Monday Feb 15 - midday Feb 16, 2021 Significant Winter Ice Event interior

[HVSnowLover]

1 hour ago, wdrag said:

5PM check in: Kind of looks like a 12-18 modest ice storm ~0.15-0.40" glaze for the I84 corridor, especially high terrain.  Non-freezing rain will probably encroach to near I80 in NJ and southern CT near I95. Here's a graphic from WPC.   Probably begins late 15 and ends Tuesday sometime toward midday?  At 536PM, added the new 72 hour statistical prob of 1/4" glaze. Pretty high prob down here in NNJ. 

Interesting how far south the 40-50% of .25 ice is, guess not that convinced it will be plain rain.

[HVSnowLover]

3 hours ago, Northof78 said:

Did it show any snow on the front end?

No, precip type looks pretty much the same from start to finish so for those who end up with ZR ouch.  

[LibertyBell]

5 hours ago, HVSnowLover said:

Even Central Park has a dewpoint of 30 at the height of the storm which would be a red flag for ice potential on the Euro   

the dew point is the temperature which the ground cools down to isnt it?

 

[wdrag]

513 AM/14 - will fully update by 915A today. It's Valentines Day. Hope all is going well. Rain LI for this event- some of it heavy. Topic headline changed a bit to further add some detail. 

Otherwise, certainly an Advisory event coming inside of I-95 Monday-Tuesday morning. There is a low probability of Watch-Warning verification ne PA/nwNJ/se NYS and N CT part of the forum for ice but questionalbe we can get to 1/2" damaging ice qualifying for a warning.  I suspect there will be some damage and power outages if the furnace (borrowed from others on the forum) RGEM continues this cold but possibly below warning criteria.  The GFS is warm tho its 06z version looks slightly colder. The GFSV16 is colder than it's soon outgoing GFS op and it holds to the 0.2-0.4" FRAM ice accretion for the event, which begins sometime Monday and ends midday Tuesday.  I still don't have a good feel for Monday but modeling is trending to agree with prior versions(from at least back to 00z/13) of the GGEM/RGEM that our untreated surfaces problems begin Monday during the day, especially afternoon.  Need more time to assess.    My feeling is the leftover advisory from this morning complicated multiple confusing headlines for the NWS and the idea, take one event at a time.  More later with graphics. 

[bluewave]

The 3km NAM has heavy elevated convection Tuesday morning. So maybe some poor drainage flooding with any storm drains that are blocked by snow. Could also lead to some basement flooding where there is snow packed near the foundations.

 

[MJO812]

Euro is warmer for Tuesday

Maybe a more amped storm for Tuesday will help with a bigger front end thump for Thursday.

[wdrag]

First: The GGEM/RGEM are going to win this Monday battle of no precip vs freezing precip occurring. The 06z EC and lesser so GFS, are capitulating to a two part event beginning Monday morning.  The 06Z EC gets this going pretty fast before dawn Monday.  

 

I'll get the OBS thread going around 9PM tonight... and to keep it simple, will combine both the front end Monday morning with the primary Monday afternoon-Tuesday morning event.  Problems for us will be developing.  Added NWS 09z/14 ensembles for .10 glaze and .25" glaze (threshold to begin power outages, the grow much larger when 0.50 glaze ) and added the 5AM view of NWS snowfall expected by Tuesday evening.  

[gpsnavigator]

Is that sounding really showing a temperature of 60°F at the 850 mb level?

[MJO812]

Alot of rain coming for the coast

[SnoSki14]

Some flooding issues probable Tuesday. 

[sferic]

1 hour ago, wdrag said:

First: The GGEM/RGEM are going to win this Monday battle of no precip vs freezing precip occurring. The 06z EC and lesser so GFS, are capitulating to a two part event beginning Monday morning.  The 06Z EC gets this going pretty fast before dawn Monday.  

 

I'll get the OBS thread going around 9PM tonight... and to keep it simple, will combine both the front end Monday morning with the primary Monday afternoon-Tuesday morning event.  Problems for us will be developing.  Added NWS 09z/14 ensembles for .10 glaze and .25" glaze (threshold to begin power outages, the grow much larger when 0.50 glaze ) and added the 5AM view of NWS snowfall expected by Tuesday evening.  

Walt, the total snowfall graphic for the NE do you have a link to that graphic? Thank you!

[sferic]

@snywx @Ericjcrash @crossbowftw3  I thing if we wind up with 3-6 inches total  by 00z Saturday we'll call it a win. Too much warmth rearing its ugly nose to kill all snow threats through the week thereby greatly  lowering the expectations of 12+ for our counties. Agreed?

[crossbowftw3]

3 minutes ago, sferic said:

@snywx @Ericjcrash @crossbowftw3  I thing if we wind up with 3-6 inches total  by 00z Saturday we'll call it a win. Too much warmth rearing its ugly nose to kill all snow threats through the week thereby greatly  lowering the expectations of 12+ for our counties. Agreed?

3-6 and icing of up to .25 makes sense at this juncture for tomorrow into Tuesday

[sferic]

Just now, crossbowftw3 said:

3-6 and icing of up to .25 makes sense at this juncture for tomorrow into Tuesday

How much additional would you guess with the Thursday event?

[eduggs]

2 hours ago, gpsnavigator said:

Is that sounding really showing a temperature of 60°F at the 850 mb level?

It looks like about 53°F. The dashed temperature lines are slanted at about 60 degrees.

[crossbowftw3]

1 minute ago, sferic said:

How much additional would you guess with the Thursday event?

I could probably say a similar theme to tomorrow but not 100% sure yet 

[sferic]

Just now, crossbowftw3 said:

I could probably say a similar theme to tomorrow but not 100% sure yet 

As long as my 20 inch base can rise I'd be happy

[hudsonvalley21]

Just now, sferic said:

As long as my 20 inch base can rise I'd be happy

Wouldn’t mind seeing some rain Tuesday to reduce the ice damming in gutters up this way. Then let’s add to the snowpack on Thursday 

[crossbowftw3]

Overall ZR QPF has gone up some on model runs. With typical paring techniques I think a reasonable high end is probably around .6” in the highest elevations that never get warm.

[wdrag]

39 minutes ago, sferic said:

Walt, the total snowfall graphic for the NE do you have a link to that graphic? Thank you!

https://www.weather.gov/erh/gis_wfo?id=ALY

 

Slider bar down to the regional and lower right is the map. 

 

Updates usually 2 hours after the 330A-330P packages.  So the 5A/5P are best for an overall depiction.

It updates throughout the day but takes a while for the local WFO amounts to change in the map. 

[wdrag]

The following 1154AM/14 update is for those concerned about power Monday night. The NWS ensemble mean glaze forecast (Sunday more ing update) is out for Monday-Monday night. The blue is 1/2", the dark green is 1/4". If you're anywhere with the dark green/blue, be aware you may not lose power Tuesday morning. This guidance may shift a little northwest on Monday with the southeast edge and total amounts possibly high by 1 or 2 tenths of an inch. Still, this guidance is heftier than what was projected for NC/VA and they got hit pretty hard. Difficult Monday night ahead and results for Tuesday morning may be problematic. My "guess" is a Winter Storm Watch "may" be issued ~330PM, for a Monday night ice storm in the blue area. 

 

[SnoSki14]

Thursday is looking like the more wintry threat as models amp up Tuesday.

Could end up being a SWFE or even a later stage Miller B.

[eduggs]

Currently light snow falling in Montville, NJ. Seems to be snowing below the radar.

[White Gorilla]

32 minutes ago, wdrag said:

The following 1154AM/14 update is for those concerned about power Monday night. The NWS ensemble mean glaze forecast (Sunday more ing update) is out for Monday-Monday night. The blue is 1/2", the dark green is 1/4". If you're anywhere with the dark green/blue, be aware you may not lose power Tuesday morning. This guidance may shift a little northwest on Monday with the southeast edge and total amounts possibly high by 1 or 2 tenths of an inch. Still, this guidance is heftier than what was projected for NC/VA and they got hit pretty hard. Difficult Monday night ahead and results for Tuesday morning may be problematic. My "guess" is a Winter Storm Watch "may" be issued ~330PM, for a Monday night ice storm in the blue area. 

 

Walt, I see the blue mostly in the higher elevation locations.  I am hoping our lower elevation in the mid Hudson Valley will reduce power outage potential. 

[Brian5671]

4 minutes ago, Brett said:

This looks like a pretty nasty ice storm

mostly rain on today's runs....

[SnowGoose69]

9 minutes ago, SnoSki14 said:

Thursday is looking like the more wintry threat as models amp up Tuesday.

Could end up being a SWFE or even a later stage Miller B.

Alot can still change but whenever you see lousy res models like GFS at 90 plus hours showing event starting as snow, it IS gonna start as snow.  Its too early right now to know if its 2 inches or 6 before the changeover but I'm confident it starts as snow

[White Gorilla]

25 minutes ago, Brian5671 said:

mostly rain on today's runs....

I don't mind getting rain, will reduce power outage risk up here 

[HeadInTheClouds]

4 minutes ago, Brian5671 said:

mostly rain on today's runs....

Yeah thats 1 model along with Icon that Im not going to trust with thermal profiles being so critical. All other models show icing being a potential problem N and W. 

[weatherpruf]

13 minutes ago, White Gorilla said:

I don't mind getting rain, will reduce power outage risk up here 

We dodged one bullet let's hope we can dodge a couple more.

[snywx]

1 hour ago, sferic said:

@snywx @Ericjcrash @crossbowftw3  I thing if we wind up with 3-6 inches total  by 00z Saturday we'll call it a win. Too much warmth rearing its ugly nose to kill all snow threats through the week thereby greatly  lowering the expectations of 12+ for our counties. Agreed?

I don’t see much snow falling tomorrow or Tuesday for the 84 corridor. Some sleet and a decent amount of ZR is prob the likely outcome for these parts. Up by you in northern Sullivan I can see 3” or so falling followed by some icing. Thursday looks a bit snowier