007

Forecasting the strength and position of any EL Nino is quite challenging it seems. The Pacific Ocean is the most dynamic ocean basin on the plant. Pin-pointing how strong an atmospheric phenomenon that size will be…two or three months out…seems more like a shot in the dark to me. Nevertheless…it is well known that even the weakest El Nino…generally promotes a more moderate winter in the eastern half of the USA (east of about 95 longitude).

As far as the NAO, well this is the poster child for the dreams of winter fans in the USA…and for good reason. The North Atlantic Oscillation (NAO) is considered to be a player in the winter weather across North America. However, even here…there is more than meets the eye at first glance:

The concept is pretty simple: When the NAO is negative, there is a block at the higher latitudes. The colder air over sub-polar and polar Canada is then diverted (somewhat) down into the temperate and subtropical latitudes of North America (USA/Mexico). So we can make the case that in winter…colder air is diverted south into the United States during a negative NAO. However, there are many issues with the neg phase of the NAO that are often over looked. When the typical Weather Channel or AccuWeather winter weather hype machine is full swing…they seem overlook that there are several factors that mitigate the NAO’s effect historically ...especially in the negative phase. As they say so often…the devil is in the details:

1) The NAO has a tendency to never stay in the same phase…especially the strongly negative one… for very long history shows. In fact, although the NAO is seasonally more active in winter over the Northern Hemisphere, there can be several bouts when the NAO goes negative in the warm season (look at this past spring/early summer!). Still, it is unusual for the NAO to remain strongly negative for more than 14 days on average.

2) When the NAO is negative (there is a strong block)…the air masses that are driven down into the USA…especially the ‘eastern USA”…. may be colder than normal...but they are also “drier “ than normal. So moisture must come from elsewhere for big snows in the far eastern USA. Yet, winter moisture is very transient in the eastern USA because of the prevailing dry NW flow (winter monsoon) out of northwestern Canada. Keeping the “cold air in place” and getting the “moisture close”… is generally a fairly fleeting situation. Just for an example...NWS Phildelphia did a study of neg phase NAO years...and found that the City of Phildelphia averaged drier weather overall in neg phase NAO winters compared to normal or neutral phase years. Also the NAO can often be too negative …which pushes storms too far south, resulting in just cold and dry conditions in places like the upper Midwest/Great Lakes/northern New England.

3) Finally, if we analyze the long-term trends in the winter (averaged over Dec-Jan-Feb) phase of the NAO… we see a strong trend towards the positive (warm) phase (bad for snow) in the long term. Some folks in climate science think that since the area of late summer Arctic Sea ice is now much smaller than in past decades, and looks to stay the same for the foreseeable future…the NAO will only rarely go negative of any prolonged length of time. The constant reference to the 1966 to 1978 period and how severe winters were in the eastern USA was a time when the late summer Arctic sea ice was at a 70 year high (possible much longer). It’s quite possible…the 1960’s and 1970’s (when there were several negative NAO episodes, and cold and snowy winters), may have been an anomaly (say a 100 to 200 year event).


Still, it’s going to be fun to watch how it all shapes up this winter…

You make some good points.

Do you have a meteorology background?
I took some courses in meteorology when I was in college before switching my major. (I couldn't meet the very strict math requirement).

[dude1984]

Originally Posted by wavehunter007

Forecasting the strength and position of any EL Nino is quite challenging it seems. The Pacific Ocean is the most dynamic ocean basin on the plant. Pin-pointing how strong an atmospheric phenomenon that size will be…two or three months out…seems more like a shot in the dark to me. Nevertheless…it is well known that even the weakest El Nino…generally promotes a more moderate winter in the eastern half of the USA (east of about 95 longitude).

As far as the NAO, well this is the poster child for the dreams of winter fans in the USA…and for good reason. The North Atlantic Oscillation (NAO) is considered to be a player in the winter weather across North America. However, even here…there is more than meets the eye at first glance:

The concept is pretty simple: When the NAO is negative, there is a block at the higher latitudes. The colder air over sub-polar and polar Canada is then diverted (somewhat) down into the temperate and subtropical latitudes of North America (USA/Mexico). So we can make the case that in winter…colder air is diverted south into the United States during a negative NAO. However, there are many issues with the neg phase of the NAO that are often over looked. When the typical Weather Channel or AccuWeather winter weather hype machine is full swing…they seem overlook that there are several factors that mitigate the NAO’s effect historically ...especially in the negative phase. As they say so often…the devil is in the details:

1) The NAO has a tendency to never stay in the same phase…especially the strongly negative one… for very long history shows. In fact, although the NAO is seasonally more active in winter over the Northern Hemisphere, there can be several bouts when the NAO goes negative in the warm season (look at this past spring/early summer!). Still, it is unusual for the NAO to remain strongly negative for more than 14 days on average.

2) When the NAO is negative (there is a strong block)…the air masses that are driven down into the USA…especially the ‘eastern USA”…. may be colder than normal...but they are also “drier “ than normal. So moisture must come from elsewhere for big snows in the far eastern USA. Yet, winter moisture is very transient in the eastern USA because of the prevailing dry NW flow (winter monsoon) out of northwestern Canada. Keeping the “cold air in place” and getting the “moisture close”… is generally a fairly fleeting situation. Just for an example...NWS Phildelphia did a study of neg phase NAO years...and found that the City of Phildelphia averaged drier weather overall in neg phase NAO winters compared to normal or neutral phase years. Also the NAO can often be too negative …which pushes storms too far south, resulting in just cold and dry conditions in places like the upper Midwest/Great Lakes/northern New England.

3) Finally, if we analyze the long-term trends in the winter (averaged over Dec-Jan-Feb) phase of the NAO… we see a strong trend towards the positive (warm) phase (bad for snow) in the long term. Some folks in climate science think that since the area of late summer Arctic Sea ice is now much smaller than in past decades, and looks to stay the same for the foreseeable future…the NAO will only rarely go negative of any prolonged length of time. The constant reference to the 1966 to 1978 period and how severe winters were in the eastern USA was a time when the late summer Arctic sea ice was at a 70 year high (possible much longer). It’s quite possible…the 1960’s and 1970’s (when there were several negative NAO episodes, and cold and snowy winters), may have been an anomaly (say a 100 to 200 year event).


Still, it’s going to be fun to watch how it all shapes up this winter…

Intersting stuff. I am hoping for a cold and dry winter.

Originally Posted by BPerone201

I think the Mid-west see's less snow but still stays very cold.

I hope so.

Originally Posted by Icy Tea

The upper midwest is getting off to a chilly start.
You know that's why Chicago was turned down for the 2016 Summer Olympics, the cool summer. They would have had to called it the "Without a Summer Olympics".

It would have been the Autumn Olympics.