Quick update from LOT on a heavy band approaching.
While there could be Advisory-level impacts with this band it
should be on a short time interval. So an SPS has been issued and
a timing graphic will be shortly noting snow coated roads and
sharply reduced visibility. This looks to arrive in the south
Chicago metro around 11-11:30 AM.
This band will slow and expand and become part of the main snow
event this afternoon into tonight. Am growing concerned, similar
to previous shift, that a band could produce significant snowfall
and that may extend into the northern tier of counties in the
CWA. We will continue to analyze forecast data and adapt to
observational trends and conceptual models, and if high enough
confidence, upgrade to a Winter Storm Warning. Also the mixed bag
of precip potential south of I-88 will likely warrant an Advisory.