Hoosier

Yep, these kinds of storms can turn out very well in the city proper even if heaviest synoptic band is south.

Might be safe to say I have never seen a model spit out 30" for LAF in one storm. 2 feet, yes

Nice to see this work out for someone.

If there is a band of sig ice (not yet certain) then it could be a problem with the wind component. Pressure gradient between that strong high and the low will ensure it's breezy even if sfc low isn't that deep.

Coming down nicely here right now.

Returns increasing over southern Lake Michigan...

Here's the evening afd from Gino. Gotta feel for the folks at LOT... so much bust potential being at the mercy of something of this nature in a highly populated area. Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 931 PM CST Thu Jan 27 2022 .UPDATE... Issued at 931 PM CST Thu Jan 27 2022 Have issued a winter storm warning for Lake IL, central, and northern Cook Counties and a winter wx advisory for DuPage, southern Cook, and Lake County IN. Regarding the synoptic and thermodynamic environment for lake effect snow (LES), no changes from thinking of the previous shift. Very favorable environment for a dominant, intense single lake effect snow band to develop and move ashore into northeast IL overnight into Friday morning. Forecast soundings show convective layer encompassing the entire dendritic growth zone (DGZ) and given the strong instability and expected land breeze convergence band, should see strong ascent through the DGZ. Set-up appears favorable for 2"+ per hour snowfall rates during the most intense portion of the LES band (09z-16z). There has been a near unanimous shift westward shift in hires guidance in the placement of the LES band, which places the risk of heavy snow farther north into the metro area. Unfortunately, there are inherent uncertainties that come into play when trying to forecast meso-gamma scale phenomena like this. It is also not uncommon for bands to "wiggle" around and there is still spread in the various hires guidance on placement of the band. While additional shifts in the forecast placement of the band are possible, we are within the time window that a decision needed to be made, so have trended the higher snow accumulations farther north and west, though not as far north and west as most of the 00z hires guidance. The westward shift in the guidance actually increases confidence that there could be a longer residence time for some areas. Confidence is increasing that max snowfall totals will end up at least in the 6-8" range and not out of the realm of possibility that there could be isolated double digit totals. Given the timing of this event (during the height of Friday morning rush hour) and the inherent uncertainties in exact placement of the band, opted to err a bit on the side of caution with headlines. Certainly plausible that band ends up just east of Lake IL and/or Dupage county, or stays mainly west of Lake IN, but felt the course of least regret was to go a little big and risk some headline areas falling short of expectations. The WSW and forecast grids are out and updated text forecast products will be issued momentarily. - Izzi

That 18z GFS got me pumped. Probably the most I have looked forward to a 00z cycle so far this winter. And then tomorrow 00z will be the most, and then the following 00z lol

Watching obs from the eastern side of the lake (Muskegon, Benton Harbor, etc) to see when winds turn offshore. Flow is still N/NNW over there.

Ouch. Trends def not looking good imby. Gotta hope the convergence zone doesn't shift away as quickly as progged.

Meh. I try to not get too heavily invested in these things ahead of time as there's too much that can go wrong and put the band somewhere else. At least there is a system to track after this passes.

I mean, it's a pos/neutral trough with no closed mid level low. That's what I meant. And as a result, the surface maps don't even look that impressive with a rather pedestrian sfc low.

Kind of a garbage look aloft on the 18z GFS, but goes to show that you don't always need a sexy appearance for big snows.

Would be crazy in Chi metro... all that powder with gusty winds enhanced by the lake.

Absolutely buried locally. Too bad it's several days out.

That's a nice look. Snows for a long time with only a brief break.

Ricky in on the afternoon afd Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 329 PM CST Thu Jan 27 2022 .SHORT TERM... Issued at 327 PM CST Thu Jan 27 2022 Through Friday... Bottom Line Up Front: 1. No changes planned to the ongoing Winter Storm Watch headlines (12am-12pm Friday) with the decision to upgrade to warning and potential expanded areal coverage of the advisory expected this evening. 2. Conditional threat for higher-end totals (6"+) exists near the lakeshore from Chicago south toward Gary, IN, but will be dependent on residence time of the heaviest snowfall rates under the lake effect band. 3. A quick dusting/coating of snow will be possible area-wide this evening and early overnight as scattered snow showers move across the area behind the cold front (before the lake effect band gets going). A cold front is currently in the process of moving across the area this afternoon. High temperatures today in the lower 30s were a welcome change from the cold the past few days. Some areas were even able to get some sun thanks to clearing behind the front. Clouds will quickly fill in this evening with increasing chances for scattered snow showers and flurries into this evening. These look to be fairly low impact, but there may be some minor visibility reductions and a dusting on surfaces that could make untreated roadways slick. Temperatures overnight fall into the single digits and teens which will allow any snow that falls to accumulate more readily. With the westward trend holding steady in the afternoon model guidance with respect to the lake effect snow band overnight into Friday morning, we have opted to not make any changes to the ongoing Winter Storm Watch. Will let the evening shift get another look at things as to whether confidence in a dominant band setting up in the watch area will warrant a Winter Storm Warning or Winter Weather Advisory for a more transient band. Conditions remain favorable for a heavy lake effect snow assuming a dominant single band evolves. Favorable fetch with north to northeast winds across the lake, strong lift in the cloud layer, and sufficient lake induced instability would support snowfall rates of 1 to 2 inches per hour and visibilities under 1/2 mile. The concern is that conditions look similar to what occurred this past Sunday morning over the south half of Chicago and Illinois/Indiana state line and especially Lake County. Uncertainty with the residence time of this band over any specific area remains low, however, with a progressive band or one that goes stationary for a few hours both plausible outcomes. 2 to 4 inches of snow does appear likely for any areas that see the lake effect snow band. If it can stay over one area for long enough period, accumulations nearing 6 inches to possibly exceeding this are still firmly within the realm of possibility. With a fairly sharp cutoff in snowfall amounts expected, far inland areas of Cook and Lake IN counties may only see a dusting, if that. Those out traveling near the lakeshore, including downtown Chicago south along the lakeshore into northern Lake County, IN will need to be prepared for rapidly changing conditions where the lake effect snow band sets up overnight tonight into the Friday morning commute, including the I-90/94 corridor. There are signs in the model guidance that the southern end of the lake effect band trends toward more of a meso-low situation as it recedes back over the lake and pushes eastward. Expect majority of the accumulating snow to end by mid to late morning with lingering lake effect flurries possible into the afternoon. Petr/Castro

Some kind of accident? Very sad news.

NWS is going 12-18" for Boston. I do wonder if ratios may suffer more than Kuchera suggests due to the strong winds. That is a seriously deep low off the coast.

Would suck to be NYC, relatively speaking.

What do we do about the 3km NAM?

iow, the jackpot will either be north or south of downtown

Good news, we still have a storm on the 12z Euro.

Fwiw, apparently we're discussing this in the short/med range thread now.

Kinda miss the old Lake Effect Snow Advisory/Watch/Warning. This certainly would've qualified given no synoptic system in the mix.