December 29th - 30th Snowstorm

[snowstorm83]

NAM has an initial wave of snow during the day Tuesday but retreats north pretty quickly. Difference is that temps stay below freezing throughout the evening for I-80 folks. I'm thinking this is another GFS thermal fail at least. 

Edit: Looks good for the northern half of Iowa though. I-80 is kind of the riding the ice/snow line it looks. Long range NAM we're talking about though. 

[The Snowman]

I do not envy the folks at the NWS or WPC in the slightest at this moment

[gabel23]

Might be the earliest I seen Hastings put something out.... then consider the uncertainty with the models. I would take it though and run! 
 

https://www.weather.gov/media/gid/sitreport/SitReport1.pdf

[The Snowman]

NWS Omaha

Quote

Models continue to show a potentially significant system arriving
to the area Monday night through Wednesday, with slight
differences in placement of the primary axis of precipitation in
our area. The primary variable so far with this system continues
to be the lower-level temperature fields, with the GFS continuing
to be the warmest (and most progressive) solution, while the NAM,
ECMWF, and CMC being in general agreement with a cooler setup.
This colder blend of solutions continues to be the primary
forecast guidance that we have hedged closer to due to the better
agreement. Ensemble guidance does show quite a bit of wiggle room
in terms of the rain/snow/mix line, so much will be remaining to
be seen as far as the specifics go. With that being said, ensemble
solutions continue to show an axis of significant snowfall at
somewhere in northeast Nebraska into western Iowa, the placement
will continue to shift as we get closer to the event. WPC snowfall
probabilities show snowfall of 8 inches or more being greater
than 50 percent for northeastern Nebraska into western Iowa.

 

[Minny_Weather]

FGF with another clutch 3 sentence AFD!

[jcwxguy]

18z gfs remains north

[snowstorm83]

24 minutes ago, gabel23 said:

Might be the earliest I seen Hastings put something out.... then consider the uncertainty with the models. I would take it though and run! 
 

https://www.weather.gov/media/gid/sitreport/SitReport1.pdf

Nothing from OAX so far but looking at the state view on the GID it looks like 6-8" along and north of I-80 for the OAX region. Pretty bold since Euro is down to 7-10" and GFS is rain. 

[GDR]

Gfs looks north some more

[Niko]

1 hour ago, jaster220 said:

That'd break the matrix..

Interesting!

[bud2380]

GFSv16 has that secondary low dropping huge snow totals across MO IA and others again. 

[Niko]

This looks like an old-fashion GOM track.

[tStacsh]

So much spread 3 days out 

[Tom]

This looks interesting...Gulf Low in the works???

[Tom]

18z GEFS...

[Clinton]

9 minutes ago, Tom said:

18z GEFS...

The good old Kansas City to Chicago dry slot so fitting for this year.

[GDR]

[whatitdo]

From grand rapids NWS office: bolded explains why this is so uncertain

 

-- A range of impacts possible with a messy system Wed-Fri --

We are looking at an extended period of unsettled weather from Wednesday through Friday, with a good deal of uncertainty with regard to details at this time.
 

There is good agreement amongst the models and their ensembles that a fairly strong low will be taking shape to our SW as the southern and northern branches of the jet stream phase over the Plains. It looks likely that we will see a burst of some snow late Tuesday night and Wednesday morning as the warm front moves through. Then, we will see additional precipitation ahead of the system move in later on Wednesday and Wednesday night. This looks like it could transition through a wintry mix before changing all to rain as enough warm air moves overhead. The exact timing of this is still in question. The uncertainty begins on Thursday once the initial low and precipitation moves through.

The uncertainty exists as a result of the eastern progress of the front, and additional energy that will eventually ride up along the front. The final answer will be the result of multiple pieces of upper energy that eventually dictate the formation of the low, and the movement of the parts of it. There is no way at this time to pin down the details for Thursday and Friday with multiple pieces of energy, that are all over the Pacific Ocean and Arctic, that will all interact with each other. The general possibilities are that we could end up on the front side of the system, and have quite a bit more rain and develop some hydro issues. If the system is more progressive east, but close enough to affect us, we could see some accumulating snow. We could even end up out of the main precipitation. Wind also could be a factor.

It is something that bears watching, as different significant impacts will be possible with this energetic system.

[bud2380]

18z Euro. No shift south.

 

 

[GDR]

Time to throw in the towel for I 80 S.

[OmahaSnowFan]

I already have heavy snow wording in the grids for Tuesday.

[CentralNebWeather]

Now they’ve taken out snow accumulation from our forecast and replaced it with rain/snow/freezing rain with 0.50-0.75” of precipitation. Just unbelievable. 

[bud2380]

12z parallel euro

[snowstorm83]

21 minutes ago, OmahaSnowFan said:

I already have heavy snow wording in the grids for Tuesday.

I saw that. Also no mention of rain or ice in the grids. 

[Clinton]

18z Euro Control looks just like the GFS v16.  I will post maps shortly.

[Clinton]

18z Euro control at hr144

[jcwxguy]

7 minutes ago, Clinton said:

18z Euro Control looks just like the GFS v16.  I will post maps shortly.

Alot different for nebraska folks

 

[Clinton]

18z Euro Mean and ensembles.  Remember only goes 144 hrs.

[centralweather44]

3 minutes ago, jcwxguy said:

Alot different for nebraska folks

 

And a nice dry slot over southeast Nebraska. Seems about right and how the last 4-5 big storms forecasted for here have went. I’ve just about wrote this one off for here. North trend seems to be the way to go. Valley also sounded like they are leaning that way as well. Watching Bill Rector on 10/11 tonight he seems to think NE Nebraska is going to be the hardest hit of the state 

[CentralNebWeather]

3 minutes ago, centralweather44 said:

And a nice dry slot over southeast Nebraska. Seems about right and how the last 4-5 big storms forecasted for here have went. I’ve just about wrote this one off for here. North trend seems to be the way to go. Valley also sounded like they are leaning that way as well. Watching Bill Rector on 10/11 tonight he seems to think NE Nebraska is going to be the hardest hit of the state 

Even if we get some front end snow, rain looks to come up from the south and wash a lot or all of it away. 

[jaster220]

12z Euro sure had a bunch of qpf for SWMI with a 980's SLP riding up into SEMI. Just need more cold air to get more SN vs RN.

 

[bud2380]

I know this is a long range model. But the CFS shows substantial snow depth over eastern Iowa. 

[tStacsh]

I have a gut feeling of a stronger southern low and further south/east solution.  

[GDR]

We can all have a dream at one point,right?

[mlgamer]

I hope we have better clarity in the Dec 28 00z and 12z runs with the energy coming on shore tomorrow evening looks like. Maybe just more model chaos until then.

@Tom or @Clinton may be able to speak to this better, but looking back at the LRC it seemed there was support for the initial northern wave but nothing really for a strong southern wave (roughly Nov 13-15). I dunno...just looking for clues to pass the time...lol

[St Paul Storm]

0z NAM has the low going almost overhead. LOL! Fargo gets his snow too. Looks good. 

[bud2380]

Meanwhile 18z GDPS is so far south it hits northern Missouri with snow. 

[CentralNebWeather]

Not much better than the 18z NAM for my area and places south. 
 

[bud2380]

18z RDPS

[WeatherFanOMA]

1 minute ago, CentralNebWeather said:

Not much better than the 18z NAM for my area and places south. 
 

I'm going with this will be a bust for nebraska.  

[Hawkeye]

NAM has nothing but sleet and freezing rain lifting northeast through the CR/IC area.