January 21-23 Wintry Mix Transition Event

[Black Hole]

As the next cold airmass begins to retreat model guidance is indicating a potential wintry mix of sleet and freezing rain. It will begin over TX/OK/AR, moving northeast up towards Michigan where the threat of ice will gradually transition to a threat of snow. Here are some maps from the GFS this morning. Other models are similar but obviously with key differences as well.

Heavy rain may follow for the southern Plains:

 

 

 

[Hoosier]

To repeat from the other thread... besides a general freezing rain where temps are below freezing, I'd also watch for ground icing where 2m temps are above freezing as it will likely take the ground time to sufficiently warm up after this intense cold spell.

[Tom]

Well, well, well...look at what we have here...this is the week where we see the extreme cold departing, but the presence of a Cold Canadian HP still hanging around on the northern end of the Sub will produce wintry precip.  Let's add to the Glacier, ay???

0z GFS for early next week...

 

0z GFS..pretty darn similar...

[Tony]

1 hour ago, Tom said:

Well, well, well...look at what we have here...this is the week where we see the extreme cold departing, but the presence of a Cold Canadian HP still hanging around on the northern end of the Sub will produce wintry precip.  Let's add to the Glacier, ay???

0z GFS for early next week...

 

0z GFS..pretty darn similar...

This one could turn out to be interesting and some locales could cash in with some pretty good snow. This system seems fairly weak and with the cold air in place it will be hard for warm air to overtake this HP in place. 

[Tom]

2 minutes ago, Tony said:

This one could turn out to be interesting and some locales could cash in with some pretty good snow. This system seems fairly weak and with the cold air in place it will be hard for warm air to overtake this HP in place. 

Yup, I am mirroring the same thoughts.  As long as the HP can straddle the GL’s it’ll be a good support for a widespread snow event somewhere.

[Hawkeye]

For days, models showed all rain here.  Recent runs have certainly trended colder and snowier.

[Hoosier]

47 minutes ago, Hawkeye said:

For days, models showed all rain here.  Recent runs have certainly trended colder and snowier.

With how this month has gone so far, guarantee this doesn't come south haha

[gimmesnow]

Sorry everyone else but this being snow for me is the difference between parking my snowmobile for the rest of winter (very likely) or spending all of February snowmobiling. Considering I haven't been able to really use it for more than a few days the last few years, and I'm too cheap to buy reg + trail pass to ride 3 days, I haven't really had good snowmobiling around here since before COVID.

Things must be trending cooler. Forecast was almost an inch of rain next week up here, would have ruined the ski hills (they are almost all in rough shape except for Alpine Valley), snowmobile trails, etc. Forecasts are now calling for a little bit of rain, like 1/8th in. Snowmobile trails down here are amazing, probably haven't been this good in 10 years. Alpine Valley was amazing yesterday, best it's been on most of the runs in years. The last week here has actually been a great winter. I just want this system to not end it prematurely and end up hobbling along hoping for snow to fix it. Greedy I know but it's been so long.

Just need to make it through this warmth and hopefully we get back to some cooldowns and we can spread the wealth for some of you who have been neglected.

[Hawkeye]

12z Euro has snow, but it's weakish.

[gimmesnow]

Just as long as the rain stays away from this thaw I will have no complaints.

[CentralNebWeather]

Just saw a forecast of snow and potentially ice Monday night to Tuesday morning with .05-.15” of ice. This will need to be monitored closely. Sure can’t say this has been a boring winter around here since the Christmas blizzard onwards. 

[Black Hole]

Models seem to be zeroing in on the general area and timing but still with a lot of spread for how much ice.

 

Forecast soundings continue to show this to be a very marginal situation with only a small area near the surface that is below freezing and its primarily driven by dry air evaporating moisture given the strong WAA just above the surface. It'll be close, and we will probably get something, but I am betting against a big event. 

 

 

[Grizzcoat]

GFS tonight coming in colde aloftr and more qpf for many-

[Clinton]

GFS tonight coming in a little icy for mby Monday morning, hopefully temps get above freezing quickly. 

[Black Hole]

Models seem to still be trending up if anything for ice amounts here. GFS/ECMWF are near 0.2" here, CMC is higher and NAM is lower. UKMET is also probably lower near 0.1". I'm assuming some relatively inefficient accumulation since temps will be right near 32F. Roads will hopefully be ok given that fact. 

[Black Hole]

GFS is still trending up on its latest runs. It even has temps 28-29F Sunday evening with the first round of precip, cold enough for problems!

[Hoosier]

The overnight ILX afd mentioned that the ground may have more ice than elevated surfaces and trees.  It's often the other way around, but because of the circumstances of transitioning out of some deep cold, it's quite possible.  This is where experience comes into play with forecasting as the models' freezing rain output generally only accounts for precip with air temps at/below freezing and doesn't factor in ground temps.  Also looks like it won't be a rapid rise to well above freezing temps for many areas (i.e. not going from 32 to 40 in a few hours), so the slow climb through the 30s should also slow down the amount of melting on the ground.

[Hoosier]

Posted this at another board... just keep in mind it's geared more toward the IL/IN/MI etc area and not necessarily for areas toward the south as I didn't focus on things there...

The main knock against this setup -- and it's not a trivial one -- is the high pressure slipping off the east coast, which sets up southerly low level flow at the surface.  That is usually not conducive to prolonged/heavy icing as there is nothing to lock in and replenish the cold/dry air.  There is a high that comes in from the north later on, but its main influence will be felt in the northern tier.

That aside, most every other factor is quite favorable.  Precip rates generally look light, perhaps eventually becoming moderate at times for some areas, which will minimize runoff and help with accretion efficiency.  There will be a bit of a breeze, but not too strong which is actually a good thing for ice in this particular situation as it should tend to slow down the northward pace of the WAA compared to having a stronger southerly flow.  And as already mentioned, the prolonged antecedent cold is very favorable for causing problems with ground icing.  The antecedent airmass also looks fairly dry, so it will take a while to get dewpoints above freezing and completely exhaust the wetbulbing process.  

[Hawkeye]

The Euro had been pretty weak, but it is trending toward a few inches of slop.

[Black Hole]

There is now a mix of Winter Weather Advisories and Winter Storm Watches for the area for tonight into Monday morning. There is still a lot of uncertainty with when we warm up tomorrow, but definitely going to get some ice this evening. It'll be an adventure coming into work tonight for my shift. 

Guidance is mostly showing .15 to .30" here, so assuming some runoff maybe .1 to .2" of accretion. 

[Clinton]

Icy conditions expected tomorrow morning and maybe into the afternoon.  I'm concerned about road conditions tomorrow morning given how cold the surface temps are.  WWA in effect for this and a rather significant ice storm looks possible across the Ozarks. 

 

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 9 PM THIS
EVENING TO NOON CST MONDAY...

* WHAT...Mixed precipitation expected. Ice accumulations of up
  to one tenth of an inch.

* WHERE...Portions of east central Kansas and central and west
  central Missouri.

* WHEN...From 9 PM this evening to noon CST Monday.

* IMPACTS...Plan on slippery road conditions. The hazardous
  conditions could impact the morning commute.

 

[Clinton]

6z GFS 

 

[Niko]

Looks like another couple of inches for mby coming up tomorrow nite and into Tuesday, b4 some ice starts mixes in. I wonder how how long that warm air can be delayed b4 reaching the northern burbs of Detroit. Also, not a fan of ice. Hopefully, it can stay all snow after getting a couple of inches of snow and end as a little freezing drizzle or sleet and call it a day.

[Hoosier]

18z HRRR has a good 12-15 hours of freezing rain around here.  

Still some uncertainty on just when temps will warm above freezing.

[Hoosier]

LOT issues advisory for everybody.

Tuesday morning driving could be a trainwreck, especially on untreated surfaces.  Also gotta be careful just walking to your car or whatever.

[Minny_Weather]

Pretty insane there's a chance for ZR up here this evening and tonight with temps in the teens.

Flurries falling currently. 19*F.

[Hoosier]

Will be curious to see what kind of ice that downtown Chicago can pull off.  Obviously have 2 big factors to always consider there, one being the urban heat island effect and the other being lake temps if wind is onshore.  In this case, the wind is largely offshore, which will tend to negate the lake impact (nearshore water temps have cooled a fair amount recently anyway).  So that leaves the heat island question.  That area did get a decent icing event a few years back, so it can happen when the setup is right.

[tStacsh]

2 minutes ago, Hoosier said:

Will be curious to see what kind of ice that downtown Chicago can pull off.  Obviously have 2 big factors to always consider there, one being the urban heat island effect and the other being lake temps if wind is onshore.  In this case, the wind is largely offshore, which will tend to negate the lake impact (nearshore water temps have cooled a fair amount recently anyway).  So that leaves the heat island question.  That area did get a decent icing event a few years back, so it can happen when the setup is right.

It’s the side roads that are still snow covered.  They are going to a disaster here.  Even will just plain rain for the second storm.  

[Andie]

41* and cold rain on the doorstep. 

[Iceresistance]

10 minutes ago, Andie said:

41* and cold rain on the doorstep. 

I am in the Ice, already a Glaze. It was mixing with snow earlier

[OKwx2k4]

Well, this has escalated from "Not much to worry about", to ice storm warning pretty quickly. I think going in all the caveats and uncertainty was well-covered by NWS and I'm very okay with that. 

Ice events and cold-pockets over terrain are hard to measure. I wouldn't have guessed missing the high by 3 degrees today, either, based on conditions/modeling. Must be a lot of snow still laid up in the valleys and hollers out here. 

Another unique thing about this event is that it may be the most destructive in such a short span for any ice storm I've witnessed in my lifetime. A half inch of ice and 30 mph gusts for 12 hours is bad news. 

[OKwx2k4]

2 hours ago, tStacsh said:

It’s the side roads that are still snow covered.  They are going to a disaster here.  Even will just plain rain for the second storm.  

Here in OK, I still have snow covered side roads that never see sun due to trees and I said the same thing. 

There's going to be nothing I can do in any precip events until the ground thaws as its uphill every way out of where I live. 

[tStacsh]

20 minutes ago, OKwx2k4 said:

Here in OK, I still have snow covered side roads that never see sun due to trees and I said the same thing. 

There's going to be nothing I can do in any precip events until the ground thaws as its uphill every way out of where I live. 

My English was so bad in my post lol.  Been watching and celebrating the Lions victory.   Good time to be a Wolverine and a Lion fan.  

[OKwx2k4]

4 minutes ago, tStacsh said:

My English was so bad in my post lol.  Been watching and celebrating the Lions victory.   Good time to be a Wolverine and a Lion fan.  

Yes it is. ( not your English, a good time to be a fan). I hate that they beat out Baker, being a red-blooded sooner alum, but good stuff no less.

But, absolutely so happy for you all up there! Pretty cool.

[tStacsh]

5 minutes ago, OKwx2k4 said:

Yes it is. ( not your English, a good time to be a fan). I hate that they beat out Baker, being a red-blooded sooner alum, but good stuff no less.

But, absolutely so happy for you all up there! Pretty cool.

Baker played a great game.  Until the last throw.  That was a good game.  I like him for going into Ohio State and beating them and planting the flag. 

[OKwx2k4]

1 hour ago, tStacsh said:

Baker played a great game.  Until the last throw.  That was a good game.  I like him for going into Ohio State and beating them and planting the flag. 

Yes. Was telling my brother, he reminds me so much of Brett Favre, then he did that. Lol. Said, "Well, that too. He has Favre's problem of trying too hard."

Ohio State...That's a moment that belongs enshrined in sports history forever. It was electric, even from home. It was like he broke them. Lol. Too cool. 

[Hoosier]

Large differences between the NAM and HRRR in terms of ice.

[Black Hole]

It's been icing off and on all night. It's outrageously slippery in my parking lot at work. Took several minutes to go like 100 feet. Pretty good amount of moisture moving in the next few hours, we will see how well it can accrete. There isn't much evaporative cooling potential left at this point. 

I'd estimate about 0.1" so far, probably going to get about that much more by daybreak assuming a healthy amount of run off. 

[Black Hole]

Measured 0.2" of ice just now, and it seems to be winding down. It will all be melting off within a couple hours. A short but fun little event. 

[Andie]

High of 38 today.  100% rain chances. 
Much needed.
 I’m so glad this came in as rain this week. DFW was just south of the freeze line last night.