December 5-6, 2020 Storm Observations and Nowcast

[CoastalWx]

1 hour ago, mahk_webstah said:

Is it my imagination or is that happening more often lately with storms?

It can happen with a marginal airmass. I think many said it has big bust potential. 

[Damage In Tolland]

It really does the wonders for the soul and psyche to have snow during the holiday season. A rare snowy December morning . I know it’s gone by next weekend so will cherish while we have it.

[OceanStWx]

8 hours ago, STILL N OF PIKE said:

Did you have many reports from elevations or are those generally sparse ?

 Seems many in Maine Got tons of liquid but Missed warning snows by being about 500 feet Too low elevation . Just wondering what someone with another 500-800” elevation would have seen In interior SW Maine .

We were trying to tease out elevation from people when they called, but there aren't many people like Gene who know their elevation and all their neighbors elevations too. 

But I think it's clear that played a big role when you look at our office total vs up on Lava Rock. 

[mahk_webstah]

1 minute ago, CoastalWx said:

It can happen with a marginal airmass. I think many said it has big bust potential. 

You’re missing my larger question.  I don’t know the model verification scores on specific storms but it seems busts are more frequent last couple.  I realize it could be some sort of bias at play but it seems it’s been a bustorama latelu

[CoastalWx]

8 minutes ago, mahk_webstah said:

You’re missing my larger question.  I don’t know the model verification scores on specific storms but it seems busts are more frequent last couple.  I realize it could be some sort of bias at play but it seems it’s been a bustorama latelu

I think it’s recent confirmation bias. Maybe you are referring to marginal event busts? 
 

I wonder if you guys were sucking exhaust maybe? It seemed like anybody downwind of high terrain didn’t do well. I saw the signal at Winni and purposely did not go there. I knew it would suck there despite my son begging me lol. Being downwind of high terrain in a marginal airmass can suck.

[OceanStWx]

9 minutes ago, mahk_webstah said:

You’re missing my larger question.  I don’t know the model verification scores on specific storms but it seems busts are more frequent last couple.  I realize it could be some sort of bias at play but it seems it’s been a bustorama latelu

Well I think a problem is that clown maps (especially these realistic looking ones) are a relatively new feature. Because of how they are generated, you rarely end up seeing more snow than they spit out. 

[CoastalWx]

Just now, OceanStWx said:

Well I think a problem is that clown maps (especially these realistic looking ones) are a relatively new feature. Because of how they are generated, you rarely end up seeing more snow than they spit out. 

Too many get sucked in. 

[powderfreak]

3 minutes ago, OceanStWx said:

Well I think a problem is that clown maps (especially these realistic looking ones) are a relatively new feature. Because of how they are generated, you rarely end up seeing more snow than they spit out. 

I feel like we take the over on those too in a cold atmosphere... “ratios will be better than 10:1 so take the over on the snow maps”.

I just think they in general show too wide a swath of heavy snows in almost every storm too... large swaths of heavy snow often tighten up in reality.

[Great Snow 1717]

5 minutes ago, CoastalWx said:

Too many get sucked in. 

 

7 minutes ago, OceanStWx said:

Well I think a problem is that clown maps (especially these realistic looking ones) are a relatively new feature. Because of how they are generated, you rarely end up seeing more snow than they spit out. 

Agree. Yesterday's storm reminded me more of a mid March -mid April setup  than an early December storm. 

Kudos to the Weather Channel, on Friday evening they had forecasted 3 inches for much of the Merrimack Valley area. And in general were forecasting lower snowfall totals than the local TV mets. 

[Heisy]

33 minutes ago, HoarfrostHubb said:

Our son is working the lifts at WaWa. They were supposed to open at 7:30 but delays due to icing issues etc

I just woke up. Had to catch up a lot of sleep. Think I probably had 7? Melting started at tail end. Gonna wait to drive home as late as possible in day. Not the 12 I had hoped for, but idc worth it regardless. The chase is the best part!

[codfishsnowman]

9 hours ago, Typhoon Tip said:

Im thinking the last half of this system pretty much just didn’t happen? Certainly happened well shy of those late guidance last night ...they had moderate to heavy snow deep into the evening… interesting.

So we were done here by 4:30 or 5 o’clock this evening and we’ve had nothing but mist flurries and drizzle temperatures rising back to 34 ever since. 
 

I think I am kind of kicking myself for something I noticed yesterday. And it seems to be playing out here until I get a better explanation... 

I would say the last 1/3 of QPF from last night’s NAM over Eastern sections was thru a 320° wind.  I’ve noticed over the years that the NAM tends to hold onto substantial precipitation way too long when wind backs to the northwest around coastal events.  Rad is filled with what looks like probably chaff/virga  now. I’ve seen this before it’s like the models think this is heavy D form banding

Best post of this thread

[OceanStWx]

9 minutes ago, powderfreak said:

I feel like we take the over on those too in a cold atmosphere... “ratios will be better than 10:1 so take the over on the snow maps”.

I just think they in general show too wide a swath of heavy snows in almost every storm too... large swaths of heavy snow often tighten up in reality.

Today is fun, because now I can play Monday morning QB on myself trying to diagnose WTF went wrong.

[OceanStWx]

2 minutes ago, codfishsnowman said:

Best post of this thread

Tip is right, NW winds downslope for just about everyone across the region. That does a number on precip.

[moneypitmike]

52 minutes ago, White Rain said:

Glad I snow blowed the driveway up yesterday, it was very hard moving. Everything froze solid overnight. 

 

Alas, I had not.

Much regret this morning.

[dendrite]

2 minutes ago, powderfreak said:

I feel like we take the over on those too in a cold atmosphere... “ratios will be better than 10:1 so take the over on the snow maps”.

I just think they in general show too wide a swath of heavy snows in almost every storm too... large swaths of heavy snow often tighten up in reality.

I can’t remember such a wide swath of 33-35° heavy snows in December where it just couldn’t accumulate. The ground is relatively warm, it was a torch the day before, we started as a decent amount of rain, and we just couldn’t bulb it down to 32° and stay there. So we rack up 1-3” of w.e. and only a few inches of snow.

Maybe I’m wrong...I hadn’t been paying close enough attention after my back issues...but I thought initially there was supposed to be snow showers Fri night into Sat morning in NNE with the northern stream and when I woke up yesterday and still saw rain in N VT and BML/HIE I knew there was no cold to advect in. So when those east tics started coming I had a bad feeling being on the wrong side of the QPF gradient and west of the banding. That’s when our downslope kicks in. I at least had 3”, but Eek had a trace off the lake and 1P1 and LEB were mostly rain. It felt more like a late April event than near the winter solstice.

But yeah...the clowns suck and we have fun with them, but I think most know you have to look deeper when giving a forecast. They’re a quick and easy way to see the QPF as snow when using the 10:1’s. They obviously just didn’t work too well yesterday with the crap airmass. 

[CoastalWx]

5 minutes ago, OceanStWx said:

Tip is right, NW winds downslope for just about everyone across the region. That does a number on precip.

I think we had decent qpf here after 5. I know we had a big WAA event in early January 2010 where we had 12” on NW winds, so it can happen. I just think it was a garbage airmass and when you need all the pieces lining up for it to even snow, it’s probably not going to end well.

[STILL N OF PIKE]

I remember making a comment 2 days ago about a NNW wind direction from surface to 850 on models as max lift was suppose to arrive 18z to past 0 z (stinger) that did not materialize as forecast up to the event . Radar became a bit hit and miss but no death bands set up. 1/2 mile vis Snow didn’t cut it and it was sort of a double whammy effect on 2m temps (which didn’t have wiggle room in Merrimack valley ) . Overall thou ..I mean we got snow in a garbage airmass . I just don’t enjoy spending xyz hours time looking at models and trying to learn and then have sort of meh reasons for a model and forecast fail for my general area down thru metro west , given how things looked at 2pm

I’m trying to learn and I’m not trying to make it look like folks missed something 

[OceanStWx]

1 minute ago, dendrite said:

I can’t remember such a wide swath of 33-35° heavy snows in December where it just couldn’t accumulate. The ground is relatively warm, it was a torch the day before, we started as a decent amount of rain, and we just couldn’t bulb it down to 32° and stay there. So we rack up 1-3” of w.e. and only a few inches of snow.

Maybe I’m wrong...I hadn’t been paying close enough attention after my back issues...but I thought initially there was supposed to be snow showers Fri night into Sat morning in NNE with the northern stream and when I woke up yesterday and still saw rain in N VT and BML/HIE I knew there was no cold to advect in. So when those east tics started coming I had a bad feeling being on the wrong side of the QPF gradient and west of the banding. That’s when our downslope kicks in. I at least had 3”, but Eek had a trace off the lake and 1P1 and LEB were mostly rain. It felt more like a late April event than near the winter solstice.

But yeah...the clowns suck and we have fun with them, but I think most know you have to look deeper when giving a forecast. They’re a quick and easy way to see the QPF as snow when using the 10:1’s. They obviously just didn’t work too well yesterday with the crap airmass. 

Even Kuchera isn't going to save you in an event like this. 33F snow is still going to give you a 7:1 ratio. We were about half of that at the office from 1-7PM when it was nearly all snow/frozen.

[ORH_wxman]

3 minutes ago, CoastalWx said:

I think we had decent qpf here after 5. I know we had a big WAA event in early January 2010 where we had 12” on NW winds, so it can happen. I just think it was a garbage airmass and when you need all the pieces lining up for it to even snow, it’s probably not going to end well.

I think the key is probably the DGZ lift. My guess is the best DGZ lift stayed near 495 and westward for most of the storm. It also coincided with the higher terrain so we saw a bigger elevation gradient than usual. But even a lot of 495 belt with modest elevation in the Littleton to Berlin to Hopkinton/Holliston zone saw 4-6”...it was kind of telling to me that once you got further east on 495 like over to Lowell and Lawrence that they really struggled and I’m wondering if the longitude there hurt with worse DGZ lift. 

[dendrite]

Just now, OceanStWx said:

Even Kuchera isn't going to save you in an event like this. 33F snow is still going to give you a 7:1 ratio. We were about half of that at the office from 1-7PM when it was nearly all snow/frozen.

It felt like one of those midday April, brighter overcast deals where it’s melting at the bottom as fast as it’s trying to accumulate on the top. These were like sleet ratios or even worse.

[powderfreak]

8 minutes ago, dendrite said:

I can’t remember such a wide swath of 33-35° heavy snows in December where it just couldn’t accumulate. The ground is relatively warm, it was a torch the day before, we started as a decent amount of rain, and we just couldn’t bulb it down to 32° and stay there. So we rack up 1-3” of w.e. and only a few inches of snow.

Maybe I’m wrong...I hadn’t been paying close enough attention after my back issues...but I thought initially there was supposed to be snow showers Fri night into Sat morning in NNE with the northern stream and when I woke up yesterday and still saw rain in N VT and BML/HIE I knew there was no cold to advect in. So when those east tics started coming I had a bad feeling being on the wrong side of the QPF gradient and west of the banding. That’s when our downslope kicks in. I at least had 3”, but Eek had a trace off the lake and 1P1 and LEB were mostly rain. It felt more like a late April event than near the winter solstice.

But yeah...the clowns suck and we have fun with them, but I think most know you have to look deeper when giving a forecast. They’re a quick and easy way to see the QPF as snow when using the 10:1’s. They obviously just didn’t work too well yesterday with the crap airmass. 

Yeah I noticed when the accumulating snow level stayed at like 2,000ft on Friday night and then even up here at 1,500ft it rotted in the 34-35F range yesterday morning.  Modeled 2-M temps were off up here by 3-4F yesterday morning.  Good red flag.  

And also agreed on the snow maps... it's a very basic way to find the QPF that should fall as flakes, accumulation regardless.

[HIPPYVALLEY]

Sugarloaf is reporting 18” on the mountain. Boom. 

[CoastalWx]

10 minutes ago, ORH_wxman said:

I think the key is probably the DGZ lift. My guess is the best DGZ lift stayed near 495 and westward for most of the storm. It also coincided with the higher terrain so we saw a bigger elevation gradient than usual. But even a lot of 495 belt with modest elevation in the Littleton to Berlin to Hopkinton/Holliston zone saw 4-6”...it was kind of telling to me that once you got further east on 495 like over to Lowell and Lawrence that they really struggled and I’m wondering if the longitude there hurt with worse DGZ lift. 

That’s my guess too. Mentioned earlier about the DGZ coinciding with high terrain. I think longitude did hurt. Absolutely. 

[stormtracker]

Ended up with 13" here in Eustis, ME.  Was a beautiful night

[Ginx snewx]

2 hours ago, The 4 Seasons said:

anyone got CT final snow reports send em may way, ty

 

1.0 Moosup Ct 

[OceanStWx]

11 minutes ago, dendrite said:

It felt like one of those midday April, brighter overcast deals where it’s melting at the bottom as fast as it’s trying to accumulate on the top. These were like sleet ratios or even worse.

It takes some stones to forecast a significant period of 3:1 or worse ratio. 

[PhineasC]

14.4” is the official total in Randolph. 

[ORH_wxman]

1 minute ago, stormtracker said:

Ended up with 13" here in Eustis, ME.  Was a beautiful night

Zwyts sent me a pretty sweet video of solid wind/snow combo. I told him I was glad in retrospect that you guys went with the more elevated zone vs lower down on skowhegan/Millinocket...being at 1200 feet ended up being a bigger deal than initially thought. Y’all hovered just below freezing which was huge. 

[STILL N OF PIKE]

Just arrived at Miller State park 

Probably 3 distinct Elevation  zones on the way here from Nashua 

1. Nashua past Milford and into Wilton  (350 elevation and under ) . No snow on trees. Prob saw 3-4”

2. East Central  temple . 450 to 750 elevation. Snow increased rapidly on trees and some decent sag was visible , increased w elevation 

3. West temple and Miller State park 800-1100 feet . Gorgeous caked trees . White everywhere glaring in the sun light .

 

Heading up .

[RUNNAWAYICEBERG]

@The 4 Seasons 

0.5” in Southbury CT