1/30-1/31 Lake Effect Snow Threat - SE WI, NE IL, and NW IN

[mimillman]

Looks like gonna crank in a bit 

[IndianaBeachCrow]

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

lots of piss and shit on the block that could use a dusting

[mimillman]

HRRR looking real close 

[homedis]

38 minutes ago, mimillman said:

HRRR looking real close 

Was just looking at that. It really likes the IL/IN border... its gonna be really close for downtown. I don't mind the oscillating if that means more widespread 6-10" rather than one place getting 18".

[ILSNOW]

As per Mike Caplan

The weather service upgrades central and southern Cook county to a winter storm warning. This will include the city of Chicago.

[ILSNOW]

great Ricky update from NWS

As generally anticipated, the mid-level and surface trough axis
configuration today is decidedly focusing lake effect snow
banding near and on the west side of the lake. However, the
intensity of the snow extending well north to offshore of
Manitowoc, WI increases concern for bursts of moderate to heavy
lake effect snow persisting into this evening for northeast
Illinois. While this won`t be a continuous firehose of snow
like in a single dominant intense band, webcams under the
heavier snow rates have consistently shown roads quickly
becoming snow covered/hazardous.

With the previous advisory and watch configuration for central
and southern Cook, there was some thought that there would be
more defined breaks in the accumulating snow, which appears less
likely at this point. Additionally on this note, comparing radar
to recent HiRes simulations, the HRRR seems to have a better
handle than the 12z NAMnest (which initialized too far east with
the snow off the WI shore). This suggests the intense banding
developing this evening has a better chance to impact eastern
sections of Cook County (and possibly even Lake and northern
Cook) before shifting into northwest Indiana tonight.
Ultimately, we opted to just replace the previous advisory for
central and southern Cook with a warning, in effect until
midnight. Confidence isn`t super high in exact trends yet, but
felt that localized 6"+ amounts appear quite likely (especially
near the lake), and more importantly the significant impacts to
travel due to periods of 1-2"/hour snow rates and visibility as
low as 1/4 mile.

We`re keeping a close eye on webcams and road conditions in
Lake and northern Cook as well (Waukegan Airport 1/4 mile
visibility as of this writing) for a possible need to upgrade
these counties from an advisory to a warning. As the snow
band(s) come ashore today, convective snow showers may spread
fairly far inland into areas where broad light snow is ongoing
underneath the mid/upper trough. Should it appear this activity
is more potent, we may need to consider advisories for this, or
at least Special Weather Statement issuance. The Winter Storm
Warnings for Lake and Porter County Indiana remain unchanged for
now. DuPage County IL is also in an advisory given the closer
proximity to the lake of northeastern sections of the county,
though again, confidence is on the lower side regarding how
things will play out farther inland in the Chicago suburbs.

 

[btcs31]

1 hour ago, homedis said:

Was just looking at that. It really likes the IL/IN border... its gonna be really close for downtown. I don't mind the oscillating if that means more widespread 6-10" rather than one place getting 18".

That's me! LES here is usually transient as it's passing from west side of the lake to southeast. Tough to get a prolonged band aimed S/SW. Expectations are tempered but nice seeing the WSW extended to my west.