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FXUS63 KIWX 201142

Area Forecast Discussion
National Weather Service Northern Indiana
642 AM EST Wed Nov 20 2019

Issued at 330 AM EST Wed Nov 20 2019

Cloudy skies will persist today although some late day sun may peak 
through in spots. Highs will reach into the low to mid 40s. Milder 
temperatures and periods of light rain will follow Thursday and 
Thursday night as low pressure tracks through the Great Lakes 


.SHORT TERM...(Today and Tonight)
Issued at 330 AM EST Wed Nov 20 2019

Moisture trapped beneath fairly sharp subsident inversion aloft will 
keep pesky clouds in place today although some late aftn decay 
southwest likely. Nonetheless this combined with weak boundary layer 
mixing in association with sfc ridge crossing the area point to 
preferred cooler side of guidance temps.

Thereafter warm advection ramps expeditiously overnight ahead of 
lead piecemeal sw disturbance ejecting out of the great basin up 
through the upper midwest. Slowed ewd arrival of mentionable pops 
til aft 09Z and confined to far west per strong multi-model 


.LONG TERM...(Thursday through Tuesday)
Issued at 330 AM EST Wed Nov 20 2019

Light rain along prefrontal trough will overspread the area Thu 
followed by weak post frontal cold advection Fri. 

Trailing parent great basin low kicks out Fri through the plains and 
then ewd through the ern OH valley Sat. Similar EC/GFS solution 
aloft from 00Z with track of upper wave yet mixed ensemble guidance 
wavers further south similar to prior deterministic guidance. 
However this bears scrutiny as some mixed phase potential exists 
along nwrn flank of the precip shield late Sat. Seasonably cool/dry 
wx follows Sun-Tue.


.AVIATION...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 632 AM EST Wed Nov 20 2019

The center of a surface high pressure area was near the Ohio 
River and drifting southeast over the region as a rather stagnant 
pattern continued over northern Indiana where moisture and clouds 
remained trapped under a strengthening subsidence inversion. Some 
light/MVFR fog should mix out by mid morning. Still pessimistic 
about much clearing later today given the strength of the 
inversion and the unlikelihood of the lower layers being able to 
mix out given the strength of the inversion and given limited 
insolation for this time of year. However, it does look like 
clouds bases should be mainly VFR so have FWA ceilings staying VFR
and SBN becoming VFR as bases rise above 030 by early afternoon.


LM...Gale Watch from Thursday morning through Thursday evening for 




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