Ok.... after I got over the shock LOL If you look at the finer details you can see why the model showed this solution. Again, this is not a forecast. I am only talking about one model run and that is the 18Z GFS. We need to talk about WHY the model is showing what it's showing. We have no idea this far out if it's right or wrong. Ok, so why is this showing a monster snow storm of crippling proportions for us?
Compare the 12Z GFS vs the 18Z GFS which is what I am going to be doing in this post. To begin with on the 18Z GFS at 102 hours valid Tues evening at 7pm, the low is over Seattle Washington at 1010 MB. 12Z run was weaker at 1013 MB and further north over British Columbia. What this is telling us already is that the PNA ridge is taller (more amplified) vs 12Z and it's also in that sweet spot along the West Coast of North America. The trough is already going to dig more right there on the 18Z run vs 12Z. Once again... it all starts with the Pacific pattern.
By Thurs morning at 7am, 18Z run has a 1062 MB High over Western Montana (12Z was 1063 MB but over West central Montana, which means the high is a tad slower dropping in.) The low is now at 1009 MB west of DFW in Texas S of the Red River. 12Z run was similar in position but the low strength was 1013 MB. HUGE DIFFERENCE! These little changes we are seeing on each run may not seem like much to the human eye, but since our atmosphere is fluid, it is vulnerable to just the smallest changes. That's how meteorology works. The smallest change makes a big difference as to what we see down here at the surface where we live.
By Thurs evening at 7pm, the storm is getting its act together! 1008 MB Low is over Northern MS! 12Z run didn't even have a surface low forming yet. This is damn near like an Apps Runner! No East Coast Nor 'Easter on this run if it were to develop as such. Wow! The low does pop a secondary low but it bombs out up the East side of the Apps and NOT along the East Coast. Major, major differences folks! We get that full phase too and not a partial like the 12Z run. The upper low closes off 6 hours sooner then the 12Z run. I told you this afternoon if it closed off faster then look out! Well there you go!
Timing wise on the 18Z GFS, it is obviously slower since it's a stronger system. Snow begins late afternoon to early evening on Thursday. Could begin as a brief rain or mix Southern counties but it won't kill your snow totals much at all lol This is arctic air coming in so you will changeover very quickly! Snow starts to get heavy after midnight Thurs night. We get hammered all day Friday with the action winding down by late Fri evening or so. After midnight for Eastern counties. That is a long duration event for this area! WOW!
Now of course the snow ratios are going to be really good with this system should the GFS be on to something and not "on something"
I shouldn't even be doing this, but I can't help it! Check out the text data for CVG. EGADS!
Code: Select all
FRI 00Z 23-DEC -3.3 -2.6 1018 93 97 0.09 549 535
FRI 06Z 23-DEC -3.3 -1.9 1009 96 97 0.34 543 536
FRI 12Z 23-DEC -2.9 -2.8 1000 96 97 0.60 535 535
FRI 18Z 23-DEC -2.7 -7.0 995 96 97 0.36 527 531
SAT 00Z 24-DEC -5.5 -11.8 1000 92 98 0.18 528 527
SAT 06Z 24-DEC -8.1 -10.3 1008 88 80 0.03 530 525
Whew!
Take a deep breath Les.
A long way to go but at the same time, this isn't fantasy range either.
EDIT: The above text data shows 1.6" liquid. All snow with the temps in the mid and upper 20s for a good chunk of the event! Excuse my language but holy shit!
