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Winter Forecast for 2013/2014

INTRODUCTION

It’s that time of year again where we try to figure out what to expect for the up coming winter!

Let’s be clear, there is something about winter that brings a bit of emotion to people.  Some people love this time of year.  The first snow flake or snow storm of the year.  The smell of the air with a crisp new Arctic air mass.  Other’s absolutely hate Winter.  When I say hate, I mean, take the time to write me three pages in an email of how much they detest a storm.  So my objective as always is to explain to you in a level-headed, clear, and specific process of what I’m seeing and explain to you WHY I am putting out this particular winter forecast.

My objective is that you, the reader, gets more out of this forecast than just a map and a big snowman planted somewhere to create excitement.  I will take you from point A to B and all the way to Z in this forecast.  I will explain what can change the forecast as well as after all this is basically a five month forecast, almost half a year!  I don’t care how good of a forecaster you are, there are going to be a lot of wild cards that will show up over the next 5 to 6 months that WILL change this forecast.  My attempt is to draw out those pitfalls and explain what could happen if those uncertainties start to show up.

Oh yeah, and this forecast is completely free to everyone!

So let’s get to this!

 

FORECASTING TECHNIQUES

This forecast will use a combination of observations of current and the previous 6 months of atmospheric and thermal oceanic states along with lessons learned from previous years.  The goal of this forecast is to not only detail what this forecaster thinks will happen but also what could go wrong in the forecast.

I know there is a significant use by some to use previous years as the sole process for forecasting a winter.  For example, finding years with similar ENSO states or similar teleconnections like the AMO, NAO, or any other mix.  While studying previous winters and/or storms is a VERY important factor in any forecast, one must understand that each winter is unique and that the use of previous years to make a forecast point will not be used that there tends to be a great misunderstanding in how to use this data.

DRIVERS VS ENHANCERS

For months I’ve been explaining to Premium Members why designating which factors in the atmosphere are the drivers or forcing mechanisms and which ones will enhance the overall pattern in place.  I’m not sure if other meteorologist see the atmosphere as I do in this frame, but this is a process that I’ve developed over the past 15 years studying the atmosphere.

The drivers and enhancers of a winter weather pattern change from year to year and even month to month.  A perfect example is El Nino Southern Oscillation.  In some years the El Nino or La Nina can be very strong leading to an overwhelming influence on the atmosphere and overriding other factors that could influence a weather pattern.  Sometime the influence of the stratosphere is a key indicator that influences the weather pattern.  In other years, the weather pattern can feature weak or neutral characteristics.

The forecasting of the atmosphere is a process of trying to figure out how chaos works out.  No forecast is going to be 100% correct.  Heck, some meteorologist just pull off the old partly cloudy with a 50% chance of rain bit.  Talk about wishy-washy.  Stating that, if you are able to separate the driving primary influences on a weather pattern from the features that simply will enhance the pattern, you can then put together a forecasting that includes factors from all aspects of the atmosphere.

This year’s driver is clear the stratospheric anomalies setting up over the northern Hemisphere that is setting up the Polar/Arctic jet streams to feature some impressive high latitude blocking scenarios.  The enhancers to the weather pattern include snow cover over North America, Sea Surface Temperatures in the Atlantic and Pacific, ENSO, and the MJO phases.

 

STATE OF THE STRATOSPHERE AND INFLUENCES ON 500 MB

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I’m going to start with the stratosphere this year because after carefully studying that atmospheric weather patterns over the past 6 months, the data clearly points to stratospheric influences controlling the weather pattern over the Northern Hemisphere.    Note that through this summer, factors like the MJO and ENSO have been rather benign, as I’ll discuss in future chapters.  The factor of the matter is that the one driving force that has been able to pick up when hot weather pattern would develop in the Eastern United States or when the Polar jet stream would become more amplified over the past few weeks have all been driven by stratospheric temperature anomalies in terms of location and intensity.

The key in using this factor is all about location and understanding physical properties of the atmosphere.  For example, using 100 MB for temperature anomalies can be misleading as the temperatures are influences by the tropospheric anomalies as a bit of a feed back influence which leads to contamination of reliable data.  Meanwhile, 10 MB although important to pick up potential trends, is too far high in the atmosphere to have an impact on the tropospheric level.  However, if a significant warming OR cooling event starts to develop at 10 MB, I keep an eye to see if those trends propagate to 50 MB and below.

I like to focus on 50 MB to pick up trends and potential influences on the troposphere.  Some use 70 MB as well, but I feel there are times that contamination of observational anomalies become an issue.  At 50 MB we are at the heart of the stratosphere and can clearly see where temperature anomalies are setting up and the overall state of the stratosphere itself.

Screen Shot 2013-10-21 at 9.41.49 AMThe equation above is basically what drives the stratospheric and tropospheric interaction.  The basic way of understanding the process is the look at a compressor.  When the stratosphere warms (cools), that layer in the atmosphere expands(contracts).  Remember, that the atmosphere of the Earth can not extend out into Space, thus pressure is exerted on the lower layers of the atmosphere, specifically the troposphere, where we live.  When the stratosphere expands (contracts) the heights at 500 MB decreases (expands) to balance out the mass in the atmosphere.  The warmer (colder) the stratosphere, the lower (higher) the overall 500 MB heights are.  Now, taking this basic yet important influence on the atmosphere, we know that when the stratosphere is warm, the troposphere as a whole tends to feature below normal 500 MB heights.

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Above is the observations of stratospheric temperatures versus average at 50 MB from last January to now.  Last time this year, the stratosphere as a whole averaged well below normal temperatures overall in the Fall which suggested 500 MB heights overall would tend to be above average.  This year though, the stratosphere this Fall has featured near to slightly above normal temperature anomalies and there are signs of warming taking place to above normal levels at 5 MB, 10 MB, and 30 MB.  This is a sign of weak propagation to the lower portions of the stratosphere.

So based on the overall average of the stratosphere, we are more likely to have 500 MB heights that are below normal rather than above normal.  This factor tends to support a higher potential for high latitude blocking over the Northern Hemisphere and an increase potential for strong surface low pressure systems.

However, all of these factors won’t mean anything if the warmest anomalies set up over China and Russia rather than the northern Pacific, North America, the northern Atlantic, or northwestern Europe.  We learned this lesson back in 2006 when the stratosphere as a whole was warm but the warmest anomalies set up in China leading to one of the coldest and snowiest winters in China’s long history while a very boring yet at times chilly winter too place over the United States.  Location matters in meteorology!gfs_t50_nh_f240

The latest observations from the CPC at 50 MB suggest warm anomalies are developing and have been shifting towards the Northern Pacific, North America, the northern Atlantic Ocean, and northwestern Europe.  Why is this important?

Well, remember in September when temperatures were rather toasty in the Eastern United States?  At that same time, stratospheric anomalies preceding that event featured very warm stratospheric anomalies over China and Russia while cool anomalies focused over North America.  The result was a deep trough over China and Russia that lead to a powerful upper level low, called the Polar Vortex to take up show in northwestern Russia.  The result of this pattern was a strong Pacific jet stream that carved out a trough in the West and ridge in the East.

These anomalies have now shifted and so has our 500 MB weather pattern.  This is why I was able to forecast the change in the weather pattern by mid October and what should be a chilly Halloween back in late August because I saw these changes starting to take place.  So we are seeing the shift in the stratosphere take shape that suggest below normal heights are far more likely over the northern Pacific, North America, the northern Atlantic, and northwestern Europe.

KEEP AN EYE ON THE SUN!

Those that say the sun has little impact on our weather or climate are what I like to call, wrong.  The sun has a major influence on the climate and our seasonal weather patterns.  When sun activity is low, the amount of radiation that reaches the Earth decreases.  This decrease in UVA rays allows for ozone to build up in the stratosphere, which leads to a warm stratosphere overall.  I think you see where I’m going here.

sunspotThe chart above from NASA shows the latest observations from January 2000 to now covering solar cycle 23 and the current cycle, 24.  The blue line and black dash points are observations of sun spots.  The more sun spots, the more active the sun and thus the more radiation that reaches the Earth.  In the years of 2008 through the first part of 2011, we entered a very quiet period of solar activity.  Not surprising, the stratosphere on average remained warm as ozone was able to build up in the stratospheric levels.  Last year, we entered a more active period for the sun, called solar cycle 24 which lead to more UVA rays to enter the stratosphere and break down the ozone thus leading to cooling.  However, note what is happening now!

We are supposed to be at the peak of Solar Cycle 24 where our sun becomes rather active.  The red line was the forecast for Solar Cycle 24 in which in this winter we start to see a steady decline.  If I was looking at this forecast in the Summer I would say that the stratosphere is likely to be rather chilly give we are around the peak of solar activity.  However, the reality is that the sun is VERY quiet for a peak and that activity is crashing well below forecasted values, almost to the points we have seen back in 2003.  This decreasing activity from the sun strongly suggest that the warm stratosphere is here to stay as ozone is able to build.

What this says about the next several years are uncertain as our understanding of solar physics is still rather limited.  However, we have not seen this lack of solar activity in over 200 years and the influences of the sun on our stratosphere and thus the troposphere can not be ignored any longer.

The sun is becoming quiet and that means that the 500 MB jet stream is likely to be rather amplified this winter.

STRATOSPHERIC CONCLUSIONS

Based on the observations above and what we know about atmospheric physics, the stratosphere is likely to feature above normal stratospheric temperatures that will lead to below normal 500 MB heights throughout the northern Hemisphere.  The solar activity is expected to be weak and thus the build up of ozone can be expected.  The latest trends of the stratosphere suggest below normal heights will be most amplified over the northern Pacific, North America, the northern Atlantic, and northwestern Europe.

Factors that can change the forecast include an unexpected jump in solar activity that would lead to rapid cooling of the stratosphere and a weakening in high latitude blocking over the northern latitudes.  Also, a shift of warmer anomalies towards Eurasia which would lead to the Polar Vortex dropping into western Russia.  This factor would promote a powerful Pacific jet stream that would drive a warm Pacific air mass into the United States.  At this time, these factors are not expect but remain a possibility.

SEA SURFACE TEMPERATURE ANOMALIES, HURRICANES, AND EL NINO SOUTHERN OSCILLATION

anomnight.10.21.2013

Next we must examine the thermal dynamic nature of our Oceans.  This is a factor that be either a driver OR an enhancer to the overall atmospheric pattern.  When we see an El Nino (warmer than normal tropical waters) or La Nina (colder than normal tropical waters) develop, there must be consideration in how these factors influence our weather pattern.  Not only would an El Nino or La Nina the presence but the strength of these features would have a profound influence on interaction of jet streams and their alignments over North America.

This year we have an oceanic environment devoid of a clear El Nino Southern Oscillation (ENSO) state.  Over the past 6 months ENSO has remained neutral for the most part wavering between -0.5C and 0.5C.  The most significant influence on ENSO has been state of the PDO which also has wavered of late from warm to cold and back again towards a warm state.

The Atlantic in the meantime has remained very warm from the Gulf of Mexico to the northern Atlantic.  Meanwhile, the Atlantic Hurricane Season remains overall rather quiet and no where near the activity that was expected from the National Hurricane Center.  The lack of strong hurricanes this season has been striking.

ENSO STATE

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As stated above ENSO remains neutral those far this Fall and I have not been able to find any suggestion of an El Nino or La Nina developing for this winter.  While there are clearly models like the CFS2V suggesting that a very weak El Nino could develop, there as been little indication of such development for the supportive lower and mid level wind patterns to support such a development.  On average through this Fall, NINO 1+2 which is around 100W to 120 W has been rather cold with a range of -0.1C to -1.3C over the past 4 months.  In fact, the cold nature of NINO 1+2 has severely limited the development of tropical low pressure systems in the eastern Pacific this Summer.  Meanwhile, NINO 4 around 170E to 170W has remained on the warm side ranging from 0.0C to 0.5C above normal through the same 4 month period.  There has been little change in this dynamic of late.

The above normal Sea Surface Temperature Anomalies (SSTA) from 170W on to 120E is an important observation.  There is clearly an enhancement of rising air in these locations leading to a string of powerful typhoons (we call them hurricanes) that have plagued the western Pacific from China to Japan.  The enhanced of convection or thunderstorms from the date line to the ocean waters south of Japan has several influences on the weather pattern as a whole.

For one, the combination of below normal heights over the Sea of Japan leads to typhoons recurving towards the northern Pacific which leads to an enhancement of a trough around the Aleutians.  This enhancement of the trough in this location is called a negative EPO pattern which corresponds to a trough in the Eastern United States.

The enhancement of convection around 180 degrees or the date line helps to enhance this trough further and also helps to enhance the Sub Tropical jet stream over the southern United States.  The combination of these factors supports below normal heights over the Southeast and Gulf Coast.

A key point here again is the lack of a true ENSO feature on mid and upper level winds.  This tells me that this  state of the tropical Pacific is not a driver of the weather pattern but is certainly an important influence.  We have already seen this influence on the weather pattern with a far more enhanced Sub Tropical jet stream this Fall over the Gulf Coast and Southeast.

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 NORTHERN PACIFIC SEA SURFACE ANOMALIES

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There has always been a debate of which comes first, the 500 MB pattern or the SSTA that drive that 500 MB weather pattern.  This is basically a chicken and the egg debate.  This year, based on observations, the changes in the 500 MB pattern driven by stratospheric influences clearly is influencing the SSTA over the northern Pacific.  Many meteorologist, myself included, keeps an eye on the SSTA in the Gulf of Alaska.  The orientation of the coldest anomalies in a negative state can have profound influences down the west coast of North America.  Conversely, warm temperature anomalies in the Gulf of Alaska can lead to powerful thermal gradients from Alaska to the coastal waters producing powerful storms that can influence the entire weather pattern over North America.

The past few weeks we have seen a shift from well above normal SSTA to below normal and now trending towards near normal to even some above normal anomalies.  Conversely, last year we saw the dominant cold state over the northern Pacific.  What the observations are telling me is that the Pacific SSTA are not a primary driver in our weather pattern but can tell us when changes in the weather pattern are taking place.  For example, the warming of the northern Pacific sea surface temperatures tells us that a trough is likely around the Aleutians as the surface winds are driving warmer water from the central Pacific into the Gulf of Alaska.  This is due to a deep low pressure system around the Aleutian Islands.

As the waters warm in the Gulf of Alaska, I expect the cold current driving down the West coast to weaken and the sea surface temperatures in NINO 1+2 to 3.4 to gradual warm to near normal levels over the next 3 weeks.  This back and forth state in the Pacific SSTA should continue through the winter and will be a calling card to pattern changes but will not cause changes in the 500 MB pattern this year.

THE ATLANTIC AND THIS YEAR’S HURRICANE SEASON

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The Atlantic Ocean this year is averaging well above normal from the Gulf of Mexico to the northern Atlantic.  First I will discuss what influences the above normal SSTA will mean for the winter then comment on the theorized link between hurricane activity and following winter seasons.

The fact that the western Atlantic and northwestern Atlantic is feature very warm SSTA is very important.  Remember, warm air rises and this very warm water around eastern North America means that air along the Gulf Coast and East coast will have a tendency to rise rather easily.  This leads to below normal surface pressures on average and also forces a need for the lack of mass at the surface to be balanced out.  These factors tend to point to cold air masses over Canada to be drawn towards the Eastern United States and also tends to force an increased potential for cyclogenesis or low pressure development along the East coast.

In terms of a negative North Atlantic Oscillation, which means a strong upper level low is around 50N and 50W with above normal heights over Greenland and northeastern Canada,  the SSTA are NOT text book but are not far off either.  The very warm waters over the northwestern Atlantic will help to drive low pressure develop and support the threat for high latitude blocking over the northwestern Atlantic.  This high latitude blocking leads to low pressure systems to develop along the Mid Atlantic coast and keeps high pressure at the surface around the St. Lawrence River Valley and northern New England, which increases the potential for winter storms along the East coast.

Given the stratospheric data discussed above, I think this winter will feature a negative North Atlantic Oscillation more often than not, however I don’t have support from the SSTA of a sustained powerful negative NAO to just dominate the weather pattern, at least not yet.  This factor is one of those features that will be volatile and will have a major influence on whether the pattern from week to week will be cold and dry or cold and wet/snowy.

CORRELATION BETWEEN ATLANTIC HURRICANES AND THE WINTER

I have been hearing about this connection between the activity and strength of hurricanes and the following winter since about late August when the forecast for an active hurricane season with several category 3 hurricanes clearly became an epic bust.  Here is why this correlation doesn’t work for this year.

The correlation from other years where driven by the fact that a weak to moderate El Nino was influencing the weather pattern over the northern Hemisphere.  An El Nino during the Hurricane Season leads to increase shear over the Atlantic due to a strong Sub Tropical jet stream that prevents tropical development to take place.

This year however, as I have shown above, we have NOT seen an El Nino take place.  In fact, in terms of the 500 MB pattern up until recently, the atmospheric environment in terms of shear has been supportive for tropical cyclone development.  What has limited this year’s hurricane season has been a layer of dry air from the Sahara desert, which I warned PREMIUM MEMBERS about back in March.  Basically, dry air from the African coast is like diamond dust on a baseball field.  The dry air limits the development of thunderstorms around a warm core low pressure system and thus prevents tropical low pressure systems from organizing and/or intensifying.  This factor is what lead to the lack of hurricane development and has no influence on the 500 MB pattern going forward for this Winter.

However, the lack of hurricane activity over the western Atlantic has lead to well above normal waters over the Atlantic Ocean as discussed above.

OCEAN DYNAMICS CONCLUSION

Based on the data discussed above, I am able to say that there will be very little to no influence from the El Nino South Oscillation this year.  The slightly warmer waters around the date line does support a weak Sub Tropical jet stream to return for the first time since 2010 but this feature will not be an overwhelming factor in setting up the 500 MB pattern going forward.

The above normal SSTA in the Atlantic though clearly suggest the potential for enhanced development of low pressure systems along the Gulf Coast and East coast this winter.  The natural thermal dynamic temperature gradient from the Gulf Stream to the coastal plain will be enhanced this year when Polar and Arctic air masses invade the eastern United States.  The atmosphere must attempt to achieve balance and the rising air over the coastal waters of the Gulf Coast and East coast point to dense arctic and polar air masses attempting to balance out this mass equation leading to the potential for major storms over the Gulf Coast and East coast.  The track of these storms naturally will depend on the week to week position of blocking patterns like the Arctic Oscillation, North Atlantic Oscillation, and Pacific-North America Oscillation.

NORTHERN HEMISPHERE SNOW COVERAGE GROWTH

nhtime-1yearThe snow coverage growth over North American has been truly impressive this year with snow coverage averaging well above normal through much of September and October.  Recently, as the 500 MB pattern continues to shift to a trough over eastern North America, there has been a return to near normal snow coverage over the northern Hemisphere.  However, if forecasts over the next 15 days from the GFS, CMC, and ECMWF are correct, much of the northern Hemisphere will feature well above normal snow coverage.

nhmapThe key areas I focus on with snow coverage growth is over northwestern Eurasia, near Siberia, and over northwestern Canada.  When snow coverage is above normal over and around Siberia, a very strong correlation shows up that supports a sustained west based negative NAO pattern along with typically cold and snowy winters for the eastern United States.  The reason for this correlation is still very much in debate.  My theory is that the above normal snowfall in these areas in the Fall supports strong Polar and Arctic air masses that interact with the warmer waters of the northern Atlantic, specifically the Gulf Stream, leading to below normal heights over the northern Atlantic and above normal heights over Greenland and northeastern Canada.

The development of a strong snow pack over northwestern and north central Canada is obviously important in terms of the winter as well as these locations are where we get our Polar and Arctic air masses.  The second half of October and early November typically features a rapid growth of snow coverage in these areas.  This Fall we already are observing a nice start to the season and again if forecasts are correct, these locations will feature above normal snowfall heading into early and mid November as well.

These factors combined with the warmer than normal Atlantic SSTA point to a weather pattern that will likely feature cold air masses driving to the south towards the Gulf Coast and East coast in regular fashion.

So you might be at this point thinking to yourself that this winter is looking cold and snowy, but before you jump to that conclusion.  Let me share with you my wild cards that could enhance OR destroy this up coming winter for all of you snow lovers.

WILD CARD NUMBER ONE

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Keep an eye on the eastern Pacific, specifically off the coast of California.  There are hints of what is called a Rex Block forming over the eastern Pacific.  A Rex Block is when a high pressure or ridge center is located directly to the north of a low pressure system or trough.  These two features feed off each other as they try to create a balance in the atmosphere.  Clue of such a block have been showing up the past 2 weeks and are now starting to materialize in the 500 MB pattern.

If such a block does develop get ready for a VERY cold winter.  This block would lock in a permanent trough around the Aleutian Islands and a ridge over the Gulf of Alaska and western North America (-EPO/weak +PNA pattern).  The upper level low to the east of California would strength and break off pieces of disturbances that will enhance the Sub Tropical jet stream.  Such a block would also warm the waters of the Gulf of Alaska and likely lead to near normal to slightly above normal SSTA in the ENSO regions.  This block is supported by stratospheric temperature anomalies.

Such a block would enhance several factors of the winter forecast.  For one, a sustained northwesterly to northerly wind pattern will be established from the Arctic circle to the eastern two-thirds of North America.  Meanwhile, 500 MB heights would be forced to stay below normal over the eastern two-thirds of the United States to help counter the ridge over the West coast.  Third, the disturbances from the upper level low off the California coast would enhance the Sub Tropical jet stream and enhance the potential for the Polar and Sub Tropical disturbances to phase along the East coast.

This block COULD be a major player and needs to be monitored if sustained.

WILD CARD NUMBER TWO

The Madden-Julian Oscillation or MJO has to be the second wild card.  The MJO has been one big pain in the neck to forecast for.  The MJO is basically a forecast where tropical forcing will develop.  For the case of winter forecasting along the East coast, the MJO phases of 7 through 1 are favorable for winter storms while 3 through 5 are not favorable.  Phases 2 and 6 are transition stages and can still support East coast low pressure development.  This is a very basic, water downed explanation, but if I went into detail, this discussion would be MUCH longer.

Screen Shot 2013-10-21 at 12.44.22 PMThrough this Fall, despite forecasts from some models, the MJO really has been a non-factor and has remained neutral thus far.  However, we have seen tendencies of the MJO to focus on the supportive phases of 6 through 1 in a constant basis.  The models though have been all over the place for the forecast for the next 30 days ranging from neutral to a powerful phase 8/1 period.  Such a period would be a clear signal for November to be on average below normal and rather stormy.

The base way to handle the MJO influences is to take a week by week approach this winter.  Once again, the MJO is a perfect example of an enhancer to this weather pattern but not a driver of the 500 MB pattern.  When the MJO starts showing signs of going into phase 7, 8, and 1; then that will be a sign that very active winter weather is likely for the Eastern United States.

WILD CARD NUMBER THREE 

Screen Shot 2013-10-21 at 12.52.06 PMOf all the factors that has me concerned in terms of the synoptic or large scale set up for this winter, I have my eyes on the Polar Vortex over northeastern Asia.

This monster upper level low is a key component in where the coldest air will be located and has a profound influence on the weather pattern.  Now, all data that I’m looking at suggest that this Polar Vortex will weaken and drop towards North America or towards the Barring Strait.  However, if there is an increase in solar activity that would lead to stratospheric cooling, then the Polar Vortex would strengthen and lock in over the North Pole.  Such a development would be a disaster for this and pretty much all winter forecasts that I’ve seen.  The result would be cold air gets locked up in Canada while a zonal Pacific pattern dominates the entire United States.  Do I expect this to happen?

No.

However, the threat does exist and thus I put this as wild card number three and one that will likely make many meteorologist and snow lovers over the East coast worry through November.

WILD CARD NUMBER FOUR

Screen Shot 2013-10-21 at 1.03.25 PMWild card number four is more about individual storms than the pattern overall.  The development of defined thermal gradients with the coastal front and the focus of lifting towards the coastal waters may lead some over the interior of the Mid Atlantic and New England to be left wanting.

On the other hand, the very warm water temperatures along the East coast will make wind direction an extremely important factor in winter forecasting in terms of precipitation type.  If you live in Belmar, New Jersey and that wind shifts to the East, you can say good bye to your snowfall forecast as warm air changes your snow to rain.  This factor will be monitored from storm to storm.  When looking at models for up coming storms, these mesoscale factors likely won’t be picked up until a day or even a few hours before the actual storm.

THE WINTER FORECAST FOR 2013/14

STORMTRACKSBased on the data above, the storm tracks above can be expected for this up coming winter.  Given the way the atmosphere is setting up, I expect a focus for low pressure development towards the East coast.  Note that the orange and green tracks are for when the North Atlantic Oscillation is in a positive state leading to a storm track further over the interior.  On the other extreme is the yellow track where the North Atlantic Oscillation is very strong leading to a suppressed storm track along the Gulf Coast and dry/cold conditions from the northern Plains to the Mid Atlantic coast and New England.

There is a high threat for a very stormy winter for the East coast, but remember that does’t mean above normal snowfall given mixing factors from storm to storm.  Also note the blue line is for Alberta Clippers that will in general be fast moving low pressure systems with an area of light snow or snow showers.  However, with the NAO is in a negative state, there is potential for one or two of these low pressure system to redevelop and rapidly develop.  The strong thermal gradient from the coastal waters to the coastal plain will also leave open the threat for mesoscale factors like inverted or NORLUN troughs this winter.

The map below is the winter forecast throughout the country. Just click on your location and there’s your forecast!

WinterForecast

The forecast above is based on the idea of a sustained negative EPO, AO, NAO pattern this winter. The heart of the cold air will be focused over the Plains, Great Lakes, and Ohio River Valley with an intense thermal gradient over the Mid Atlantic from North Carolina to Connecticut. I expect a fast start to this winter for December with a potential development after mid December. I like a relaxation in the pattern and a bit of a thaw around mid January with a more zonal weather pattern. The winter gets rocking and rolling again for late January through early March with the potential for some rather powerful winter storms. Where those storms track specific are naturally not known.

Stay ahead of the winter storms this winter with NY NJ PA Weather!