December 21st-24th, 2022 | Plains/MW/GL/OV Winter Storm

[Pros3lyte]

14 minutes ago, easton229 said:

Yup 5-8 through those areas 

Thanks!

[Jpfalcon]

7 minutes ago, ncinthenext3 said:

Wow..  DTX with the warning prior to CLE.  Interesting.  I look forward to reading the AFD.  

Little off-topic but our trash pickup is usually Friday, but they're moving it up a day and closing the landfill on Friday due to the winds.

[RobB]

1 minute ago, SOMOSnow said:

@RobB etc, can you help me out here? I haven't used plumes much in awhile. Sref mean for 15z was 2.2 at 10:1 for Springfield. So what is up with this? Shows the average here at almost 5 inches. Are the plumes kuchera? 

IIRC, I believe the plumes include a snow ratio algorithm.  @StLweatherjunkie may be able to verify.  Not 10:1 ratios.  Again, I may be wrong.

[Hiramite]

1 minute ago, SOMOSnow said:

@RobB etc, can you help me out here? I haven't used plumes much in awhile. Sref mean for 15z was 2.2 at 10:1 for Springfield. So what is up with this? Shows the average here at almost 5 inches. Are the plumes kuchera? 

@RobB I'm gonna butt in again. 🙂

SOMOsnow, see my response above to Central Illinois.

The SREF plumes use their own formula, similar to Kuchera.  While in the SREF Plumes, hold your cursor on the Total Snow button to get the pop-up window.

 

[SOMOSnow]

2 minutes ago, RobB said:

IIRC, I believe the plumes include a snow ratio algorithm.  @StLweatherjunkie may be able to verify.  Not 10:1 ratios.  Again, I may be wrong.

Did you see the totals on those ?

[Hiramite]

My phone says I've just been placed under a WSWarning...

Edit to add, the tier of counties south of me still under a Watch.

 

Edited December 21, 2022 by Hiramite

[RobB]

1 minute ago, Hiramite said:

@RobB I'm gonna butt in again. 🙂

SOMOsnow, see my response above to Central Illinois.

The SREF plumes use their own formula, similar to Kuchera.  While in the SREF Plumes, hold your cursor on the Total Snow button to get the pop-up window.

 

That's fine and dandy.  I replied that I believed this was the case.  Glad it is verified 🙂

[snowlover2]

Latest from ILN.

Quote

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
Thursday:

The well-advertised low that will bring snow and an arctic blast to
the area will continue undergoing the initial stages of cyclogenesis
on Thursday. During the morning hours, an upper level PV anomaly
dives into the northern Plains approaching a strong arctic cold
front stretching from the upper Great Lakes southwest toward the
southern Plains. A surface wave along the arctic boundary starts to
become more discernible late morning as mutual amplification of the
surface and upper level PV anomalies begins.

The deepening surface low and amplifying upper level PV anomaly
support a surge of relatively high theta e air east of the surface
boundary into the Ohio Valley through the day. Clouds increase and
the chance for light rain develops into the evening. Forecast highs
moderate into the 40s with southerly flow in place.

Thursday night:

Remarkable mutual amplification of the strong surface and upper
level PV anomalies continues overnight and leads to explosive
cyclogenesis over the region. Remarkably, the surface low may deepen
20 hPa in 12 hours overnight. This type of pressure drop is usually
only seen in the strongest east coast bomb cyclones.

While the low rapidly deepens, winds increase across the region due
to a strengthening pressure gradient. Additionally, the arctic cold
front associated with the low accelerates southeastward into the
Ohio Valley by late Thursday evening. This front will cause a rapid
drop in temperatures from west to east overnight (40s to the single
digits in a matter of hours) and transition rain to snow very
quickly. Any snow that falls in the dropping temperatures will
likely stick relatively easily and could become wind blown. The good
news is moisture may rapidly pull east with the front and lead to an
end to snowfall by daybreak. However, wind chills approach -25 to -
30f by sunrise.

The impacts of the rapidly strengthening cyclone in the vicinity of
the Ohio Valley are expected to be significant:

1) Dangerously cold wind chills approaching -30f are expected late
overnight behind the arctic cold front due to a combination of
temperatures near 0 and wind gusts around 35 mph. A Wind Chill Watch
has been issued to account for dangerously cold wind chills that
could lead to frostbite on exposed skin in as little as 30 minutes.
Please use extreme caution if traveling and have an emergency kit
ready. Also, have a backup plan to stay warm while at home/work in
case of a power loss caused by strong winds.

2) Dangerous travel conditions are increasingly likely due to
accumulating snow resulting in slippery conditions and reduced
visibilities. Visibilities may be further reduced by blowing snow.
Winter Storm Watches and Warnings account for the areas likely to
experience the most difficult travel. A Winter Weather Advisory has
been issued for other areas that will still feel travel impacts, but
may be less severe than the watch/warning areas. Please note,
despite the snowfall forecasts calling for less snow than normally
required for Winter Storm Watch/Warning issuance, impacts may be
significant due to a combination of snow, arctic temperatures, and
strong winds.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Most 12Z guidance suggests that dry air will have pushed into the
area by the start of the period. Some light snow showers may be
lingering in northeast counties, although the GFS continues to
advertise that it may be a bit more robust than that. However,
travel impacts from snow that occurs Thursday night will likely
linger into Friday.

Big issue will be wind and extreme cold. Air temperatures Friday
morning will be in the single digits either side of zero, with a
trend towards even colder temperatures. Any diurnal rebound will be
extremely limited with highs in the single digits above zero. Winds
will be gusting 40 to 55 mph during the day and into the evening
before slowly starting to decrease. This will result in wind chill
in the -20 to -30 range. We have decided to handle the wind chill
separate from the travel/infrastructure impacts from the snow
Thursday night since the hazards from the wind chill will last much
longer. So a separate wind chill watch has been issued into Friday
night. Wind chill, more into the advisory range, will continue
beyond the watch period through Saturday and into Saturday night.

High pressure will build in Sunday and move off to the east on
Monday. There is the potential for a weak disturbance to move
through Monday night, but the chance of precipitation is still low
for now. Southerly flow will occur heading into mid week. This will
result in a warming trend.

 

 

[JayPSU]

1 minute ago, Hiramite said:

@RobB I'm gonna butt in again. 🙂

SOMOsnow, see my response above to Central Illinois.

The SREF plumes use their own formula, similar to Kuchera.  While in the SREF Plumes, hold your cursor on the Total Snow button to get the pop-up window.

 

Also, the spread at his location is quite significant signifying low confidence right now.

[SOMOSnow]

2 minutes ago, Hiramite said:

@RobB I'm gonna butt in again. 🙂

SOMOsnow, see my response above to Central Illinois.

The SREF plumes use their own formula, similar to Kuchera.  While in the SREF Plumes, hold your cursor on the Total Snow button to get the pop-up window.

 

I posted the image of my plumes and mean. Can you look at it? 

[Bradjl2009]

28 minutes ago, snowlover2 said:

Do you or anyone here know why it seems like this afternoon a lot of the models of trended drier once the sqall line enters Pennsylvania from Ohio by chance? 

Edited December 21, 2022 by Bradjl2009

[RobB]

1 minute ago, SOMOSnow said:

Did you see the totals on those ?

I did indeed.  The mean can be a little too high when one sees some explosive members that likely will not happen.

[StLweatherjunkie]

6 minutes ago, RobB said:

IIRC, I believe the plumes include a snow ratio algorithm.  @StLweatherjunkie may be able to verify.  Not 10:1 ratios.  Again, I may be wrong.

You are correct, it's a dynamic algorithm. 

[SOMOSnow]

1 minute ago, RobB said:

I did indeed.  The mean can be a little too high when one sees some explosive members that likely will not happen.

Yes, but big jump up all around from 9z so still love to see that 

[CIWeather]

9 minutes ago, Jpfalcon said:

Little off-topic but our trash pickup is usually Friday, but they're moving it up a day and closing the landfill on Friday due to the winds.

I got a message saying they were moving ours up tomorrow morning.

[RobB]

2 minutes ago, SOMOSnow said:

Yes, but big jump up all around from 9z so still love to see that 

Excellent!  I hope you receive a nice surprise!  Stay safe!

[JayPSU]

1 minute ago, RobB said:

Excellent!  I hope you receive a nice surprise!  Stay safe!

I’m just hoping to squeeze out 3 measly inches.  I think that would look fantastic with the forecasted wind.

[SOMOSnow]

1 minute ago, RobB said:

Excellent!  I hope you receive a nice surprise!  Stay safe!

You also my friend! Thank you !

[easton229]

14 minutes ago, Jpfalcon said:

DTX favoring a more progressive solution which will limit snowfall amounts and duration of excessive winds for SEMI. 2-8" range for their CWA, lowest at the Ohio border (bummer) and highest in the thumb. Get the impression they're leaning more on the short-range models than the globals at this point.

Feels like an event where they start with low totals then up them as it’s going on.

[RobB]

Just now, SOMOSnow said:

You also my friend! Thank you !

You are welcome!

[SOMOSnow]

Almost tripled sref mean at Springfield MO on 15z vs 9z. Got to love seeing that. 

Edited December 21, 2022 by SOMOSnow

[Hiramite]

4 minutes ago, SOMOSnow said:

I posted the image of my plumes and mean. Can you look at it? 

The same thing happened in your Springfield as happened in the other Springfield, lol.

Seriously, go to the bottom right of the plume and find the ALL, ARW and NMB buttons.  Those are the two core groups that make up the a SREF members.  You can click them on/off and see the effect it has on the Mean.  By clicking on the ARW it just shows those members and you can see how high their mean is as compared to the NMB member mean.

[easton229]

DTX’s thoughts 

[cperry29]

18z ICON was meh. Not worth posting lol. This gif reminds me of the ICON…

[SOMOSnow]

6 minutes ago, Hiramite said:

The same thing happened in your Springfield as happened in the other Springfield, lol.

Seriously, go to the bottom right of the plume and find the ALL, ARW and NMB buttons.  Those are the two core groups that make up the a SREF members.  You can click them on/off and see the effect it has on the Mean.  By clicking on the ARW it just shows those members and you can see how high their mean is as compared to the NMB member mean.

Thank you. Glad to see us both jump up either way