Ice Ice Baby December 28-29 Storm Discussion

[Typhoon Tip]

4 aspects go against anything of consequence... 

 -- system movement too fast.  6 hours and the QPF's done reporting

-- not enough in situ +PP over Ontario/QUE already dammed into the region. 

-- related to that ... cold is not being actively supplied with sub 0C DPs undercutting; without that thermodynamic fix, latent heat of phase change will self-defeat the situation

-- not enough QPF 

This is a road skidder and a couple submissions to funniest home videos type ordeal ...  

I do agree though that with initial cold in the Ekman BL drag working with speed of system translation, the whole thing should probably be done with and on the west side of the escaping lp before warm sector makes very far N. 

[Sey-Mour Snow]

15 minutes ago, ORH_wxman said:

I dunno, I really think it depends how long temps are above 40F…in your area to my area, there’s a decent chance it wipes the pack. Prob gonna be 12+ hours of 40+ dews.
 

Not a lot of water in the pack either (though my bottom layer from 12/23 is kind of dense). Western CT up into ORH county might keep it though as they spend less time above 40F. If we had like an inch of water in the pack then this wouldn’t wipe it out, but this is not that type of pack. 

Pack here is very dense. Around .7-.8” water in it. As you said guidance some keeps western ct around 40 max, some 44-48 max.. 

other factors it’s a cold pack, have to raise the temp first to melt it. Also we may get a decent glaze in some areas which will protect it for a few hours. And hopefully minimal warm rain. 

[Modfan2]

Currently 8F off a low of 3F in E CT, surrounding hills were about 10 degrees warmer…Wondering if models factoring in the current cold air in the SNE valleys and does all of this just get warmed during the day?

[HoarfrostHubb]

5” of fluff will be decimated, even with the cold rain.     Swiss cheese incoming

[ineedsnow]

2 minutes ago, HoarfrostHubb said:

5” of fluff will be decimated, even with the cold rain.     Swiss cheese incoming

Doubt it if we get a layer of ice on top.. plus still had some snow from before that's not as fluffy

[ORH_wxman]

2 minutes ago, Sey-Mour Snow said:

Pack here is very dense. Around .7-.8” water in it. As you said guidance some keeps western ct around 40 max, some 44-48 max.. 

other factors it’s a cold pack, have to raise the temp first to melt it. Also we may get a decent glaze in some areas which will protect it for a few hours. And hopefully minimal warm rain. 

This tends to work better when the pack is deep and higher water content. It takes time to heat water…this type of pack prob gets pretty ripe quite quickly once dews reach 38-40F. 
 

You're area got a nicer dose of QPF so the valleys there could be tough to wipe out. 

[Damage In Tolland]

Models always warm too quickly in these setups. If it can stay below 40 until noon, might be ok . 

[dendrite]

6 minutes ago, Damage In Tolland said:

Models always warm too quickly in these setups. If it can stay below 40 until noon, might be ok . 

Maybe one of those setups where you shoot up to 40° while Ryan is still -ZR in WeHa?

[Typhoon Tip]

1 hour ago, Modfan2 said:

Currently 8F off a low of 3F in E CT, surrounding hills were about 10 degrees warmer…Wondering if models factoring in the current cold air in the SNE valleys and does all of this just get warmed during the day?

No need to...  

the cold you are referring is particularly low level, and not substantive in the mass loading into this system's preceding environment.  The "real" synoptic cold is still low ... 22-ish with DPs of 10 or so, but with such limited +PP ( positive pressure pattern (high pressure) ) situated N, a 20 to 25 kt sustained 925 mb low arriving flow will change the setting very quickly.   

These metrical limitations on this system are not going anywhere.   They are a predicament/detriment to this system's ability to maintain froze or freezing profiles.    

Lemme tell you something ... in late January 1994, we awoke one faithful morning to Winter Weather Advisory headlines in place, a temperature of 9 F on the weather lab's tele, and periodic flurries/grits coming down in the dim blue light of dawn throughout the Merrimack Valley.  Deep winter was in place.   By noon, sleet pellets had broken out, there was a south breeze, and the temperature had risen to 23 or so...  By 3 pm, it was 31 F with steady freezing rain.  By 6pm, it was 53 F with wildly swaying tree tops, and ice fog rolling off the snow pack and piles.  By 9pm, it was 61 F with 55 mph gusts. Student around the campus had spilled into the commons and down town streets of Lowell's pubs, in short sleeve shirts that seemed to finalize a defiant mockery of winter...  

9 to 61, in 12 hours.   

All because a cutter went through BUF-ish, and had no antecedent +PP to protect from the arriving WCB ( warm conveyor belt ) -related wind field.  

Now, this situation doesn't have a 65 kt 920 mb jet core fire hosing at it...no.  But, the 40 kts with no leading surface high is going to still reverse the tables and do it probably at a speed that comes to some surprise to people, even in the valleys.  

[wxeyeNH]

Tip, yesterday, Dandy was also not very impressed for even up here.  What am I missing?   1.25" of liquid, temperatures in the mid to upper 20s rising to around 32F tomorrow afternoon.  Longer precipitation time up here too.  Weather bell clown ice maps show .75 to 1.00" of ice.  Even if that is 50% overdone, this seems like a big deal up here???? 

[jbenedet]

Zzzzzzz

 

[wxeyeNH]

4 minutes ago, Typhoon Tip said:

No need to...  

the cold you are referring is particularly low level, and substantive in the mass loading into this system's preceding environment.  The "real" synoptic cold is still low ... 22-ish with DPs of 10 or so, but with such limited +PP ( positive pressure pattern (high pressure) ) situated N, a 20 to 25 kt sustained 925 mb low arriving flow will change the setting very quickly.   

These metrical limitations on this system are not going anywhere.   They are a predicament/detriment to this system's ability to maintain froze or freezing profiles.    

Lemme tell you something ... in late January 1994, we awoke one faithful morning to Winter Weather Advisory headlines in place, a temperature of 9 F on the weather lab's tele, and periodic flurries/grits coming down in the blue light of dawn throughout the Merrimack Valley.  Deep winter was in place.   By noon, sleet pellets had broken out, there was a south breeze, and the temperature had risen to 23 or so...  By 3 pm, it was 31 F with steady freezing rain.  By 6pm, it was 53 F with wildly swaying tree tops, and ice fog rolling off the snow pack and piles.  By 9pm, it was 61 F with 55 mph gusts.     

9 to 61, in 12 hours.   All because a cutter went through BUF-ish, and had no antecedent +PP to protect from the arriving WCB ( warm conveyor belt ) -related wind field.  

Now, this situation doesn't have a 65 kt 920 mb jet core fire hosing at it... but, the 40 kts with no leading surface high is going to still reverse the tables and do it probably at a speed that comes to some surprise to people, even in the valleys.  

I just saw this right after I made my post.  Would all these negative factors apply for us up here too?

[dendrite]

Gotta separate QPF as ZR and actual accretion too. I think you’ll have some decent icing up there around 1k Gene. But there’s really no ageostrophic lower dewpoint drain to offset the diabatic warming so once the ZR begins it’s a slow trend upward to 32°. I think we’ll probably wedge into the 30s until the cold fropa, but I think any additional accretion ends here in the morning and maybe mid to late morning up there.

[jbenedet]

Freezing is a warming process. Temps will spike quickly to 32 everywhere except the valleys of NNE. 

[ORH_wxman]

9 minutes ago, Typhoon Tip said:

No need to...  

the cold you are referring is particularly low level, and substantive in the mass loading into this system's preceding environment.  The "real" synoptic cold is still low ... 22-ish with DPs of 10 or so, but with such limited +PP ( positive pressure pattern (high pressure) ) situated N, a 20 to 25 kt sustained 925 mb low arriving flow will change the setting very quickly.   

These metrical limitations on this system are not going anywhere.   They are a predicament/detriment to this system's ability to maintain froze or freezing profiles.    

Lemme tell you something ... in late January 1994, we awoke one faithful morning to Winter Weather Advisory headlines in place, a temperature of 9 F on the weather lab's tele, and periodic flurries/grits coming down in the blue light of dawn throughout the Merrimack Valley.  Deep winter was in place.   By noon, sleet pellets had broken out, there was a south breeze, and the temperature had risen to 23 or so...  By 3 pm, it was 31 F with steady freezing rain.  By 6pm, it was 53 F with wildly swaying tree tops, and ice fog rolling off the snow pack and piles.  By 9pm, it was 61 F with 55 mph gusts. Student around the campus had spilled into the commons and down town in Lowell, in short sleeve shirts to finalize the defiance in mockery of winter...  

9 to 61, in 12 hours.   

All because a cutter went through BUF-ish, and had no antecedent +PP to protect from the arriving WCB ( warm conveyor belt ) -related wind field.  

Now, this situation doesn't have a 65 kt 920 mb jet core fire hosing at it...no.  But, the 40 kts with no leading surface high is going to still reverse the tables and do it probably at a speed that comes to some surprise to people, even in the valleys.  

I hated that storm but always love your account of it. We almost got our pack wiped in that one. Only reason we didn’t was because there was so much sleet and water equivalent in it from like 5 previous high QPF events that had started with the Dec 29-30, 1993 storm.
 

But it was mowed down to about 2” of glacier. 

[Damage In Tolland]

10 minutes ago, dendrite said:

Maybe one of those setups where you shoot up to 40° while Ryan is still -ZR in WeHa?

Yeah 

[dendrite]

And to Tip’s point….

A short period of +RA with marginal <32° temps and no evaporative cooling offset isn’t going to result in significant accretion. A lot of that liquid will run off and “waste” to the ground. 

[dendrite]

But it only takes 15 minutes of freezing drizzle to turn I93 into a demolition derby. At least the state piled a couple hundred thousand pounds of salt on the highway for the 1” the other day so the salt residue remains.

[ORH_wxman]

3 minutes ago, dendrite said:

And to Tip’s point….

A short period of +RA with marginal <32° temps and no evaporative cooling offset isn’t going to result in significant accretion. A lot of that liquid will run off and “waste” to the ground. 

Anytime I see 925-950ish going above  0C relatively quickly, I sell big ice accretion. You’d need something super inverted like 20F at the sfc to overcome the warm drops. 

[Typhoon Tip]

23 minutes ago, wxeyeNH said:

Tip, yesterday, Dandy was also not very impressed for even up here.  What am I missing?   1.25" of liquid, temperatures in the mid to upper 20s rising to around 32F tomorrow afternoon.  Longer precipitation time up here too.  Weather bell clown ice maps show .75 to 1.00" of ice.  Even if that is 50% overdone, this seems like a big deal up here???? 

I'm telling you the synoptic limitations that are in the actual models.   The interpretation after the fact, not sure where this 'I gotta bad feeling ...' trope is necessitated from.  

Using your worlds, we can't even support the doom interpretation:    'even if 50%'

...well, 50% of what.   .9 accretion?   that's arithmetically only .45, less than standard warning ice. 

Ice "storms" don't typically manifest the way this is modeled for a reason. 

The event timing is too fast.  Falls rates may be moderate, and accretion efficient for a time, but it's moving off way, waaay faster than climo icestorm typology.   Yeah, 2007 ... but that was a unique situation, and it was also longer than this will be, too.   

As icing sets up, it release latent heat of phase change; there need be a constant lower DP source to offset this physical process of fixing.    There is no source for that.   

EDIT,   ah, I just saw you responded.   

[wx2fish]

Hrrr is also on the southern edge of guidance with the initial waa burst. Nam/euro are further north with the bulk of it and have alot less qpf from SNH southward

[powderfreak]

7 minutes ago, dendrite said:

And to Tip’s point….

A short period of +RA with marginal <32° temps and no evaporative cooling offset isn’t going to result in significant accretion. A lot of that liquid will run off and “waste” to the ground. 

Yeah if you are getting 0.10”/hr or more QPF, even at 28F, that’s going to try very hard to quickly get to 32F through latent heat release.

I think we see a lot of 0.1-0.25” type ice with driving on cold pavement, cold dirt roads and side roads as the bigger issue.

[Typhoon Tip]

37 minutes ago, powderfreak said:

Yeah if you are getting 0.10”/hr or more QPF, even at 28F, that’s going to try very hard to quickly get to 32F through latent heat release.

I think we see a lot of 0.1-0.25” type ice with driving on cold pavement, cold dirt roads and side roads as the bigger issue.

satisfied with WWA ...  just the grease factor is enough to send SUVs pirouetting down highways while the entitled arrogance at the wheel is all confused how their assumption-mobile is doing that.   

I seriously saw this once.  Maybe some kind of overpass web-cam situated overlooking stretch of Dallas highway ... with an assortment of SUVs parked at angles in the median and shoulder, while egular sedans at least limped slowly through in curiosity before going about their way.  Next SUV comes into the frame spinning around ...smash!    Next Toyota Corrola slips through the scene ... This went until the video clip ended where SUVs blithely spun out of control through and/or into the carnage, while the supposedly less safer, materialistically humbler types, traversed the icy risk like a cat tip-toes along a narrow fence line - even if a paw slipped a little, they regrouped and spanned the distance unscathed.   

One of my favorite things in life LOL is watching presumptions fail

I never got a full explanation but ...it seems to me, 3.5 ton 60k SUVs might be overrated in popularity  

[moneypitmike]

46 minutes ago, HoarfrostHubb said:

5” of fluff will be decimated, even with the cold rain.     Swiss cheese incoming

I was thinking the same thing.  The Maine storm was really dense--and more of it.  We'll be fine there because of that.

[wx2fish]

25 minutes ago, dendrite said:

But it only takes 15 minutes of freezing drizzle to turn I93 into a demolition derby. At least the state piled a couple hundred thousand pounds of salt on the highway for the 1” the other day so the salt residue remains.

The salt usage is an interesting debate. Studies show far more is used than is needed, leading to increasing environmental impacts. On the other hand, it can be snowing 1"/hr and people are still blasting road conditions on social media. 

93 goes between Canobie Lake and Cobbetts Pond here in Windham and both have elevated chloride levels. 

[jbenedet]

The HRRR is way too cold vs all guidance, tonight.

No reason to buy that with the clouds moving in after sunset and torching above the surface starting by midnight.

[SJonesWX]

9 minutes ago, wx2fish said:

The salt usage is an interesting debate. Studies show far more is used than is needed, contributing to  increasing environmental impacts. On the other hand, it can be snowing 1"/hr and people are still blasting road conditions on social media. 

93 goes between Canobie Lake and Cobbetts Pond here in Windham and both have elevated chloride levels. 

Didn’t the state agree to use less salt in that area of I-93 as part of the widening project?

[dryslot]

This looks like its going to be meh on the ice here.

[wx2fish]

7 minutes ago, SJonesWX said:

Didn’t the state agree to use less salt in that area of I-93 as part of the widening project?

I think the state has been reducing usage to some degree. I think they are trying to get contractors to use less overall too. 

[HoarfrostHubb]

My town uses the liquid brine stuff on the main roads, but then the greenish colored salt mix on our side roads.     They will probably be plowing during the rain anyway, digging up our wrecked road