December 12-14th Snow and Rain system

[Guest Snowball]

Nam model has been showing the colder temps with this storm. Last storm nam is the only model that took it way north!

[NEJeremy]

Just had power flash here in Omaha from a lightning strike too! Lots of thunder. Hoping for a surprise yet tomorrow night

[Hawkeye]

Obviously no snow over here, but the nam has upped our rainfall to 3-4 inches.  That may be overdoing it, but models have generally been on the way upward over the last day.

[Geos]

NMM had the snow farther east too.

 

[Guest Snowball]

Hawkeye, with the moisture in KS heading north I can see 2+ inches of rain just tonight! My god if it was just 5 degrees colder!! Lighting like crazy!

[Guest Snowball]

Geos,Tom, what u guys think? Love the input u guys have!

[Jaycee]

Had a power flash at my house too, did not expect this much lightning!

 

Flowers just said that the NAM shows no snow for Omaha and rain all the way out to Grand Island? He said the dry slot kills it off.

[Geos]

Geos,Tom, what u guys think? Love the input u guys have!

 

It seems like the models are picking up on some slightly colder air that will be generated by the storm. I would run with the new data coming in.

[gosaints]

Model mayhem for you guys. NAM versus rgem and gfs so far

[jcwxguy]

lol

[Jaycee]

[Hawkeye]

I figured the 00z nam was overjuiced, but the gfs just came in with 3.5" of rain here as well.  The slower and further east track prediction today has helped up the juice around here.

 

3.5" would be one hell of a rainfall event for mid December.  There can't be too many of them in the records.

[gosaints]

I figured the 00z nam was overjuiced, but the gfs just came in with 3.5" of rain here as well.  The slower and further east track prediction today has helped up the juice around here.

 

3.5" would be one hell of a rainfall event for mid December.  There can't be too many of them in the records.

Ya pretty good jog east. Most of our precip is now defo band

[Geos]

GFS refuses to budge on the warmer solution. I would side with higher resolution models now though.

 

If I remember right from past systems, the GFS has a bit of a warm bias.

 

 

[Jaycee]

GFS refuses to budge on the warmer solution. I would side with higher resolution models now though.

 

 

If I remember right from past systems, the GFS has a bit of a warm bias.

 

 

 

http://www.tropicaltidbits.com/analysis/models/gfs/2015121300/gfs_apcpn_ncus_9.png

 

 

 

Models are everywhere yet, this is crazy. Again, I think someone gets lucky and sees incredible snowfall rates. The rain/lightning right now are unreal, if this was snow this would be the wildest system to hit our area ever since I've lived here. I really hope the NAM is right, though the Hi-Res isn't looking to good.

[Geos]

Hopefully the 4km NAM continues on the same track as the 12km. I has a good start towards its solution.

 

[gabel23]

Valley updated their discussion, they mention how the NAM is coming in colder. They aren't going there just yet........won't know much until tomorrow, will be a wait and see type of situation. One thing is for sure, I wast coming home from a basketball game tonight and witnessed thunder and lightning. Not your usual December storm that's for sure! 

 

.UPDATE...

ISSUED AT 918 PM CST SAT DEC 12 2015

FORECAST IS ON TRACK THIS EVENING AND HAVE ONLY UPDATED FOR MINOR
CHANGES. INTENSE WARM/MOIST ADVECTION HAS BEGUN THIS EVENING WITH
THE 00Z KOAX PWAT OF .83 IN...AND THE UPSTREAM SOUNDING AT KTOP
WAS 1.24 THAT IS WELL ABOVE THE CLIMO NORMS. IN ADDITION...SOUNDINGS
INDICATED MUCAPE OF AROUND 900 J/KG. GIVEN THE INSTABILITY AND
SHEAR IN THIS LAYER THE ONLY THING THAT SEEMS TO BE HOLDING BACK
THE THREAT OF SOME SEVERE IS THE CAPE ROBBING INVERSION AROUND H7.
THE STORMS HAVE HAD SOME SMALL HAIL THOUGH AND THIS THREAT SHOULD
CONT OVER THE NEXT COUPLE OF HOURS. OTHERWISE A FAIRLY STEADY
STREAM OF RAIN SHOULD CONT TO LIFT TO THE NORTH THROUGH THE
AREA...THOUGH THIS MAY DECREASE A BIT LATE TONIGHT AS THE LOW
LEVEL JET WEAKENS AND AND LARGE-SCALE FORCING IS STILL WELL THE
SOUTHWEST. WE HAVE LOWERED OVERNIGHT LOWS IN MOST PLACES TONIGHT
AS IT APPEARS THAT IT WILL BE DIFFICULT FOR THE SURFACE BOUNDARY
TO TRY AND LIFT TO THE NORTHWEST. THIS ALSO LED TO LOWERING HIGHS
A BIT ON SUN AS WELL. SURFACE TEMPERATURES IN THE FAR NORTHWEST
CWA /I.E. WESTERN KNOX...ANTELOPE AND BOONE COUNTIES/ WILL BE
VERY CLOSE TO FREEZING OVERNIGHT. WE WOULD NOT BE SURPRISED IF
SOME OF THESE AREA DROPPED TO 32 OVERNIGHT BUT WITH THE WARM
GROUND TEMPERATURES AND WARM RAIN WE FEEL THAT A THREAT OF ICE
ACCUMULATIONS IS LOW.

NEW 00Z NAM CONTS TO BE MUCH COLDER THAN OTHER MODELS FOR SUN
NIGHT/MON AND THIS WILL CONTD TO BE DISCOUNTED FOR NOW. THE NEW
00Z NAM WAS SLOWER WITH THE UPPER LEVEL SYSTEM THOUGH...AND THIS
MAY NOT BE A BAD TREND BUT WILL NOT MAKE ANY CHANGES TO THOSE
PERIODS WITH THIS FORECAST UPDATE.

[Jaycee]

Worried about the dry slot. Flowers mentioned it, and looks the HRRR is picking up on it. I might be off on the time-frame, so if I'm wrong correct me. However, t would make it 3 for 3 this year on every powerful system that Eastern Nebraska has been in the dry slot every single time.

 

http://rapidrefresh.noaa.gov/HRRR/for_web/hrrr_jet/2015121301/full/cref_sfc_f22.png

[Guest Snowball]

I think the dry slot will be just to the east in western Iowa. But I'm also a wish caster!

[Tom]

I think the dry slot will be just to the east in western Iowa. But I'm also a wish caster!

These ULL features are a modeling nightmare, esp when thermals are marginal.  I think dynamic cooling could play a role with this sysem.  Looks like the precip  in the defo band primarily hits at night which could help out with snow accumulations.

[Geos]

Worried about the dry slot. Flowers mentioned it, and looks the HRRR is picking up on it. I might be off on the time-frame, so if I'm wrong correct me. However, t would make it 3 for 3 this year on every powerful system that Eastern Nebraska has been in the dry slot every single time.

 

 

How is the HRRR doing with temperatures currently? A good way to gauge what will happen is to see what model is the most accurate with the temperature occurring in real time. 

[Grizzcoat]

Too much warm air. And warm ground even if you get cold enough aloft. Wasted storm. Most areas haven't seen sub 32 in 5 days. This system, really never had a shot.

[GDR]

Is the snow falling out in Nebraska?

[Guest Snowball]

No! 38 here in lincoln. Jim flowers is saying the higher resolution models keeps trending colder for tonight. He thinks we could see thundersnow tonight. Local forecast says temps rising tonight. Going to have 3 inches of rain. Imagine 30 degree and that moisture!!

[CentralNebWeather]

No snow here. Hastings is really downplaying it. So frustrated. Went from potentially 5-9 inches now they say 1-3. Too much warm air. Boy there is the theme of this season so far. Hoping for a miracle but losing hope in this storm and now the 2nd storm is going north. Can't win here among many other places.

[NEJeremy]

Our local forecast has 1-2" of rain tonight alone from the deformation band which should normally be all snow, and has raised the temp overnight to a low of 41. We're over an inch of rain already plus whatever we get today. I think we'll see 3+" of moisture.... all rain..... in December

[NH4NU]

Jim Flower's 7am update was interesting. Mentioned that overnight NAM models (12z, hires) came together showing a decent sized deformation band forming right up I-80 corridor including lnk and oma as the storm is able to generate its own cold air right in the middle of large rain core. Talked about importance of timing and if the band sets up between certain timeframes we could see a 4-5 hour period of heavy accumulating snow with the mention of thundersnow. Dry air was showing off to our east in parts of central to west central Iowa. 

 

Link to that video: https://www.facebook.com/JimFlowersKmtvMeteorologist/ 

 

NAM Snowfall: http://wxcaster.com/gis-snow-overlays.php3?STATIONID=OAX 

[Tom]

You'd think that someone would be getting buried with snow seeing this type of water vapor imagery in mid Decebmer, but nope, nature isn't cooperating.  So much tropical influence with this storm system.

 

http://www.goes.noaa.gov/GSSLOOPS/ecwv.html

[gabel23]

You'd think that someone would be getting buried with snow seeing this type of water vapor imagery in mid Decebmer, but nope, nature isn't cooperating.  So much tropical influence with this storm system.

 

http://www.goes.noaa.gov/GSSLOOPS/ecwv.html

We would have been talking snowfall totals being measured in feet if we had any cold air to work with. Just goes to show you how reliable the NAO/AO connections are. We need those D**n things to go negative sometime this winter!

[Tom]

We would have been talking snowfall totals being measured in feet if we had any cold air to work with. Just goes to show you how reliable the NAO/AO connections are. We need those D**n things to go negative sometime this winter!

I agree, the track is nearly perfect for NE and nearly 2-3" of qpf fall in the defo band zone.

 

Latest HRRR is trying to change over rain to snow near LNK around 2:00am.

[clintbeed1993]

I agree, the track is nearly perfect for NE and nearly 2-3" of qpf fall in the defo band zone.

 

Latest HRRR is trying to change over rain to snow near LNK around 2:00am.

 

Looks like that's right on top of me I'm in Hamilton County.  I think I'm in a good spot.  It's 34 degrees out right now and the low is forecasted to be 31.  Should be cold enough for snow I would think.  Really  hoping for a nice surprise.

[Grizzcoat]

Dec 13th--- been in house for 13 years,, sump pump going off. Standing water in places I have only seen a handful of times.

With the above-- peoples basements around here flood. EL NINO SUCKS...

[Geos]

Too bad it couldn't snow at 40°! This storm would be historic for Kansas and Nebraska.

-AO more important than a -NAO in most cases. You have both negative with a +PNA then OKwx will end up with the snow. 

 

The temps are so close, I would really watch your thermometers tonight. It's a nowcast event now.

 

[Geos]

One of these is going to verify, I have a feeling.

 

4km NAM.

 

 

ARW

 

 

NMM

 

12km NAM

 

[NEJeremy]

interesting note from Omaha WFO:

THE PW VALUE ON THE 12Z KOAX SOUNDING SHOULD BE A NEW RECORD FOR
THIS DATE...BUT ALSO FOR ALL OF DECEMBER. IT`S ROUGHLY 338 PERCENT
ABOVE NORMAL.

[CentralNebWeather]

I hope you are right geos but they keep lessening amounts here. Now maybe 1-2 at the most. Too much dry air, not enough cold air, low to far south. Can you see the Nebraska frustration. Perfect setup and this. I believe I have been in a blizzard warning, several winter storm warnings, advisories and watches in the last 6 weeks and little or nothing. Thanks for letting me rant, though I don't feel better.

[Geos]

I hope you are right geos but they keep lessening amounts here. Now maybe 1-2 at the most. Too much dry air, not enough cold air, low to far south. Can you see the Nebraska frustration. Perfect setup and this. I believe I have been in a blizzard warning, several winter storm warnings, advisories and watches in the last 6 weeks and little or nothing. Thanks for letting me rant, though I don't feel better.

 

Go ahead and rant!

Too bad your not southwest KS right now. If that upper level low passes to the northeastward intact, you should see at least enough to warrant the advisory. It will be at night after all.

[james1976]

I really should have put my rain gauge back out for this storm. Last night it was thundering and lightning and the power went out a couple minutes. So weird. We hardly had a t-storm like that during the summer.

[CentralNebWeather]

Thanks geos. Appreciate the kind words. We are not in charge of the weather. it will not always follow computer models or a guy's wishes in central Nebraska.

[Jaycee]

it's going to be up in the air, but someone is going to get absolutely rocked. I think Clint or Gabel will be the winners. Hopefully that defo bad forms over LNK/OMA later.