Feb 7th-9th event

[McHenrySnow]

I could definitely see the band setting up a bit further north, especially the further east you go keeping everything Purdue mentioned in mind. Still won't allow myself to hope for more than an inch at this point. RAP and HRRR have been consistent with some better snows across McHenry and Lake than originally forecasted (marginally). 

[cyclone77]

Wow this stuff is adding up extremely quickly.  Already a good half inch of fluff with very large flakes raining down.

[A-L-E-K]

best kind of report^

[hlcater]

Photogenic stuff coming your way. Massive flakes. 

[janetjanet998]

AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL  
1203 PM CST MON FEB 8 2021  
   
UPDATE  
  
1203 PM CST  
  
HAVE ISSUED A TARGETED, IMPACT-BASED WINTER WEATHER ADVISORY FOR  
AREAS ROUGHLY NEAR AND NORTH OF I-80 TO ROUGHLY SOUTH OF I-90.  
SUPPORTING FACTORS FOR HEADLINE ISSUANCE INCLUDED: OVERPERFORMANCE  
OF THE OVERNIGHT-MORNING SNOW SOUTH OF I-80 DUE TO VERY HIGH   
SLRS AND LIKELIHOOD OF HIGH (20-25:1) SLRS WITH PM SNOW; UPSTREAM  
RADAR PRESENTATION OF A HEAVIER FRONTOGENETICALLY DRIVEN SNOW   
BAND FROM IA INTO NORTHWEST IL; EXTRAPOLATION OF THIS BANDING   
ACROSS THE HEART OF THE CHICAGO METRO THROUGH THE PM COMMUTE; AND  
ROAD TREATMENTS BEING LESS EFFECTIVE DUE TO THE COLD AIR TEMPS.   
HAVE INDICATED 1-3" SNOWFALL AMOUNTS IN THE ADVISORY AREA, MOST OF  
WHICH WILL FALL BETWEEN NOW AND THE END OF THE EVENING COMMUTE  
(WITH RATES UP TO 1/2"/HR). REDUCED VISIBILITY WILL ALSO BE AN   
ISSUE IN THE HEART OF THE SNOW BAND, AS VISIBILITY AS LOW AS 1/2   
MILE HAS BEEN NOTED UPSTREAM.  
  
LIGHTER SNOW HAS ALSO FILLED IN SOUTH OF THE BAND INTO WEST CENTRAL  
ILLINOIS, BUT THIS SHOULD PRODUCE LIGHTER AMOUNTS UP TO 1". IF  
INTENSITY OF THE SNOW SOUTH OF THE MAIN BAND PICKS UP THIS  
AFTERNOON, MAY NEED TO CONSIDER EXPANDING THE ADVISORY. THIS ALSO  
INCLUDES THE WISCONSIN STATE LINE COUNTIES. WE CURRENTLY LEFT  
THESE OUT OF THE HEADLINE, BUT IF IT LOOKS LIKE THE BAND WILL GET  
INTO THESE COUNTIES, WILL MAKE A DECISION OVER THE NEXT COUPLE  
HOURS ON WHETHER THE WWA NEEDS TO BE EXPANDED NORTH AS WELL. THE  
SNOW SHOULD TAPER THIS EVENING AS BANDING SHIFTS EAST, THOUGH  
THERE'S CONCERN FOR SOME RE-INVIGORATION OF LOW-MID-LEVEL F-GEN  
(850-700 MB) OVERHEAD THIS EVENING. ADVISORY END TIME WAS SET AT  
10PM GIVEN UNCERTAINTY ON ENDING OF STEADIER SNOW. NEXT ITEM TO  
ADDRESS WILL BE LAKE EFFECT SNOW POTENTIAL INTO NORTHWEST INDIANA  
INTO TUESDAY, WHICH WOULD ADD ADDITIONAL SNOW THERE.  
  
NOT MENTIONED IS THE VERY COLD TEMPS, WHICH IF CLEARING OCCURS  
TONIGHT, COULD CERTAINLY BE COLDER IN SPOTS THAN GOING OFFICIAL  
FORECAST LOWS FOR EARLY TUESDAY.  
  
CASTRO  

[tuanis]

That’s a solid looking band. Should lead to some surprises.

[hawkeye_wx]

Even here on the northern edge of the band, the flakes are large and floating down like feathers.  I just wish it was heavier.

[cyclone77]

Over an inch now.  There was a slight letup with smaller flakes, but it's pouring fatties again.  

[Malacka11]

Shooting for three inches here

[Cary67]

Will go 1" here. Lightly snowing

[A-L-E-K]

nice flake size, little wind, daylight hours...not too bad

[fyrfyter]

Models are averaging out around 3-4" tonight. Should be a nice event for the area down here. That should be enough to close most schools. 

[hlcater]

Will talk away with about 2" here. Still coming down at a moderate clip but not for much longer

[Baum]

this is it?

[Dalfy]

Very light flurries in downtown STL @ a balmy 23. Most of the precip has been to the north and south of me

[cyclone77]

Closing in on 2", still coming down nicely.  14-15" of snow OTG now with 3 layers of ice within, the bottom of which is at least an inch thick.  No above freezing temps in sight.  Deeeeeeeep winter.

[SchaumburgStormer]

7 minutes ago, cyclone77 said:

Closing in on 2", still coming down nicely.  14-15" of snow OTG now with 3 layers of ice within, the bottom of which is at least an inch thick.  No above freezing temps in sight.  Deeeeeeeep winter.

Those layers of ice are priming you for a big avalanche. Avoid any slopes and hills    

[hawkeye_wx]

I'm at about an inch so far.  It's a bit clumpy.  Unlike the disappointing 10:1 snow a couple days ago, this stuff is pure dandelion fluff.

[janetjanet998]

18z NAM still clueless only around an inch 

19z HRRR dumps 3+ in IA but then the band goes poof starting about now  (been doing that all morning, weakens the band 1-2 hours after the runtime) 

[McHenrySnow]

Incredibly frustrating to keep barely missing out. Yes, they're minor events, but they add up, as many of you can attest and with this cold and dry pattern, any amount is appreciated. 

[blue60007]

Nice banding showing up across KIND, snowing nicely here, clearly some good forcing overhead. Good flake size, and looks even heavier to the east. Wasn't expecting anything so soon.

[Cary67]

1 minute ago, McHenrySnow said:

Incredibly frustrating to keep barely missing out. Yes, they're minor events, but they add up, as many of you can attest and with this cold and dry pattern, any amount is appreciated. 

Heavier band seems to have set up between Elgin and Aurora

[Indystorm]

Gentle medium size snowflakes falling nicely here in Griffith....looks very peaceful as I look out the window.

[Baum]

starting to see a few large flakes mixing in with the ongoing dust.

[mimillman]

Mood flakes all day but no accumulation

[Frog Town]

3 hours ago, purduewx80 said:

this is where old-school meteorology gave us some clues for today. not too surprising that fgen forcing is more intense than modeled given this jet streak passing by (it gradually lifts NE from where it's shown below). shame it won't be in place longer than a few hours. That said, there is focus at 700mb through the night, so light snow may end up persisting all the way into tomorrow morning in the general areas its occurring now.

The radar is looking way more solid than the modeling.  Purduewx80 was spot on in his analysis!

[Baum]

^

I'll pass out kudos when I have 3-4" of fluff down. Snowing light to moderate with nice dendrites now.

[Indystorm]

I-88 should be doing very nicely per current radar returns from the burbs out west into IA.

[purduewx80]

11 minutes ago, Baum said:

starting to see a few large flakes mixing in with the ongoing dust.

strange you haven't had larger flakes more frequently. suspect we are seeing some lake enhancement in chicago, because there have been large flakes falling at varying intensity since i woke up this morning. 

shame for those on either side of the band coming in, which will only end up being about 20 miles wide.

still watching a possible 2nd round of enhancement overnight, although it seems evident from radar and obs in IA snow will keep going through the evening. would watch areas near and just south of the best snow this afternoon, probably in chicago from ~9pm - 1am. dry air will start to come in and the lift isn't necessarily perfectly centered in the DGZ w/ that round, so it may not be as effective as this afternoon's. 

[Radtechwxman]

3 hours ago, janetjanet998 said:

either models are slow with developing the snow band (had nothing now) or they are completely missing it this morning

 

so the question is are models just too slow with the system and the snow band developed faster and will move out faster resulting in the same amount of snow

OR

is this bonus snow that the models missed this morning and no change with the afternoon and overnight timing?

Looks more like scenario 1 more likely. Lol. Models did bad today. Now models aren't showing much here Wed and Thurs but is that trustworthy after today?