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FXUS63 KIWX 231958

Area Forecast Discussion
National Weather Service Northern Indiana
358 PM EDT Mon Oct 23 2017

Issued at 325 AM EDT Mon Oct 23 2017

A soaking rain will continue into this evening. Rainfall amounts 
of 2 to 4 inches can be expected over far southwest Lower Michigan
into northwest Indiana, with much lower amounts elsewhere. 

Tuesday into Wednesday with feature much cooler conditions and
additional chances for rain showers under deep low pressure over
the Great Lakes region. Highs both days may struggle to get out 
of the 40s. A brief shot of warm and dry conditions into Thursday 
will be followed by another surge of cool air Friday into the 


.SHORT TERM...(This Evening through Tuesday)
Issued at 355 PM EDT Mon Oct 23 2017

The main deformation zone has set up farther west then earlier 
anticipated. The far northwest part of the forecast area from 
Laporte to western Berrien county had received 2.0 to 3.5 inches of 
rain during the past several hours. After coordination, have issued 
a flood advisory for this area. The low pressure area will rapidly 
deepen and move north tonight, with the heaviest rain shifting north 
of the area. The low should drop below 980 mb by daybreak. More 
showers should spread back into the area Tuesday as impulses rotate 
around the main low and as delta T values increase and favor lake 
enhanced showers. 


.LONG TERM...(Tuesday Night through Monday)
Issued at 355 PM EDT Mon Oct 23 2017

Much colder air will spread across the Upper Great Lakes region into 
Wednesday as showers end by late in the day. High temperatures will 
only be in the 40s Wednesday. After a short dry period from 
Wednesday night through Thursday night, another round of showers is 
expected followed by more colder air for this weekend. Kept chilly 
lows close to freezing from Friday night through Monday morning. A 
light rain/snow mix is possible, but no snow accumulations are 


.AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon)
Issued at 122 PM EDT Mon Oct 23 2017

Surface low pressure beginning to rapidly deepen as it lifts
northeast across the area. Developing dry slot will bring a brief
end to moderate rain at KSBN but improved flight conditions will
not arrive until flow backs to a more westerly direction. VFR
conditions will be possible at KSBN during this time but return to
IFR expected by late tonight as CAA ramps up. Deteriorating
conditions expected at KFWA as cooler/more moist air advects into
the area. A period of IFR is possible this evening but held just
above for now given low confidence. Some improvement then expected
overnight but will still likely be hovering around fuel alternate


LM...Gale Watch from Tuesday afternoon through late Tuesday night for 

     Small Craft Advisory until 2 PM EDT Tuesday for LMZ043-046.



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

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