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FXUS63 KIWX 210742

Area Forecast Discussion
National Weather Service Northern Indiana
340 AM EDT Mon Oct 21 2019

Issued at 340 AM EDT Mon Oct 21 2019

A band of showers will overspread the area late morning into early 
aftn followed by showers and a few thunderstorms this afternoon into 
early evening along a strong cold front. In addition, strong south to 
southeast winds will overspread the area with gusts to 40 mph likely 
this afternoon. Highs will range from 65 to 70.

Much colder and continued windy tonight and Tuesday.


.SHORT TERM...(Today through Tuesday)
Issued at 340 AM EDT Mon Oct 21 2019

Upstream expanding precip shield over MO advancing rapidly newd and 
will spread into swrn areas mid morning and into nw OH by early 
aftn. A period of strong/gusty winds likely to arise on backside of 
this activity per intense mixing within maxmized low level jet core 
late morning through mid aftn.

Thereafter some recovery likely ahead of strong sfc cold front this 
aftn. Cams solutions remain adamint on low topped convection 
developing along cold front w/some suggestion of a thin line event 
late through nrn IN which within a very strong kinematic wind field 
would pose some certain svr wind risk. 

Otherwise robust low level cold advection follows overnight and 
Tuesday with gusty post frontal swrly flow expected. Passage of 
moist/trailing mid level trough likely to support additional showers 
north by late morning through mid aftn and bumped pops a bit higher 
per good consensus signals.


.LONG TERM...(Wednesday through Sunday)
Issued at 340 AM EDT Mon Oct 21 2019

Perturbed/active NOAM flow continues this period. Next progressive 
sw disturbance digging through highly amplified flow will spurn 
additional showers Thu into Friday within over running flow atop low 
level baroclinic zone through the srn lakes/wrn OH valley. Lots of 
deterministic noise in this time frame yet ensemble clustering 
warrants holding close to prior mid range chance pop mention.

Greater disparity seen thereafter for next weekend. Some proclivity 
for lagging jet/sw distubance to break off through the srn plains 
and spin up another sig cyclone that lifts out through the OH valley 
as indicated by similar multi-run trends of the EC/GEM. GFS and most 
ensembles contrast with a much more progessive open/weaker sys 
aloft. Nevertheless will hold with some mention of pops late 
Sat/early Sun attm.


.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 207 AM EDT Mon Oct 21 2019

VFR conditions will deteriorate to MVFR/IFR through the period as 
the occluding low pressure system over the northern plains lifts 
into MN/WI/Upper Michigan. This period we deal with the initial push 
of Warm air/moisture advection ahead of the occlusion, with the warm 
front lifting north over the terminals through tomorrow, and the 
cold front to the west impinging in rapidly behind. We'll see rain 
and maybe even a few thunderstorms during the 15-00z time frame. 
Expect some improvement after 00z/3z (west to east) as the dry slot 
moves in. 


LM...Small Craft Advisory from 11 AM Monday to 11 AM EDT Tuesday for 

     Gale Warning from 11 AM to 11 PM EDT Tuesday for LMZ043-046.




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