2011/2012 Snowstorm Blog

This blog will be used to document the big snowstorms this winter with storm info and satellite and radar images etc..


Oct 28-30 2011
Halloween Noreaster of 2011

In late october a shortwave dove down into the southwest and formed a surface low near the Arklatex...as the LPS moved through the southeast it produced snow as far south as Tennessee and NC...as it moved off the coast of NC it began to deepen. This is where it started to lay down the big amounts of snow in the Appalachians and the Mid Atlantic. By then it was clear that this was a fullblown Noreaster and it went on to produce as much as 31 inches of snow in the northeast. This storm was historic due to it forming really early in the season.

Extended Range Discussion

Good afternoon....If you are reading from upper east TN you probably saw your first snowflakes of the season. The teleconnection signals gave me the heads up for this little treat about two weeks before it occured. I blogged about this several blogs back in the blog titled Snow around halloween

The rain started mixing with snow here late last night and it snowed most of the night but the ground was way to warm for anything more than a coating. Freeze warnings are in affect for east TN tonight and it will stay quite cool of the night for the next few days....but a warmup looks to occur before our next significant cold front.

This cold front looks to sweep across the eastern US sometime near the middle of the month (Nov 10th thru the 16th)  and I think that this strong cold front will pretty much start our winter season...there are other signs that suggest this also. Negative NAO blocking looks to get more pronounced up in eastern Canada around  this timeframe and this will send a significant amount of arctic air into the eastern US.

We have already experienced a small taste of the -NAO/AO signal with the Baffin Block up in Canada as this is what caused the current Noreaster to run up the coast and lay a (historic for October) swath of snow down. The current pattern looks to wash out and then get even more pronounced when it builds back in. So if I had any outdoor house/yard work to do I would be doing it before it got too cold in the middle of November.

Toot

Cool And Unsettled

Good evening....After the current system moves out... high pressure will build in and make for some clear and frosty nights. Then expect cool and unsettled conditions into the extended range. Now different people analyze the weather models very differently and how you analyze those models can make or break your forecast. I have been looking over the models for a few days and I have come to the conclusion that we are headed into a very active timeframe. 

As we proceed into this more details will show theirselves but i'm affraid we have entered an unreliable guidance period at this point. The only thing that has been made clear to me is..its going to be very active with near seasonal temps. 

I will be posting more about this in a few days but thats all for now.

Toot

Winter Pattern Has Established Itself

Good morning...Got down to 29 degrees here last night with a heavy frost. Looks like a small warmup will occur early this week ahead of  a arctic airmass intrusion near next weekend. This strong cold front will stall out over the eastern U.S giving time for a large and powerful Low pressure system to form near the Arklatex and Gulf coast region late in the week.

This powerful storm will ride up this stalled out cold front somewhere along the spine of the Appalachian mtns or closer to the eastern coast of the US. After this system pulls away the coldest air of the season will infiltrate the region yet again. There is a chance that this system could lay a swath of snow down somewhere from the midwest to the east coast. I expect the mountains will get a good dose of snow also...but as the system mingles with the colder air it could also produce some wet snowflakes very far south for this time of year and somebody could get a little surprise.

I would look for the upper low to get cutoff  somewhere near the Ohio Valley as they have been doing alot this season and this system could be powerful enough to really kick in the upslope snow machine in southern Appalachians if that happens.

Welcome to the winter pattern and the first big winter cyclone of the season.

Toot

Updated Winter Outlook

Due to recent changes in the weather pattern it has become a little clearer to me of how this winter should behave..and I have a made a few changes to my winter outlook. The biggest change are the much below temps in the Great lakes region and the Ohio and Tennessee Valley areas. The cause of this is the blocking pattern that has already established itself.

The negative tendecies of the NAO/AO is already overwhelming the flow across the US and causing this chronic blocking pattern which in turn will cause the much below normal temps. The La Nina looks like it will end up weaker than what I once thought and this will also contribute to the below normal temps. But the NAO/AO is the big story here...without these the winter would be pretty mundane.

The fall season got an early start and so will the winter...we have all seen these upper level lows that have dominated the weather pattern this fall. They have been getting cutoff over the Ohio valley region. With nothing to steer them... they just stall out and keep churning precip and cold air into the northern portions of the state. Using the LRC theory.... these will be the main weather makers this winter..and alot of our snow will come from these. So I expect snowfall to be much above average in the northern half of the state this winter due to this.

I once thought the southern stream would be very active this winter... but that is looking less likely now. But when these troffs swing thru and really amplify deeply this winter there will be the chance of southern stream low pressure systems forming in and around the gulf of Mexico. There still could be alot of these..but that depends on how deep the troffs amplify and sustain theirselves this winter. I expect there will be at least a couple of these this year and those will be the bigger snow makers in the southeast. These have the potential to be major snowstorms if the PNA cooperates and this is where the southern sections of the state will get their slightly above average snowfall totals from.

I expect most of our winter weather in the month of December as -NAO winters usually feature a very snowy december's here. Now.... this whole seasonal change before schedule will continue right into the spring and by Febuary I expect warmer than normal temps and this period could be quite active when it comes to severe weather..but that is still a LONG ways out.

All in all... I think this winter will behave alot like last... with the exception of the dominating upper level lows  and the winter getting an earlier start and end.

Temps

 Precip

Arctic Air Set to Invade The Region

The GFS weather model and its ensemble members have been fairly consistent with a massive dump of arctic air into the region in about a weeks time. The foreign models such as the CMC and the EURO have been struggling with this setup...so I have chosen to side with the GFS.

The GFS has also been consistent with a powerful low pressure system affecting the region....but has still not decided if this will be a northern stream or a sounthern stream solution...and it could very well be a mixture of the two.

Climatology would suggest this would more likely be a northern stream solution but the deeply amplified trough that will allow the rare October Arctic air invasion could suggest a more southern stream solution. If it ended up being the more north scenario then some severe weather would be possible across the state and possible high elevation backdoor snow. If it were more a southern stream scenario then severe wx wouldnt be as likely and valley snow would be possible.... with heavy snow in the mountains.

As much as I would like to side with one of these scenarios...it just wouldnt be real wise to do so just yet...one thing that does look likely is the widespread killing freeze/frost and some healthy mountain snow with this timeframe. That seems like a sure bet as of now...but valley snow is still a very real possibility with this timeframe...just dont have enough evidence to support a definate answer on that just yet.

Will continue to monitor this situation in the coming days and will keep you posted on data as it comes in on what i'm considering the first actual snow threat to the valley locations.

Toot

Snow Around Halloween?

The signals are starting to suggest that snow could fly sometime around halloween....and im not just talking the higher elevations either. Its still a couple of weeks out but it looks to be lining up for some type of system to effect the region with cold enough air in place.

If it does happen there shouldnt be alot of accumulation due to warm ground temps...it certainly looks as if winter is going to get a very early start this year.

Snow will be flying in the mountains later this week but it could be flying in the lower elevations when it comes  trick or treat time.

I will be working on an updated winter forecast due to some recent signals and will have it ready in the next few days

Cheers
Toot

The Winds Of Change

Good afternoon...big changes are on the way. A rather strong system and its cold front will march into the tennessee valley early next week. Models are in general agreement of this solution but differ on the smaller scale details. I would expect some severe weather with this system allthough mainly just a wind threat.

The coldest air of the season will be behind this cold front with NW flow winds kicking in after the front passes thru. I would bet that there will be some snow showers in the higher elevations with this system and the valley floor might even get lucky enough to see a rouge snowflake falling with this one.

There are still quite a few details to nail down and this has some potential to be quite the weather maker..so I will be posting more about this as we get closer to the weekend.....cheers for now.

Toot

Rainy & Cool With A Major Pattern Change Looming

Well the models have finally setteled on a solution...it looks rainy and cool for the next few days due to the gulf low heading up the east coast and a lakes cutter storm swinging in from the west. Things will cool off after the rain ends as a somewhat cooler airmass is ushered in with lows around 40 and highs around 70..

Now...the more interesting thing is the gfs and its esembles are picking up on a noreaster like system around the middle of Oct that could bring both severe wx and some snowflakes. This was a key time I told you about in the "longer range" blog I did a couple weeks back. Remember?? I told you to watch for some severe weather and some possible snow showers around this timeframe.

This looks to be a major pattern change shaping up and we would enter a more winter like climate.. As it gets closer I will be talking more about this interesting situation unfolding in my next blog...so until then... cheers.

Toot

Model Madness And Somewhat of a Pattern Change

Good afternoon..The weather has been absolutely beautiful as of the last few days... bluebird skies and temps mainly in the high 70's and low 80's with the sun shining on the beautiful fall colors...makes one feel lucky to be alive...but this pattern is going to be changing yet again late next week..there will be a tropical/subtropical system forming and it looks to take a route up the east coast...but thats certainly not for sure yet.

The weather models have really been struggling to workout the details of where this system is going to form and track...it's still possible it forms in the gulf of mexico. If that were to happen we would get alot more rain from this system than if it were to track up the east coast. There also looks to be another system and it's associated cold front tracking in from the west. These two systems may congeal into one and usher in some colder air..it certainly looks to cool down...but still not sure on how cold it will get and how this interesting situation will play out and neither are the models.

Im a bit hesitant to go any further until these models workout this situation...but I expect they will workout the details by the first of next week. Until then enjoy this spectacular fall weather we are having :)

Toot

Tropical season could go out with a bang!!

October is already a historically active month for tropical systems on the east coast ...but this big dome of high pressure that is starting to dominate most of the eastern US just adds more spin and energy to an already cyclonically conducive atmosphere that is the Caribbean and Bahamas.

If you take a look at climatology for this region
you will see that October can be a very active month
for tropical systems when it comes
to the Caribbean...Bahamas..and the East coast

The strong canadian high pressure system has surpressed all the convective energy to the tropical regions of the Bahamas and Caribbean and now models are starting to pick up on this and are suggesting there could be a tropical threat to the SE united states in the form of a Tropical/Subtropical storm or Hurricane.

While this is not out of the norm for this time of year...I am considering this threat to be an abnormally high one and interests along the east coast and down in the island regions should keep this in mind. There has been a high number of powerful landfalling hurricanes during this time of year when looking back in hurricane history in this region...and the middle of this month could provide another for the SE US.

Nothing written in stone yet... but the threat is quite obvious to me and the waters down there are still VERY warm and could provide a large amount of fuel to a tropical cyclone if one were to form in this region. Not only that.... but the pattern has becom supportive of a possible landfall somewhere in the eastern US.

Slight warmup on the way and a pattern discussion

If you are needing some nicer weather to get some last minute outdoor work done before the winter..never fear you will get your wish. An upper ridge will take hold on the eastern US later next week and should provide some warmer temps and beautifull bluebird days before the next unsettled cycle swings through.

High temps are looking like upper 70's to near 80 in the southern valley locations....If you dont like the warmer weather... just know that this is part of the grand plan to build a blocking pattern up near greenland...and this blocking pattern will be responsible for blocking the cold air from exiting Canada to the east... and in turn will have to take a path to the south right through our backyards to get around the big block.

You can already see this shaping up if you look at the longrange upper air pattern... the ridging is starting to get more and more pronounced up there... what this will do is start to form a massive troff over the eastern half of the CONUS. At first it wont really be that amplified and you might call it a zonal flow pattern but make no mistake about it...it will amplify by late fall.

Right now we have a pattern simular to this image
and this is called an Omega block...this is were there
are troffs on both coasts of the US
and a big tall ridge near the central US

This pattern will shift eastward
and put us under the warmer ridge

By late fall this pattern will shift more eastward
 in response to higher pressures out west and near
Greenland