1/20/06 - 1/21/06 - MIDWEST SNOWSTORM

[Tim Gonyo]

Latest GFS painting astounding QPF over Southern Wisconsin from this storm:

http://www.nco.ncep.noaa.gov/pmb/nwprod/an...fs_p60_108l.gif

:shock: :shock: :shock:

Comments? rdewey? :lol:

 

[Robert Dewey]

Tim... I thought you said winter was done for the season! :lol:

What I like about this system is no matter how weak the mid and upper level circulation appears to be, there is a very significant amount of vertical motion present along the length of the baroclinic zone, possibly in association with isentropic upglide. This might allow for a rather extended period of very heavy snowfall........ Somewhere.

Models have been flipping around a bit, but I would say anyone from southeast NE... through northern IL and southern WI, into MI are at risk.

I'll probably wait until the short range models capture it before laying down a better forecast foundation.

 

[j_scheerer]

I feel like such a newb for asking this. But what are the chances of Southern Ontario seeing any snow? lol

 

[Alex Lamers]

Finalizing grids and publishing now. Will have products done this evening for my homepage. wiscwx.com as in the avatar if you want my thoughts I'll make sure to write an extended edition AFD

...Alex Lamers...

 

[Robert Dewey]

Right now I'm thinking a track further south than what the 18Z GFS had... All models have shown a southward trend...

While I think the 00Z NAM is too far south, I think the 18Z GFS is too far north. I believe a solution in between the two is most likely at the moment.

 

[Alex Lamers]

Yay my products are out! I got borderline winter storm accums in my grid database for S WI/N IL/E IA part of my forecast area...didn't want to go too robust yet. Looks like it will be an interesting system. Lots of agreement on the global models.

...Alex Lamers...

 

[Alex Lamers]

GFS AND ECMWF HAS BEEN CONSISTENT WITH A TRACK THAT COULD BRING 6 INCHES OR MORE TO SOUTHEAST WI. OTHER MODELS HOWEVER KEEP THE SYSTEM FARTHER SOUTH. IF GFS AND ECMWF CONTINUE WITH GOOD AGREEMENT FOR SNOW OVER SOUTHEAST WI...WINTER STORM WATCHES MAY BE ISSUED ON THU FOR FRIDAY NIGHT/SATURDAY MORNING.

From Milwaukee/Sullivan AFD.

Still looking good! I have a feeling we still might get screwed as usual though.

...Alex Lamers...

 

[Robert Dewey]

Wow... The system is 100% gone on the latest 12Z NAM (or at least VERY far south). Wonder what the GFS will show... Both models weren't looking so hot on the 06Z runs either.

 

[Tim Gonyo]

This one is gone. LOL. Check out the latest NAM.

 

[Robert Dewey]

Looks like the 12Z NAM is the outliar this go around... Again.

All other models still on track... GFS is a touch stronger than the 06Z run. The models that have the best continuity are the UKMET and GEM, both 12Z models showing a decent wave along the baroclinic zone.

I think the 00Z NAM will come around to a similar solution. Then again, all 4 of the other models could swing towards the NAM run - but that's not very likely at this point, though not impossible (I've seen it happen).

Anyway, consulting on one model (especially the NAM which has been a non-performer this winter) probably isn't the wisest way to handle this one.

 

[Tim Gonyo]

But even the GFS has the storm 200 miles south of me.

 

[Jeff Lawson]

The NAM's been kinda useless lately... but, it still demands consideration.

As for the GFS, the last couple of runs have been a little less optimistic. Today's 12Z run (in particular) surprised me... HPC suggests it's an outlier, which seems reasonable. Still, trends would indicate a weaker storm overall.

Honestly, comparing the GFS, UKMET, and ECMWF, I come up empty. The track solutions aren't all that different early on (which is what matters most for me here in Omaha), but clearly diverge with time (more important for those of you in the Midwest/Great Lakes). While most of the models support a solution just far enough south and east to keep me on the northern edge of the best snow, it's been my experience that these southern stream systems come out a little farther north than anticipated. So, I'm prepared for some accumulating snow.

 

[Robert Dewey]

I'm completely throwing out the 12Z/18Z NAM... Hopefully the 00Z NAM will be in line with the other models. As of right now, the 12Z GFS would have the axis of heaviest snow from northern IL through southern lower MI with intense lift and mixing ratios averaging around 4G/KG. The system isn't coming from the deep south, and with a relatively cold profile I would suspect snow ratios of 12-15 to 1 with this storm. 12Z GEM outputting about .75-1.00 storm total QPF's across lower MI.

HPC Day 3 has a HIGH risk for 4 or more inches, MDT risk for 8 or more inches, and a SLGT risk for 12 or more... HPC also has a bullseye of QPF at 1.15 inches near my area.

We shall see...

 

[Tim Gonyo]

Lucky! It's going to be too far South and East for me!

 

[Doug Raflik]

Thats fine with me Tim. We made it this far thru the winter w/out anything major, may as well get thru the rest of it to. With the exception of the needed precip, I would rather just stay brown until march, and have a wetter than avg spring.

Doug Raflik