Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 181436

Area Forecast Discussion
National Weather Service Northern Indiana
1036 AM EDT Sun Jun 18 2017

Issued at 421 AM EDT Sun Jun 18 2017

Showers and a few thunderstorms are still possible today but we
should see a diminishing trend as the day progresses. Partial
clearing is also expected from late morning into the afternoon
hours. While it will be muggy this morning...drier air will arrive
later today helping to lower the humidity. Highs today will reach
near 80 while lows tonight will drop to around 60. There is a
chance of showers and a few thunderstorms on Monday...especially
in the afternoon.


Issued at 1022 AM EDT Sun Jun 18 2017

Forecast generally running on track. Cold front slowly edging east
with back edge of at least partial clearing beginning to move
across western portions of Indiana with much of Lake Michigan now
clear. A few showers continue to pop from time to time across the
area (just had a heavier one here for a period), with this also
expected to continue until frontal passage. have left likely pops
in far SE for a few hours this afternoon as peak heating and
additional lift from both the front and upper level trough help
get things going again. Far SE will be the initiation area at best
for what will probably be another line of strong to severe storms
to impact points east of the area.

Will need to watch temps given strong June sun and at least some
delay in colder air initially for increase in the west.


.SHORT TERM...(Today and Tonight)
Issued at 421 AM EDT Sun Jun 18 2017

Severe threat has ended early this morning with initial wave moving
through the area and increased low level inhibition.
However...modest 30-40kt low level southwest jet along axis of theta-
e ridge aiding in additional shower and thunderstorm development
ahead of main frontal boundary along with gusty sfc winds of 20 to
30 mph. Expect scattered pcpn through 12-14z time frame but
diminishing coverage as LLJ weakens. Additional tsra development
expected from late morning to mid afternoon but likely confined to
our far southeast near frontal boundary with daytime heating as
short wave trough swings through. Satellite shows plenty of clouds
upstream from convective debris. Expect slow clearing trend
through the day but likely hanging onto at least thin high clouds
for transition to partly cloudy this afternoon. Surface analysis
shows upper 60 and even low 70 dew points well to our west and
will take some time for drier air to filter in later today. Highs
will be noticeably cooler reaching near 80 today. Cooler and less
humid air tonight with lows around 60. Hires guidance hinting at
some light showers developing with troughiness aloft over the
area. Not confident on this given low level drying and no strong
forcing so kept tonight period dry.


.LONG TERM...(Monday through Saturday)
Issued at 421 AM EDT Sun Jun 18 2017

Deep trough over the area to start the period with upper low
centered over Ontario. Numerous short wave disturbances expected
through the period as low slowly wobbles into western Quebec
before finally ejecting northeast mid week. Flow will respond by
becoming more zonal across the CONUS late week but models still
show a progressive and active jet with several fast moving short
waves. This leads to a plethora of slight to low chance PoPs in
the extended. Temperatures will be closer to normal this week with
comfortable humidity to begin the week. Warm front and moisture
surge mid week will bring muggy conditions back to the region
along with higher TSRA chances with potential stalled frontal
boundary late week. Will also have to keep an eye on tropical
development and possible moisture flux late week into next


.AVIATION...(For the 12Z TAFS through 12Z Monday Morning)
Issued at 654 AM EDT Sun Jun 18 2017

Some lingering showers and isolated storms are still possible
today; however, chances will be diminishing as the front moves
east. Some wind gust 20-25 knots are possible before the winds
diminish this evening.




SHORT TERM...Lashley
LONG TERM...Lashley

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