11/8-11/10 First Snow and Lake Effect Event

[Chicago916]

1 minute ago, OHweather said:

I don't think the band taking slightly longer to swing west is a bad thing for the immediate lakeshore/Chicago area (and probably ups the odds at someone getting a higher-end total)...some earlier model depictions had it swinging west and breaking into weaker multi-bands pretty quickly (before congealing as it swings back east on Monday). This slower west push right now may allow for a more focused band that lasts longer close to the lake later tonight. 

That more or less seems like what LOT just hinted at on Twitter too. Less likely there will be "slight break before a 2nd band". Seems to imply this will be the sole band now. Definitely would boost odds of some higher totals. 

[migratingwx]

 

 Mesoscale Discussion 2202
   NWS Storm Prediction Center Norman OK
   0955 PM CST Sun Nov 09 2025

   Areas affected...Northwestern Indiana and northeastern Illinois

   Concerning...Heavy snow 

   Valid 100355Z - 100900Z

   SUMMARY...An intense lake effect snow band will drift slowly
   south-southwestward across northwestern Indiana and northeastern
   Illinois through the early morning hours. Heavy snowfall rates of 2+
   inches/hour are expected under the core of the band.

   DISCUSSION...Regional radar data shows a well-defined snowband
   favorably oriented along the long axis of Lake MI. This snowband is
   on the backside of a mesoscale low that evolved off of Lake MI and
   is moving slowly southward across far northern IN. As this feature
   continues southward, and low-level flow continues veering to a
   north-northeast direction over Lake MI, the band will have a
   tendency to drift gradually south-southwestward across far
   northwestern IN and northeastern IL through the early morning hours.
   The 00Z GRB sounding sampled very cold temperatures aloft (-40C at
   500 mb), which is yielding steep low/midlevel lapse rates and a deep
   convective boundary layer (aided by relatively warm lake waters). 

   Given the favorable/persistent orientation of low-level flow down
   Lake MI and significant convective enhancement, heavy snowfall rates
   of 2-3 inches per hour are expected under the core of the band as it
   continues south-southwestward. Isolated lightning flashes will also
   be possible. There will likely be a sharp drop-off in the heaviest
   snowfall rates as the band tracks southwestward across northeastern
   IL (owing to less favorable thermodynamic conditions), though
   exactly where this will occur is uncertain. Additionally, gusty
   winds within the band will yield significant visibility reductions
   where snowfall rates are maximized.

   ..Weinman.. 11/10/2025

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...IWX...LOT...

   LAT...LON   42278765 41998745 41768708 41818669 41608645 41248667
               41228727 41438787 42008820 42268810 42358788 42278765

[OHweather]

14 minutes ago, Chicago916 said:

That more or less seems like what LOT just hinted at on Twitter too. Less likely there will be "slight break before a 2nd band". Seems to imply this will be the sole band now. Definitely would boost odds of some higher totals. 

Yeah it seems like they're alluding to it in their AFD as well. It may be hard to know exactly which way it'll go until the mesolow pushes farther inland/weakens a bit over the next few hours, as that's when the band will be more free to whip west, which it will still want to do based on radar trends farther up the lake. However, the shorter the window for that to happen the better for getting the band to stay more coherent. 

[BuffaloWeather]

2 hours ago, A-L-E-K said:

On the board, curious how this plays out

You're about to see a Buffalo band, hope you're still awake for this. 

[OHweather]

Some pretty impressive ascent from the vort max and meso low! 

[Malacka11]

@A-L-E-K How is it

[homedis]

Pouring snow in Wicker Park area, flake size has definitely improved.

[sbnwx85]

whiteout on the lakeshore. You can also drag the cursor back to see what the shot normally looks like.

[andyhb]

How has no one said "rdy 2 b buried" yet?

[OrdIowPitMsp]

https://www.earthcam.com/usa/illinois/chicago/wrigleyfield/?cam=wrigleyfield_hd

[homedis]

Absolutely ripping here. This feels like thundersnow any mintue now…

https://imgur.com/a/6GqbyUD

[GaWx]

Just out from LOT (11:37 PM):

THE INITIAL PUSH OF SNOW THAT DROPPED VIS DOWN TO 3/4SM AT  
CHICAGO TERMINALS IS PUSHING SOUTHWESTWARD TOWARD KPIA. HOWEVER,  
THE NEXT BAND OF SNOW IS RIGHT ALONG THE LAKE SHORELINE AT THE  
TIME THIS DISCUSSION WAS PUBLISHED. CURRENTLY CONDITIONS AT  
CHICAGO TERMINALS ARE VFR, BUT WITH THE NEXT BAND ABOUT TO MOVE  
ONSHORE, THE TAFS WERE SENT WITH WORSE CONDITIONS DUE TO THE  
EXPECTATIONS THAT THINGS WILL DETERIORATE QUICKLY AFTER 06Z.   
THIS BAND WILL BE HAVE MORE VIGOROUS SNOW RATES AND STRONG GUSTY  
WINDS. LOW VIS IS EXPECTED, BUT MAY EXCEED EXPECTATIONS AND   
BECOME SUB-1/4SM. ADDITIONALLY, BUOYS HAVE ALREADY REPORTED   
GUSTS TO 31 KNOTS, AND WHILE 35 KNOTS IS IN THE TAF, IT IS   
ENTIRELY POSSIBLE THAT GUSTS TOUCH 40 KNOTS AT TIMES. IT IS   
POSSIBLE THE THE TEMPO FROM 06Z TO 09Z IS A HAIR LONG, BUT HAVE   
MODERATE CONFIDENCE THAT THERE COULD BE 3 HOURS OF REALLY   
INTENSE SNOW RATES.  
  
LOOKING AT REGIONAL RADAR, THERE IS A LONG LAKE ORIENTED BAND  
OFF THE WISCONSIN SHORELINE MOVING SOUTHWARD. THIS BAND WILL BE  
"ROUND 2" AS IT MOVES INTO ILLINOIS. THERE WILL THE EXPECTATION  
IS THAT THERE WILL PROBABLY SOME TIME OF "BREAK" IN THE INTENSE  
SNOW BEFORE IT MOVES SOUTHWARD (LONGER AT KMDW AND KGYY). CAN'T  
RULE OUT SOME QUICK VFR CONDITIONS, BUT FELT MORE PRUDENT TO   
LEAVE IFR/MVFR CONDITIONS FOR ONGOING SNOWFALL. NEVERTHELESS, A  
SECOND ROUND OF INTENSE LAKE EFFECT SNOW IS EXPECTED BEFORE  
DAYBREAK. 

[snowman33]

13 minutes ago, andyhb said:

How has no one said "rdy 2 b buried" yet?

Can't fathom what is happening, been burned too many times with LES.

[KeenerWx]

DAB+ vibes now locally as trajectory and upscale radar trends are not promising. Still an awesome event to watch unfold. 

[TheNiño]

40 minutes ago, andyhb said:

How has no one said "rdy 2 b buried" yet?

You’re so right haha 

[andyhb]

Visibility is effectively zero on that Skydeck webcam now.

[homedis]

Quite hard to measure with the wind gusts, but I’m measuring around 2.5” in the past hour. With close to 3” total accumulation thus far in Wicker Park.

[homedis]

THUNDERSNOW!!!

[Chicago Storm]

2 minutes ago, homedis said:

THUNDERSNOW!!!

Right over downtown on the feed.

[skiier04]

Saw the lightning flash from my hotel room in Chicago river north

[dmillz25]

My cousin say this is the heaviest snow he’s seen since the 2011 blizzard.

Edit and saw the thundersnow 

[Chicago916]

Some really high DBZ coming ashore now. Likely graupel/hail and more thunder to come

[Chicago Storm]

Just now, Chicago916 said:

Some really high DBZ coming ashore now. Likely graupel and more thunder to come

Someone I know has reported graupel.

[RCNYILWX]

I'm surprised [mention=3997]RCNYILWX[/mention] hasn't chimed in as of yet.

Just leaving a busy evening shift. TAF verified (edit: at MDW, need ORD still)

Sent from my SM-S936U using Tapatalk

[vortex]

Earth Cam from Chicago just now, compared to what it normally looked like earlier in the evening. 
 

[homedis]

Got two videos of the thundersnow… I can go to sleep in peace now.

https://imgur.com/a/pubD2KK

https://imgur.com/a/ZYInPQz