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FXUS63 KIWX 111128

Area Forecast Discussion
National Weather Service Northern Indiana
628 AM EST Wed Dec 11 2019

Issued at 353 AM EST Wed Dec 11 2019

Lake effect snow showers and flurries will continue today with 
light accumulations across far northern Indiana and Lower 
Michigan. It will remain cold with highs in the 20s. Warming 
temperatures and dry conditions are then expected Thursday and 
Friday, with chances for rain and snow to follow this weekend.


.SHORT TERM...(Today and Tonight)
Issued at 350 AM EST Wed Dec 11 2019

A weak upper level system with somewhat of a clipper feature will
move across the forecast area today as a weak lake response
continues this morning. Inversion heights will fall today and
bring an end to the lake effect snow as low levels warm. Less 
than a half of an inch of snow is expected from these two systems.
Otherwise, temperatures will remain cold today with highs only in
the 20s. 


.LONG TERM...(Thursday through Tuesday)
Issued at 350 AM EST Wed Dec 11 2019

Return flow will begin on the back side of the high pressure area
Thursday with temperatures rising above normal Friday in the 40s.
An active pattern will set up from Saturday through Tuesday with
upper level energy in the form of short wave trofs moving through
the area. It looks like the first system will bring a good chance
for mainly rain Saturday with rain changing to snow Saturday
night. A second system early next week will bring another round of
precipitation with the chance for accumulating snow.


.AVIATION...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 625 AM EST Wed Dec 11 2019

Cigs have briefly improved at terminals as low level winds have 
slightly backed in advance of next short wave approaching the 
western Great Lakes this morning. A more organized area of snow is
ongoing early this morning across central Illinois where low 
level frontogenesis forcing is maximized. This forcing will 
rapidly shift eastward over the next few hours, but it still 
appears as though stronger vertical motions associated with this 
forcing will remain just south of the terminals. Low level winds 
will veer to west-northwest after midday as this wave passes 
through, and this should provide best chance of MVFR cigs of 2-3k 
feet at KSBN. Some reinforcement of low level thermal trough and 
westerly trajectories should provide KSBN a period of light lake 
snow showers early this afternoon, but this potential should be 
short-lived as the short wave quickly pushes through and rapid 
mid level drying occurs. Steep low level lapse rates today should 
allow for gusts to 15 to 20 knots, but winds should diminish late 
this afternoon and this evening as sfc ridge axis approaches.


LM...Small Craft Advisory until 7 PM EST this evening for LMZ043-046.



SHORT TERM...Skipper
LONG TERM...Skipper

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