rockchalk83

00z GFS Ens snowfall (10:1 ratio) thru 12z Sat

18z GEFS thru 12z Friday. Some huge hits here: 

7 minutes ago, StormChazer said:

Until the Euro hops on, I remain uneasy.

There was a trend toward the GFS in the 12z run. We'll see what 00z looks like. And, the Euro ENS mean does show more moisture in the area vs. the operational run for Thursday. 

EDIT: Multiple Euro ENS members do have big hits for our area. 

3 minutes ago, StormChazer said:

Another strong showing from the 18Z GFS.

I hate this feeling that we could be headed for a let down. But, we're at weather's craps table....so let it ride. 

Time for modeling is over. Nowcasting mode is on. Good luck, everyone! 

I'm sure everyone would check 'YES' here: 

How are we feeling, everyone? This definitely looks like the most impactful winter storm our forum has had in sometime! Have you all chucked the global models and started looking at short-term stuff? 

20 minutes ago, RocketWX said:

Here in Wichita, while I'm confident I'm going to get snow, I can already see how this busts for me locally. Most of our snow, (if not all) appears to come from the first wave and the overrunning event that takes place as the front is moving south. Living just southeast of Wichita, how soon this starts and how quickly this transitions to all snow will be critical in maximizing snow totals. Also, need some luck on where the heavier bands set up. Initially I thought we'd get some additional accumulation from the stronger secondary wave but it appears this largely misses us to the southeast giving ne ok/se ks/sw missouri a good snow. My fear is I get a rather short duration of snow here, and places west of me end up with higher totals because of quicker changeover to all snow, and places south and east of me cash in with the secondary wave. Leaving me in the middle with an underwhelming snow. 12Z Euro shows this and I've seen hints of this in other models as well. Hope not, but I'm preparing myself for it. 

 

That is a really good point on a possible failure mode, at least for us out here.

If there's any consolation, I would say the NAM is too warm in the mid-levels and at the surface. IMO I don't think we're going to have sleet with 925 mb, 850 mb, and 700 mb temps around -5C at 6z Wed. Once the precip starts, it should cool the column sufficently to change us to all snow. And all the models suggest that the precip rapidly expands and intensifies after midnight tomorrow into Wednesday. I think we'll do all right here, but to jack, we need to get under a band that doesn't move. 

It's been 13 months since the last >6" snowfall here. I'm prepared for doom here too, man. But, we do need the moisture. 

12z GFS back to a solid snowstorm for C & S KS, N OK into SW-C MO. 

3 minutes ago, WhiteoutWX said:

^^ Why it's hard to trust the NAM past 48 hours. It's prone to large run to run swings. 

Agreed on the NAM as a whole, but would you say the highest confidence in significant snow impacts is from C KS into C MO? 

Also, saw the models average Kuchera ratios between 14 & 15:1 for this event, do you think that's accurate? 

14 minutes ago, stormdragonwx said:

Ironically the 18Z GFS Snow Depth parameter is going bonkers. Depicts a secondary system moving in over the weekend. This reminds me of the 2010 & 2011 winters when we had back to back systems at the end of January going into February.

The 10:1 and Kuchera parameters are depicting the I-44 corridor getting slammed with nearly two feet in spots if this holds.

The 18z GFS hasn’t run yet. That’s from 12z.

6 minutes ago, StormChazer said:

Only major disagreement I see in the models, at this point, is the debate of an ice storm for DFW.

 

Here are the 10:1 snow ratios for the 3 major models. Other than the Canadian(which the run before looked similar to these), which is toned down some this run, they look strikingly similar.

Euro

 

GFS

Canadian

 

 

Kuchera may be better where the cold air is deepest (eg S KS, WC into C MO, and NW OK). There, SLRs could be 15:1, similar to what we had out here on New Year's Day. 

1 hour ago, Wx 24/7 said:

Anyone else still wondering what happens to totally mess this up?

Admittedly, I am. But here in southern Kansas, what will mess it up is if the high pressure comes in and shoves everything farther south...which has been the trend in the last 24 hours, at least in the deterministic models. The ensembles still hold on to the baroclinic zone farther north, on average. 

@StormChazergot the hookup on Euro maps? I’m out with the wife at a Sam’s Club that doubles as a zoo.

14 minutes ago, andyhb said:

So when do we start the conversation about what would happen if the SSTAs weren't so warm re: excess convection dragging the surface response east?

I had been wondering this same thing for the last couple days. 

Just looking at the models & their ensembles from this morning, it looks like the general theme is for the cold front to stall somewhere in northern or central Oklahoma during the day Tuesday, with precip developing out ahead of an upper air disturbance Tuesday night and continuing into Wednesday. 

If I were to forecast this, I would hedge the front/baroclinic zone and associated precip farther south, due to the dense nature of the colder air. Still though, think this is a good shot for all of us to see some much needed moisture and snowfall, but the bigger story, to me, is the colder air that will come down on the backside of this. Temps will likely be pretty cold for four or five days after the storm passes by. 

Just now, CT Rain said:

Yikes. What a nightmare. 

H7 low track looks ok early on back here but damn.

You have a truly unenviable spot in deciding whether to pull down forecast numbers or not. Oof. 

Just now, CT Rain said:

I don't think a lot of people realize how unusually sensitive this forecast is to fairly small changes in the evolution.

The fact that all of the mesoscale models are way out there and the EPS distribution has grown quite a bit from 0z to 12z is a pretty big red flag.

I'd hedge toward a bigger solution but man there's a lot that's pretty weird about this one.

Generally, how have the meso models done with situations like this in your region? Do you see signs in any of them that this will tick back NW. Watching all of this from Kansas, as there's been nothing worth following out here since the big windstorm on December 15. 

Wagons up from BOX 

9 minutes ago, StormChazer said:

Intense ice storm on the 12Z Canadian.

Last night's Euro backed off on the snow but increased ice outputs(frz rain and sleet) for our area.

This morning and the noon run of the GFS pushes the storm to the north and leaves all of us relatively high and dry.

Would think that unless the baroclinic zone stops, that most of the region would get in on some form of wintry precip. The Canadian has mirrored the Euro to some extent with two waves of precip along a stationary front. 

I'm already living and dying by the models in the NE forum (yes, I'm a degenerate), Euro runs in an hour...let's see what happens. 

3 minutes ago, CoastalWx said:

Reggie has the meso low too.

I wonder how much the above normal SSTs in the NW Atlantic is helping in the latent heat/meso low production process. Gotta think it has something to do with it. 

2 minutes ago, Baroclinic Zone said:

That’s a classic KU on the NAM

What is a KU storm?

The storm system sliding down the Front Range of the Rockies had dumped 12-20" in a narrow band from west central Kansas into northeast Colorado. 

Euro & GFS show the possibility of snow showers in OK tomorrow into Thursday, not much accumulation though. 

Looking farther abroad, the models seem to be honing in on a busy period (anything would be considered "busy" after the winter we've had so far) beginning around next Monday. At least one storm shown on the main 12z model suite. 

Perhaps JoMo or some of the others can elaborate on the broader strokes behind the pattern change, but it looked to me that the MJO gets into phase 8 as the AO trends negative.

The development of a TROWAL feature is where the game will be played in this forecast. There maybe some concerns with the temps initially, but should see things quickly change over once you get into that band on the north side of the low. Where the southeast movement slows and begins an east progression, someone is going to get socked. 

Sure wish this would back up even 150 miles. It's parched out here in southern Kansas and the drought shows no signs of letting up. 

19 minutes ago, KC Storm said:

WWA for 1 to 3 posted here. Currently 6F.

Same here. It is interesting that some of the CAMs (NAMNest, WRF-NSSL namely) bring the snow shield just past the Kansas Turnpike. Also, Dodge City and several sites in SW KS have been seeing snow for a while now and I wonder if that's not some signs of a baroclinic zone developing. 

FWIW, none of the models had this developing.