• Hello, please take a minute to check out our awesome content, contributed by the wonderful members of our community. We hope you'll add your own thoughts and opinions by making a free account!

Wintry January 3rd-6th, 2018 Winter Storm The ARCC/Xtreme Weather Special

Storm5 said:
Gfs has the second wave that the euro and cmc have but it’s a late bloomer
2b100abfd9c1f89da7fcd4b7c3702100.jpg



Sent from my iPhone using Tapatalk
Click to expand...
Honestly I think that have the potential to start trending toward the NW!!!
 
I did read on another forum some modeling and observations particularly discussing the 18z and 6z runs of GFS and accuracy, basically it read out like this that verification wise 06z and 18z performed it's worst during 120-90 hours range and generally performed its best on verification within 3 days... so historically perhaps this is a time it would be in it's least accurate window for the systems
 
Spann:
NEW YEAR'S EVE FORECAST UPDATE: Another challenging forecast for Alabama ahead; both major global models now paint potential for some light snow over North Alabama Sunday and Sunday night (New Year's Eve). Unfortunately a monstrous 1050 mb high over the Central U.S. will feed in very cold air, potentially dropping us into the teens late Sunday night.

As learned from "Snowmageddon" in January 2014, the ice accretion process is much different on roads when temperatures are in the teens and 20s. So, even light snow can produce high impact in very cold weather.

At this point it is simply too early for a specific forecast. It could very well turn out to be mostly cold and dry, or we could have dangerous driving due to snow accumulation. It can go either way. But, we are simply raising the flag to let travelers know of the potential, and keep an eye on our forecast discussions in coming days as we get closer to the weekend.
 
Yeah the 18z isn't a good run but I'd wait until the 0z and see if it bounces back before declaring anything.
 
Every thing was trending better until 18 GFS! Wait on tonight's run before going off the cliff
 
RollTide18 said:
I wouldn't call one model run a trend.
Click to expand...
I agree with your statement. However in this case with the gfs the trend is very clear over the last 4 cycles towards a much weaker solution vs what it’s previous runs showed . We want to root for an H5 look like the 18z nam has with a shortwave that’s further south into the west coast and more stream separation. A light event for many looks good around New Years still many ways to screw it up though . So we get to wait and watch.
 
I agree with Charlie, models are showing a system, thats better than nothing.
 
Meteorologist1999 said:
Thank YOU People sometimes confuse me a Trend is more than ONE!!
Click to expand...

A trend would be stringing the energy out, which is what we are starting to see with the shearing of the wave via various modeling. The biggest trend for the last day though, is that most modeling now have the energy, which was a fold to the GFS & NAM solutions.

So now, the idea is to look for a trend in the shearing of the wave. How much does the Northern Stream dominate it? I would guess, a lot. We aren't far out from the moving parts that will decide if our wave dives in, more compact, and stronger, or if it's going to get stretched out.
 
To go with the above; for the model watchers. Look for more separation of our potential energy, look for more amplification of it, and look for a sharper trough. Which all goes together. If you guys look at the Canadian, go ahead past the New Years wave in question and notice the energy behind it, how it dives down, and starts bringing the flow from the SW into GA & the Carolinas (before snowfall begins). That is what you kind of want the New Years wave to do, but a bit earlier to get everyone involved.


gem_z500_vort_us_27.png
 
From NWS Huntsville for Sunday:
highs will have a hard time even climbing into the
upper 20s to lower 30s. This in fact may be generous. Either way,
newest ECMWF develops between .1 and .2 inches of precipitation, as
the surface cold front swings through the area through Sunday night.
This is more in line with GFS, which has consistently been the wetter
solution for this system. This precipitation will all be in the form
of snowfall. At this point, since not all model guidance is going
with the wetter solution, not going the full QPF that GFS or ECMWF
are forecasting. However, there is increasing confidence that there
will be a period of light to possibly moderate snowfall Sunday into
Sunday night. This could at least produce up to 1 inch of snowfall
across much of northern Alabama and portions of southern middle
Tennessee. There could be as much as 1 to 4 inches with this system,
if higher QPF amounts turn out to be correct.
 
Last edited:
Storm5 said:
I agree with your statement. However in this case with the gfs the trend is very clear over the last 4 cycles towards a much weaker solution vs what it’s previous runs showed . We want to root for an H5 look like the 18z nam has with a shortwave that’s further south into the west coast and more stream separation. A light event for many looks good around New Years still many ways to screw it up though . So we get to wait and watch.
Click to expand...

No doubt, it's not the super juicy run of a few days ago but most models have at least depicted a light event. Apparently a NW trend may not happen due to the NS being too dominant so we have to at least hope it holds serve in futute runs, the Euro actually showing a storm is a good sign though.
 
I think one of the problems we are running into around new years is the closed ridge over southern California and the big vortex in Canada and the NE the combination of the 2 is creating a steep height gradient and the waves are being channeled and sheared. The gfs had a healthy wave over the PNW at 66 hr but it shears over the Rockies and the vorticity is absorbed into the larger vortex. We could easily score a big storm if that height field relaxes or a wave stays intact enough to survive into the region. The 3rd wave that 1300m alluded to around 1/3 has the best chance as the ridge out west is taller and shifted west and the vortex starts to lift a bit. If you wanted to get really into dream scenarios the energy over Texas at 138 could get left behind and phase with the incoming wave and we are digging out for days

Sent from my SM-G955U using Tapatalk
 
You must log in or register to reply here.
Back
Top