Possible Winter Weather Jan 20-22?

[Thundersnow]

Just a word of caution (which BNA/OHX is apparently heeding), the GFS does tend to have a "cold bias", and some of the other models don't have it as cold on Sunday.

So, we still need to watch some things unfold.

[Ron_Jarrell]

Yeah I stole this from someone on Easternwx, but it's a great illustration of the teleconnect patterns:

[Thundersnow]

I was just looking at the latest output from the 12z GFS.

The 0-degree line has moved ever slow slightly north for Sunday.  It now stretches across the mid-state... putting us more "on the line."  :?

I imagine this is going to be one of those things where it will be so close that we will watching and speculating up to the day of the event.

So, despite last night and this morning's excitement, this is certainly not set in stone.

[servocrow]

WOW!!  The last time I saw patterns like that was when I was watching Laugh-IN in the 70's!!

(great illustration, though..even if I have to take a dramamine now)

Is there any way to slow it down a bit???

[Ron_Jarrell]

That ridge in the PACNW looks impressive if it builds per GFS. I've seen other runs though that erode the high and reform the Aleutian Low to give us above normal temps after this cold snaps. That ridge is the key to us seeing some winter wx in this part of the U.S.

So let's hope that it continues to build.

[Thundersnow]

It almost reminds me of a backward hook-echo signature (only on a MUCH, MUCH larger scale).  Only here, the cold air "wraps around" the ridge in the northern Pacific.

[servocrow]

OHX 4-7 HWO:

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
534 AM CST WED JAN 17 2007

TNZ005>011-022>034-056>066-075-077>080-093>095-181130-
BEDFORD-BENTON-CANNON-CHEATHAM-CLAY-COFFEE-CUMBERLAND-DAVIDSON-
DEKALB-DICKSON-FENTRESS-GILES-GRUNDY-HICKMAN-HOUSTON-HUMPHREYS-
JACKSON-LAWRENCE-LEWIS-MACON-MARSHALL-MAURY-MONTGOMERY-OVERTON-PERRY-
PICKETT-PUTNAM-ROBERTSON-RUTHERFORD-SMITH-STEWART-SUMNER-TROUSDALE-
VAN BUREN-WARREN-WAYNE-WHITE-WILLIAMSON-WILSON-
534 AM CST WED JAN 17 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A LOW PRESSURE SYSTEM WILL MOVE NORTHEAST FROM THE GULF THIS WEEKEND.
COLD HIGH PRESSURE SITUATED TO THE NORTH COULD PRODUCE SOME WINTER
PRECIPITATION ACROSS MIDDLE TENNESSEE SUNDAY AND MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME.

[snowdog]

Yep 12z op GFS run is doing the cha-cha again.  Actually looks like yesterdays 12z run with the rain/snow line at the KY-TN border.  For some reason, recent history maybe  :evil: , I feel we (in middle-TN) are going to get the ol screw job again on this one.  I would much rather see that rain/snow line around northern Miss-Bama-Ga because it will more than likely migrate north as the event gets closer.  

Will be interesting to see what the 12z GFS ensembles have to say.  They have actually kept the rain/snow line around the southern TN border.

[Thundersnow]

I know what you mean, snowdog.  It's a scenario we're far too familiar with here in Middle TN.

I've noticed an interesting pattern in how these things develop though.  Typically, the long-range/extended will present a very cold, interesting scenario, and then things back off to a warmer solution in the medium range... only to come back to some sort of compromise as we get into the near term.

So, the ground truth ends up being somewhere in the middle... or being something different altogether.

[servocrow]

You guys should go to James Spann's website and view his Xtreme Weather Video (you can get there via the NashvilleWX site or AlabamaWX, I believe).  He gives a pretty good and detailed play-by-play of the coming days.

It's pretty good.

[Thundersnow]

James Spann seems to be pretty highly regarded in Alabama (the Birmingham market).  His forecasts and blogs are frequently discussed on the TalkWeather Southeast weather forum.

[Eric]

Just got through watching James' video.  Very interesting to say ther least.  he said the models have been "busting temperature values by as much as 25 degrees".  According to the models, we were in the warm thicknesses with all this moisture coming in, but if they have been busting the temps by as much as 25 degrees, we could very well be in trouble.  

Makes my liver quiver... :scratch  :?

[snowdog]

Concerning Spann's video.  I like the part where he says the model, temp wise, is junk.  He seems to think the GFS may actually be under predicting the cold (which it has been doing with this current pattern) that will be in place for the Sunday-Monday event.  That woud be great news if he is correct.  

Again, I like the general overall trend for the last half of January.  Very cold temps and an active southern jet.  At some point one of these storms has to end our run of bad winter luck.

[Thundersnow]

The handling of the cold air definitely needs to be kept in mind here.  

The interesting thing is that usually we see the GFS trend things north/northwestward over time.  In its own scheme, it may be doing the appropriate thing of adjusting the gradients northward.

But, if the 0-degree line should really be further south than what the GFS is depicting to begin with, then......

[Reneezelle]

Sure. Uh-huh. Whatever. Yeah right. Okie dokie.


  (Maybe if I be mean and sarcastic to the snow it will come at me with avengence!!  :lol:  :lol:  :lol: )


   I know personally think quickest way to get me to do something is to tell me I cant. So. on that note

 IT CANNOT SNOW THIS WEEKEND. IT DOESN'T KNOW HOW. IT CAN'T SNOW EIGHT INCHES SO I CAN STAY HOME ON TUESDAY. IT CAN'T AND WON'T. THERE WILL NOT BE ENOUGH SNOW TO TAKE MY CUTE ANIMALS OUTSIDE FOR PICTURES. IMPOSSIBLE.