Chicago Storm

It's early, precip still has a long way to go to fill in.

You shouldn't be shocked. This is like clockwork when there's strong WAA.

Temps around 32 now for southern CWA.

The really sharp cutoff will be around DeKalb up to Fox Lake it looks like, for now.

Temps are definitely warming ahead of the pace as shown on colder guidance. The HRRR is pretty close to what's actually being realized, so I see no reason to deviate from it's output for now...And it's actually a bit too cold in some locations. Thus, still looks like front end mix (mostly FRZRA), before turning to plain rain for most the the area for the heart of the storm, then ending as a bit of snow. 0.10"+ ice, 1" snow and a lotta rain at ORD is the call. Looks like a nice hit for snow up by DBQ and RFD, with 6-12".

Glaze of ice on all surfaces with FZDZ/-FZRA here this morning.

If the NAM/UKMET score here, well, I'm going to be hella wrong.

Interesting setup right now with LES... You have a meso-low near downtown, with the convergence boundary extending SW from there, moving NW. This is going to help pull LES as far inland as LaSalle and DeKalb CO’s. .

A non-NAM solution is the way to go, which means some snow/freezing rain on the front end, before a switch to all rain for the rest of the event. I’m not buying into the more southern/weaker solutions, and I’m definitely not buying into the nonsense the NAM is showing. We’ve seen this all before where some models think enough cold air will hang on, and people believe it because of a snow pack in place to the south, only for WAA to win anyway. This will be no different. .

They’re done until tomorrow night. As per usual, the band progressed eastward faster than expected, and didn’t organize until later than expected. .

There’s been LES as far south as CMI tonight. .

ORD is at 5" so far, pending LES.

6.7” here for synoptic snows. Probably will get in a bit on LE eventually. .

It’s been sitting up there all night. .

Up to 5.3” here now. .

Pretty close to +SN here right now...just pouring snow. +SN DPA.

Up to 4.0" here. A E-W band of moderate to heavy snow has now given way to a NE-SW oriented moderate to heavy band of snow. 6"+ here is a lock now for sure, with amounts in the RAP/HRRR range of 6-10" likely.

Nice moderate to heavy band of snow setting up from around GBG up to ORD. This should slide northeast the next several hours.

Up to 2.6" here. Close to 1"/hr rates now.

Nice lake enhancement continues from north of MKE down into far NE. Illinois.

1.7" here thus far.

It's working in our favor in the end, as totals will likely be higher in the current scenario.

Probably an outside chance of TSSN across Northern Illinois tonight. Convective looking precip moving northeast out of the W. Illinois and STL area, where lightning has already occurred. NAM soundings also show a bit of CAPE in the DGZ around 9z at ORD.

3-4" range based on LSR's.

Highest totals will definitely be south of there.