Old man winter has returned

A well developed southern stream shortwave will merge with a strong spoke of energy from a Upper low diving down out of canada and winter weather will result as a baroclinic zone sets up. A band of precip will develop along and in advance of an arctic cold front and will slide through the state tomorrow and Saturday. Where these two energies meet up will be ever important as to the outcome.

This precip will probably start as rain in most places but will quickly and dynamically change to snow due to strong cold air advection and wet bulbing. Flash like freezes will take place and driving conditions could become hazardous very quickly.

Due to the uncertainties I have just made a probability map and counties in grey have the best shot of seeing an inch or more of snow.

Eastern US Snow Storm threat Feb 11th-14th

Good Morning

After what has been an extremely warm winter things are changing as part of the Polar vortex relocates itself in Southeastern Canada. This feature may combine itself with a couple of other large scale features to produce a Noreaster the weekend before Valentines day. It all depends on where a subtropical jet strean shortwave starts to phase with the polar jet stream and its related vortex. This will set up a baroclinic zone along the east coast and a powerful low pressure system may form and ride up this zone in Miller A fashion.

The GFS has been the most consistant model showing this possibility and this remains the biggest eastern US winter threat of the season. The trend all winter has been for these southern stream shortwaves to cuttoff in the southwestern United States and remain cuttoff... but this shortwave is modeled to continue across the southern part of the conus without getting cuttoff from the polar jet and will likely phase with the northern stream at some point.

At the same time a northern stream wave of energy is moving across the northern tier of the US in tandem with the southern one. This will likely result in the most signifigant snowstorm in the eastern US this season but where the snow falls has yet to be determined. At this time guidance suggests a Gulf low threat and I have a higher than normal confidence level in accumulating snow in the Tennesseee valley.

Nothing written in stone yet but there is certainly a threat of winter weather in the eastern US near Valentines day or a couple of days before...the exact track of the stormcenter will decide who sees the accumulating snow.

My Feb - March Forecast for the SE

As you know...you have heard signs of a colder pattern change coming. I can somewhat agree with that although I think it will be short lived.The NAO/AO are already moderately negative.... I expect our area to end January on a frigid note as a deep trough with accompanied snow drops down into the Southeast. This pattern will be locked in place for at least the first half of Febuary and this will be the coldest around here its been all winter.








With the fading NINA and a pronounced NAO block in the baffin island to greenland location you will get that deep trough here in the united states. With 2-3 winter threats. Enjoy the first half of Febuary because I think the PNA and EPO will start to overwhelm the pattern by Feb 20th.





The old SE ridge will start flexing his muscle then... and that will spring us towards spring weather.






Thats not to say we wont get a bowling ball ULL come rolling out of Texas and produce snow in Late Feb or Early March..but by March the 15th cold winter weather will be all but gone.





Current NAO/AO is heading torwards the tank




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Severe Weather Likely In Late January

Being that there is a substancial warm up coming in about a week or so the chances for severe weather will be higher than normal for this time of year...so I went to looking for something to track and wa la..look what the euro model is showing at Hr 240.

Its still a long ways out but what some models show is definately a severe look with arctic air just pouring down into the western US and moist tropical like air being sucked up into the warm sector in the eastern US. This would cause fireworks where those two airmasses butted heads..not only that but that type of storm could definately flip a pattern completely over.

This storm could possibly bring the change that us winter wx lovers have been looking for since winter began. But there have many things that have fooled us on that particular aspect.

Alberta Clipper Round Two

Snow accumulations will be likely tonight/early morning as an Alberta clipper system will quickly track across the area tonight and producing light snow accumulations. Snow accumulations of a dusting to two inches will be possible.

Clipper To Bring Snow To The TN Valley

This setup is pretty unique being that the current system will continue to pull away and its NW flow off of the lakes will combine with the clipper trying to tap the gulf. This was a very confusing aspect of this timeframe and lead me to believe that this would be a pure NW flow event several days ago..but that is not the case. Anyways it will be interesting to see how this evolves on radar. At any rate I think the plateau area will do extremely well with this one as they will change over very quickly but everybody in east TN looks to get in on the action although places in SE TN may get downsloped pretty badly.

I would think that most of the snow will stick to the roads and ground with the very strong cold advection being modeled. Look for temps to drop like a bat out of hell tomorrow evening making for an exciting night.

Snow will be in the air tomorrow

A vigorous upper level disturbance will swoop thru the region on monday and bring a period of snow to the tennessee valley. I expect the snow to accumulate up to 6 inches in the highest elevations of east TN. The plateau counties and the northern valley could also see an inch or two...while most of the valley could see a dusting but I wouldnt rule out a little more than that due to the expected intensity of some of the snow showers and the long duration of the event. These snow showers will be accompanied by strong NW winds that will usher in the coldest air of the season...Glad to see the prospect of some real winter weather finally