Non-tropical development part of the Heat Wave's end

At first I wondered how being a believer in the Caribbean could be so wrong. Today the storm system has blossomed into a non-tropical "Nor'easter".  It probably will pass far offshore of the eastern seaboard but we will reap the benefit of winds that become more northerly and NE.  This means ... cooler air!

Here is a satellite water vapor image of the storm.  Note how the deep positively tilted trough to the west of the storm is ventilating it.  The storm is asymmetric with outflow to the NE and is obviously being powered by non-tropical influences. 

Image Source: University of Wiconsin SSEC

As the trough trailing the storm lifts NE we can expect cooler and wet weather next week.  The rain is definitely welcome as well as an end to the heat wave.

Tropical Disturbance in Caribbean is finally making me a believer

Sorry for the delay in posting. 

I definitely wish that the typhoon cold front that freshened and cooled the air Friday and Saturday would have been a little cooler and lasted longer.  Unfortunately the next West Pacific tropical system will likely point to renewed ridging and heat here in the east,

Of more pressing concern is a disturbance in the Caribbean which is finally making me a believer.  The system referred to as Invest 94L by the Tropical Prediction Center has reached a point in its development that it is likely to form into a storm or hurricane.

The adage "go with the flow" applies very well to tropical systems.  When systems track fight upper level flow their tops get blown off and it weakens or dies.  As seen in the water vapor image below THIS system is lining up with a northward bound jet stream and a s a consequence is organizing itself and setting the stage to become Arlene.

Invest 94L Northward movement is lining up with flow from
the deep tropics.  Image Source: Univ of Wisconsin SSEC

The Typhoon Rule signals the coming of cooler weather

I am realizing this week that it is better to be hot and uncomfortable than to be under the repeat threats of tornadoes and severe thunderstorms. Please be in prayer for those suffering in the Midwest and others who are threatened even as I write this article.

Out in the Far East , Typhoon Songda, is providing some hope of a break in the summer heat.  If she follows her predicted path then sometime late Friday or Saturday she will turn east in advance of a trough closing in on Japan.  That would signal the coming of a trough and cooler air to the eastern US either next weekend or early the following week.

Typhoon Songda is forecast to recurve late Friday or Saturday
Image Source: Univ of Wisconsin SSEC

It would not surprise me at all to see out first tropical storm or hurricane of the Atlantic Season in the 6-10 day time frame.  The strong departing heat ridge if it were a summer pattern would have a risk of a tropical system on its SW quadrant. 

Regardless, a break in the worst sustained heat of the entire summer 2011 is coming.

Nightmare storm continues the menace the midwest

The unbelievable storm which has spawned an EF-5 Tornado that destroyed Joplin, MO on Sunday killing 123 people continues to rage in its 3rd day.  So far this year 501 people have lost their lives this year placing the number of deaths at #7 and the year is only half over!  The NOAA estimates that 1,000 tornadoes have occurred so far.  Read more about this horrific season.

A cold pool of air in the upper levels and a huge temperature contrast with the heat that is dominating the east is fueling the storm system which looks like an inland hurricane at times.

East of the menacing swirl are 2 sources of heat that will
dominate through next week. 
Image Source: Univ of Wisconsin SSEC

As of this evening it appears that the storm will weaken Friday as it crosses the Appalachians and leaves its cold upper level support.  Conceptually, I would have a hard time with the idea that the storm could maintain it's strength and organization for that long.  That being said... we need to watch its progression eastward. 

Tomorrow will be a long day west of the mountains as more tornadoes and severe storms threaten lives and property.  Be in prayer for the people who are recovering from the tragic losses and those who are being threatened.

Take tropical notice of what happened today

The little tropical  swirl that has been evident since the weekend took some very significant action today.  While the center of the low level closed circulation plodded westward through the southern Bahamas heat, humidity and convection spread thunderstorms and heavy downpours inland through the Carolinas and parts of VA.

Did you notice the summertime temperature, steamy humidity, low billowing clouds, and downpours which some occurred with virtually no radar warning.  Could this be a foreshadowing of tropical storms this summer?   Had the center of the storm been stronger and therefore "stacked" higher then it would have most likely followed the same flow which was aimed right at us.

The small swirling low pressure has separated
from the tropical plume. 
Image Source: Univ of Wisc SSEC

There is a risk of severe thunderstorm activity tomorrow and more likely Thursday as an approaching cold front collides with the existing heat and humidity.  This is nothing like the once in a lifetime caliber outbreak over a week ago but caution should be exercised nonetheless. 

Storm Formation in the SW Atlantic

No April Fools!  There is a storm system taking shape in the Southwest Atlantic which could acquire some tropical characteristics during the next few days.  WeatherBell Analytics Meteorologist Joe Bastardi has been anticipating this feature for quite some time.  While the storm is interesting it is not expected to play a role in our weather.

National Hurricane Center gives the forming system only a 10% probability
of reaching Subtropical or Tropical storm strength during the next 2 days.

It is important to take notice of the fact that the storm system is forming before the official start of the Atlantic Hurricane Season.  Next week a strong Bermuda High and marginal water temperatures will provide some key ingredients to warm the storm center and give it an opportunity to get a name.

Models seem to agree that the system will weaken and turn SW over the next 3-5 days.  None of them seem to be impressed with the storm's prospects for early notoriety.

URGENT: Tornado Watch as Severe Thunderstorms are now INBOUND

Ladies and gentlemen;

      I have never seen the National Weather Service add the phrase "This is a particularly dangerous situation" to a Tornado Watch.  The storms are now crossing the Triad and should reach Chapel Hill near 1:20-1:30 then cross the whole Triangle during the following 45 minutes.

     What has me really worried is the potential for tornadoes that are stronger and cut paths of destruction.  While twisters are not very common in our region they usually are the weak variety that bounce from location to location striking with 75-90 mph winds.  TODAY storms which do not contain tornadoes will often have winds near 70 mph!

     Please be sure to be in a safe shelter away from windows during the storm passage.  Do not bet your life on being caught driving on the road or out in the open.

    Here is a link to the Raleigh Radar: http://radar.weather.gov/radar.php?rid=rax&product=N0R&overlay=11101111&loop=no

How to recognize that a tornado is coming in NC and VA

Source: Univ of Wisc SSEC

Serious thunderstorms are expected on Saturday Apr 16.  The storm system crossing the midwest is a monster.  The front attached to the system has caused a great deal of damage with damaging wind, hail, and tornadoes.

Jackson, MS was damaged by a tornado which cut quite a path.  This dramatic video shows a large twister in action.

Here in NC and VA tornadoes are rare.  Major ones even moreso.  Most of our twisters have winds less than 100 mph and bounce rather than cut a path.  Unlike other regions of the country tornadoes are difficult to see coming because of heavy rain and the fact that they bounce from location to location.

My three experiences of being near a tornado, one actually seeing a funnel featured distinctive clues which can be useful to you.  If you see the following then run to a tornado safe shelter right away.

• Heavy rain stops suddenly.  Sky might even lighten a bit.
• Hail is hitting the ground/
• Lightning is striking close and often.  

Waiting for the sound of a freight train can be too late because the low hills and trees dampen the sound and prevent the funnel from being seen.  So by the time the tornado is seen it is often on top of the person looking for it.  

Fortunately the major tornadoes that blow out walls, flip cars, and cut a path of damage are rare in NC and VA.  Tomorrow's storms have potential to produce the uncommon twisters.

If a tornado warning is issued or the weather conditions described above indicate that a twister is nearby then take the following steps:

• Go to an interior room , hallway, or bathroom away from windows.
• Avoid temptation to look for the tornadoes.  Broken glass and pieces of toys can become misslies!

Have a safe Saturday!

Concerned about damaging severe weather Friday-Saturday

It has been interesting trying to figure out what form the amplification signal provided by the March 31 and April 1 surge in the SOI.  Finally there is some model agreement on a scenario that I think fits the current climate's tendency for wild weather events.

An intense storm system is expected to deepen over the central Plains and move NE dragging both upper level cold and a strong frontal system through our region. It is bad enough that a cold front is going to ram into unseasonably warm air.  Upper level cold enhances probabilities of hail, damaging wind, and tornadoes.

Here are 2 projections of what could happen in the Friday evening - Saturday time frame:

• GFS - Depicts a deepening system headed to the Great Lakes with a negatively tilted, trailing front which would bring the biggest risk of severe weather to VA and points north.

 

• ECMWF - Storm follows a track just south of the Great Lakes to the NE US.  This scenario has more cold air behind it.
  

We will need to keep an eye on the situation this weekend.  Another update will occur as we get closer to the event.

Spring Bowling Ball ready to strike Central NC-Southern VA

WeatherBell Analytics Meteorologist Joe Bastardi introduced me to a term that best describes a cut-off pool of cold air caught in a low pressure system which is a frequent occurence in Spring, especially during La Nina years.  These systems bring sharply colder temperatures and strong to severe storms as they roll through. Joe calls them "Bowling Balls".

The current bowling ball brought thunderstorms last night then highs in the mid to upper 50's, 20 degrees colder than yesterday.  Now the system is about to hit us from its backside with strong to severe thunderstorms along its warm front!  Take note of the systems comma shape.

Bowling Ball system is cutoff from the jet stream
Source: Univ of Wisconsin SSEC

Thunderstorms early in the evening will feature areas of heavy rain.  Later tonight those in the paths of the frontal storms may see high winds, risk of downpours,hail, and tornadoes.  One storm near Charlotte, NC is showing tornado characteristics.

Current Radar shows the severe thunderstorms in SW NC and areas of moderate to heavy rain/thunder moving through Central NC and Southern VA.  Fortunately Richmond appears to be too deep in the cool pool to get more than rain.  The whole bowling ball is moving SE.

National Weather Service Radar shows storm system
moving SE.  I am concerned about the "tail" on the south and
rear quadrants.  Those areas are experiencing severe weather.

I will send a general alert later this evening if the severe quadrant becomes likely to affect the Triangle/NC or the Richmond area.

Super high SOI signalling dramatic weather ahead?

The Southern Oscillation Index is based on the difference in surface pressure between Darwin, AU and Tahiti related to the tendency up or down.  Negative numbers and/or falling tendency signals a progressive (west to east) weather pattern.  In this case the index soared to 74, the highest I have seen, signaling an amplified (north-south) and often a blocked pattern.  The chart below shows that this occurred on April 1st. 

SOI soars to 74 on April 1st
Data Source: The Long Paddock

Computer models are showing no specific events today here in Central NC and VA on April 14-15.  This is not a surprise as models have been simply terrible through this La Nina episode.  I think that the GFS shows an interesting intense storm in the Plains that would be a headline maker if its true.

April 14 GFS - Very cold airmass dominates the east.
Count the number of sub 1000mb storms on the map!

One clue that the cold air mass affecting the east beginning at the middle of this month has a lot of merit is the strong warming event in the Stratosphere advancing from Siberia to the Pole.  Such an event acts like a plunger pushing arctic air into the middle latitudes.  Unfortunately cold air surging into the the typical gyrations of spring further south is a recipe for severe storms, frosts, and freezes.

Sudden Stratospheric Warming (SSW) advances toward the Pole.
Source: NOAA Climatic Prediction Center

So, interesting days lie ahead.  You can definitely that I will be paying close attention to weather developments and will keep you informed.

Big Weather Weekend for Eastern US

Even though Meteorological Spring runs March-May the season arrived yesterday for everyone else.  Here in Central NC and VA the sun was out, temperatures warm, daffodils blooming beautifully, and the TEMPTATION to get summer garden plants in the ground.

Two weeks ago a high pressure ridge setup in east central Asia which displaced Siberian air into North America.  Fortunately a stubborn heat ridge over Florida will blunt the worst of the cold here in the Southeast but areas north of Fredricksburg, VA are about to get buried in an early spring snowstorm.

Big storm complex is nosing SE.
Source: Univ of Wisconsin SSEC

The first storm will dump snow in the Northeast tomorrow.  The training front is windy and fairly dry but should be watched for severe thunderstorm development as it approaches NC and VA.

This weekend features the MAIN Event as Cold high pressure feeds another storm system and forces it to take a southern route.  How far south will dictate whether the snow line can reach Fredricksburg, VA and even press a bit south.  NC and the southeast will face a threat of severe thunderstorms.

GFS and other models depict deepening storm pushing east,

Following the passage of the storm I am very concerned about a frost threat, even a freeze.  My recommendation is to delay planting of summer vegetables until at least April 10.  The weather pattern is shifting to a warm west and cool stormy east.  It is best to allow the cool period to resolve itself then look at mid April to set possible planting dates.

Timing of late month cold snap just a little later

The appearance of a ridge in East Asia earlier this month was the beginning of a process that will come to fruition by mid next week.   While there is some model debate about how much cold will be delivered and how far south we can expect a period of cooler and stormier weather than we have seen in a while.

Another big development is the return of the negative NAO which dominated during the extraordinary cold period in December and January.  High pressure near NE Canada blocks the eastward progress of weather systems and sends them on a southerly detour.  Notice how the blocking high is expected to develop at the same time that NC and VA will be heating up!  The heat streams northward as part of the High Pressure building process which results in lower pressure, colder temperatures, and potential stormy weather in the places which were most recently warm.

NAO is once again predicted to go negative
Source: NOAA Climatic Prediction Center

I have little doubt that next week will be very exciting in the eastern US.  Stay tuned for details!

Winter 2010-11 Roundup Part 1

For the second winter in a row persistent cold was the story for Central NC and VA.  Who would have ever thought that a La Nina winter with one of the highest 90 day average SOI would be opposite of the historical correlation to US temperatures?

Would you believe that Florida experienced its #10 Coldest winter?
It was supposed to be toasty warm!  Source: NOAA ESRL

Here is how the states ranked in temperature.  Amazingly, only Maine and Utah were above normal!

2009-10 was a strong El Nino and FL hit its record coldest.
This year featured the opposite, strong La Nina.  FL still in top 10 coldest!

Did La Nina impact the east at all?  Pervasive dryness dominated the same regions which were most cold.  A dry winter is expected during a La Nina.

Note the divergence between highest precip (in NW)
and coldest temperature relative to norms in SE.

Finally,  here are some slides showing the dominance of cold in December in the east and a progression toward a more typical La Nina pattern by February. Part 2 will include ideas about what made this past winter unique.  I will also include highlights and lowlights or the season.

East Asia Ridge portends late March Cold

A special thanks to Joe Bastardi  for directing my attention to recent developments in East Asia.  There is a relationship which he taught me years ago called "Cahir's Ridge", high pressure east of the Caspian Sea which pushes Siberian cold over the North Pole into North America.

Admittedly I had gotten a little weather complacent because of our new involvement with the American-Belorussian Relief Organization.  We are blessed to report that $950 has been donated toward the travel and other expenses to a little girl from the Chernobyl affected region to come to our home for 6 weeks of clean food and air, sanctuary from low level contamination, and medical assistance. 

The timing of the high pressure east of the Caspian is a relationship which would deliver the cold air to the eastern US between March 18-22.  Later this week a low pressure system is expected to replace that high, indicating that the cold surge will be short-lived.

Absolutely resist any temptation to plant your summer vegetables until after mid-April at least (Central NC and VA).  There may be a need to protect freeze sensitive lettuce and other spring cool season crops during the incoming cold snap.

Garden 2011 is underway!

In expectation of extremes of weather through the spring and a possible (we need RAIN!) slightly cooler than average summer I have made the following vegetable choices:

• Spring
• Bloomsdale and Galilee Spinach: Both stand up to the heat better than most varieties.  The idea of bringing in a spinach that grows in the mideast is based on my expectation of a rough spring.  Bloomsdale gets planted now, Galilee in a month.
• Bright Lights Swiss Chard:  The leaves and colorful stems are tasty and useful in salads or sauteed like spinach.
• Buttercrunch Lettuce: We really love this lettuce.  Crunchy and sweet.
• Alfresco Blend Salad Greens:  Most people I know rarely eat salad.  It is EASY to grow and when harvest to plate is immediate the taste is unbelievable!  Amazing amount of food for 2-3 square feet of space.
• Jericho Romaine Lettuce:  We have missed the taste and texture of Romaine Lettuce.  I understand that this variety's tolerance of weather conditions reaches Biblical proportions! :>)
• Summer - Seedlings being planted this week.
• Siletz Tomato: Early season F1 Hybrid tomato which does not require bees or other pollination to set fruit.  This variety is intended to provide a tomato harvest in June before the mid and late season maters are ready.  The plant stands up to cool spring weather very well.
• Homestead Tomato: My main all-purpose mid-season tomato.  Last summer we averaged 6-10 tomatoes per day from late June to early August with a peak of 29 in one day!  All from 4 plants.  I have a small garden and the 4 ft height works out really well.  
• Whatever Craig LeHoullier offers:  My limited space forces me to only be able to have a few full-size varieties.  Those of you who have been to Tomatopalooza or followed my pictures and coverage know that Craig's work to preserve the genetic diversity of varieties which span generation is immensely valuable!  Craig is also involved in a global effort to breed new Dwarf Tomato varieties.
• Partenon Squash: This hybrid is expensive but can both stand up to cooler temperatures (May) and set fruit without pollinators.  My plan to beat the squash bugs is to get seedlings going extra-early and use the 3 strongest plants.  Those of us who do not use pesticides have a terrible time growing squash.  I plan to revert to an open-pollinated type in 2012 if spring and early summer look more moderate.
• Indian River Winter Pumpkin - Bug resistant vines produce the most awesome pumpkins we have ever tasted!  We were eating RAW pieces last fall.  I saved seeds after determining that they were heirloom.
• Malabar Spinach:  A completely edible vining plant.  When the Galilee Spinach gives out then this takes over. 
• Armenian Cucumbers:  I wanted to try something different.  Cucumbers always seem to do well in my garden.  These are related to melons and have a milder taste and thin skin. 
• Stevia:  I am going to attempt to grow some stevia.  This mint relative imparts a sweet taste to food and beverages.  Bruised leaves can make a "sugar tea" which can be used with fruit punch or lemonade.
• Others:  Basil, Bush Beans, Nasturtiums (bugs hate this plant.  great addition to salads).  Cayenne, Serrano, and Jalapeno pepper.  GARLIC!!! (Easy to grow!). Maybe a chocolate mint plant or other herbs.

The big theme this year to is overcome a roller-coaster spring and early summer.  If we can experience some decent rainfall this spring then the opportunity exists for a nice summer ...albeit.. with a bad hurricane season.  No west QBO to limit storm growth and keep them out to sea like last year!

Before the warm comes terrible cold and storm!

The buzz about the potential for a east coast winter storm has become a rumble.  After the Dec 26 computer model debacle I have kept a healthy scepticism as La Ninas often feature "phantom snowstorms" in projections. 

Deep snow and terrible cold from Mexico through the Great Lakes was last week's big story.  My friends in Chihuahua, MX received a rare snowfall which covered the roads and temperatures reaching -1 F and a Thursday high of only 23, 42 degrees below the 65 F average high!  New Mexico and South Texas were heavily impacted by similar cold which drained power and natural gas supplies to critical levels requiring rolling blackouts and gas pressure outages.  Imagine temperatures near 0 and no way to heat your home!  Power and gas outages also impacted northern Mexico in a similar fashion.

It appears that Old Man Winter is in a foul mood and is set to target the East with a POTENTIAL monster storm and another serious drainage of Arctic air.  The only good news that can come from such an extreme event is how the high pressure which pushes the dome of cold air into our region often stalls in the south and warms up!  My confidence is very high that the days around Valentine's Day will be warm ... the only threat to 60+ highs being reduced if heavy snow is included with the cold.

One of my key tools which correlates very well to dramatic weather is the daily Southern Oscillation Index (SOI).  In my opinion the 2 day crash to slight negative readings on Jan 26-27 which is both preceded and followed by much higher values is a big warning that the tropics plan to participate in the event. 

Here is a European Model forecast which IF CORRECT would lead to a serious winter storm for the entire east coast.  I have added some notes to the forecast.  As usual, the exact track of the storm means everything.  Whoever ends up in the snow zone will get buried. Local Meteorologist Allan Huffman commented today that extreme projections include a 1-2 foot snowstorm followed by low temperatures near 0.

A ECMWF Perfect Storm

The upcoming week will likely be very busy.  Please expect to have your hopes and fears really stretched by computer models which go back and forth with all kinds of storm and cold projections. 

Will a Raleigh Groundhog see his Shadow?

An early spring is on the line!  Whether the Raleigh Groundhog sees his shadow may depend on the timing of the ceremony.

The massive storm which has buried the midwest in snow and ice is dragging a cold front in our direction.  When the front passes strong winds will sweep clouds away and bathe our potential furry friend in sunlight and delay the end of winter.  Hopefully little groundhog will set his alarm clock early enough to take a nice stroll under gray skies and bring on an early spring.

Source: University of Wisconsin SSEC.

Is the Siberian Express Coming?

Would you believe that there was fresh snow in 49 states today?  Only Florida lacks snow.  Another sign of interesting times?  Raleigh, NC is also on a trajectory that could place this winter in the coldest top 5!

I find it very interesting that some computer model runs are trying to forecast a positive Arctic Oscillation yet have consistently not been negative enough!  For nearly enough the actual results (black line) has been at or below the range of forecasts.

Source: NOAA Climate Prediction Center

The -AO occurs when Upper Level High Pressure dominates the North Pole thereby reversing the Polar Easterlies and displacing the coldest air to the south.  This feature does not guarantee that we on the Eastern Seaboard will get targeted by the cold because a number of other features like this winter's -NAO to route the air southeast.

Similar to 2009-10 warming in the Stratosphere is maintaining Arctic High Pressure and now that feature has gone to further extremes. The 2 small blue areas consistently preceded warming trends by near 2 weeks.  Notice how the warming now has gone all the way to the top:

Source: NOAA Climate Prediction Center

It has been near the top for several days which means that we should be aware that the coldest air so far this winter is coming south.  Projections of NW US High Pressure (called the +PNA) suggest that we in the East are the primary targets!  Mercifully the NAO is slated to be neutral or even slightly positive for the first time since mid November.  Those projections have been accurate throughout this season.  This means that the cold, while serious is likely to lack a mechanism to hold it in place for extended periods.


This Northern Hemisphere projection based on the European Model (ECMWF) depicts a scary scenario which a mountain of High Pressure in Siberia pushes a strong Arctic Vortex into North America.  Off the West Coast that High is slated to build and move inland giving the cold only one direction to go ... Southeast!   On a hopeful note: this kind of pattern is not stable and will not be long lasting.

Of Models and Snow

Yes, there is an opportunity for a Winter Storm (4"+) category snow on Monday and Tuesday.  I will also tell you that the idea of getting buried much deeper than that is also on the table.  Before addressing the storm it is important to gain perspective about computer models.

Models are tools designed to provide possible outcomes from the interaction of known weather and climate variables.  They do not create weather.  As tools computer models actually do not forecast weather, real people do that.  The computer models are also using different algorithms with some performing better in certain situations that others.  Oddly enough the European model, the ECMWF, very accurately forecast the Boxing Day Knockout 3-7 days ahead but lost accuracy once the real system was over land and more data was available.  Other models depend on input of good data to get details about precipitation amounts, system structure, temperatures, and more correct.  The crazy model output leading up to Dec 26 was in my opinion a symptom of poor quality data than model performance.


Therefore let us not cheer model output that looks agreeable.  It is more fulfilling to praise the One who created the great mysterious systems of Weather and Climate which even the world's most powerful supercomputers seem to fall far short in processing.

Job 37:5-6 (ESV)
5 God thunders wondrously with his voice;
he does great things that we cannot comprehend.
6 For to the snow he says, ‘Fall on the earth,’
likewise to the downpour, his mighty downpour.

The Snowstorm

The Jan 10-11 system is not one that conforms to my system of watching tropical patterns to identify systems that will out-perform or a dramatic change in weather.  Oddly enough that particular date follows a period of high amplitude!  While I am not accustomed to winter storms following Fall and Spring rules (tropical peaks and valleys, not just valleys) you need to know that I do not see a big Winter Storm as being guaranteed.

I also expect the weekend to become agonizing as the storm comes onshore and its data gets fed to the tools called Computer Models.  My suspicion is that the same quality problems that plagued days leading up to the Dec 26 storm have not gone away.

On Satellite the storm has some interesting features:

• A large upper level circulation.
• Connection to a powerful subtropical jet stream which is extremely UNCOMMON in La Nina seasons.
• Access to an abundance of moisture.

Below is a water vapor image from the University of Wisconsin SSEC. 

Upper Low attached to Subtropical Jet

The idea is that this system will cross the Northern Gulf of Mexico and join forces with the monster Arctic air mass and associated energy to spawn a storm that exits the US near the NC/SC coast.  If this scenario succeeds then there will be plenty of moisture for lots of snowmaking.  Unlike Dec 26 this storm cooperates with the Northern jet stream but does not phase.  IF this occurs then deep snows will affect a broad area of N GA, SC, and NC.  VA could get some in the south but escape a winter storm criteria.

This ECMWF illustrates the scenario very well.  Sometimes that model has trouble with timing systems emerging from the SW US.  If the system is late then the Arctic cold could push the track further south and leave even Central NC out of the running for a big snowfall.  Here is the possible outcome as depicted by the ECMWF.

A Scenario that would lead to deeper snow totals.

Expect more updates this weekend as the situation develops or fizzles out...