Area Forecast Discussion
Issued by NWS Chicago, IL

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FXUS63 KLOT 191827

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
127 PM CDT Mon Mar 19 2018

127 PM CDT

Through Tuesday...

Breezy east-northeasterly winds are expected to continue through
the period as low pressure tracks eastward well south of the area
and high pressure remains dominate over Ontario tonight into
Tuesday. This northeasterly flow will transport a colder airmass
over the area for Tuesday resulting in cooler high temperatures
area-wide. High temperatures Tuesday are expected to be in the
low to mid 40s well inland, but likely only in the mid to upper
30s closer to the lake under partly cloudy skies. Conditions will
feel even cooler than these values, however, as winds continue to
gust up to 25 to 30 mph during the day.



348 AM CDT

Tuesday through Sunday...

Blustery conditions should continue through Tuesday as northeast
winds continue with highs ranging from the middle 30s across nern IL
to the lower 40s well inland.  Some moderation for much of the area
is expected for midweek as a ridge of high pressure extends from
Hudson Bay to along the Mississippi River.  However, persistent flow
off of Lake Michigan should keep lakefront locations a bit cooler
than inland areas.  The next significant chance for precipitation is
still not expected until Friday and through the weekend.  The longer
range guidance remains consistent in amplifying the upper level
pattern by the end of the week, with an area of low pressure quickly
tracking across the Central Plains late Friday.  However, there are
still significant differences among the models as to the exact track
and intensity of the system into next weekend.  The general model
consensus at this point does indicate the decent potential for
precipitation as a mid-level shortwave tracks across the region, the
models diverge significantly on the track of the associated surface
low moving through central IL. IN general, thermal profiles
generally support rain or a rain/snow mix across the area, with the
greatest potential for any snow occurring during the diurnally
cooler nighttime periods.


For the 18Z TAFs...

There are no major weather concerns at the terminals through the
period. Overall, expect VFR conditions with gusty east-
northeasterly winds through the period as low pressure tracks
eastward south of the region.



115 AM CDT

Northeast times more due north or due east...will
prevail across Lake Michigan through the entire week.

Speeds will be on the increase early this morning as the lake
finds itself between strong high pressure to the north and passing
low pressure well to the south. Small Craft Criteria winds and
shortly after waves are expected to develop along the Illinois
shore this morning and Indiana shore by mid-afternoon. The
highest wind and wave time in the Illinois and Indiana nearshore
looks to be tonight and Tuesday during the day. This will be a
fairly long lasting event, with gusty winds and high waves
lasting through Wednesday morning, and probably some 3-5 ft waves
lingering even longer into Wednesday.

Another low pressure is expected to move eastward across the
middle of the country, likely south of the lake, late in the
week/early weekend. This again will strengthen east or northeast



LM...Small Craft Advisory...IN nearshore waters until 9 AM Wednesday.

     Small Craft Advisory...IL nearshore waters until 9 AM Wednesday.




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