Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 190810

Area Forecast Discussion
National Weather Service Northern Indiana
410 AM EDT Sat Aug 19 2017

Issued at 401 AM EDT Sat Aug 19 2017

Scattered showers and thunderstorms will end this morning as a
weak cold front moves to the east. High pressure will build into
the area this afternoon and move slowly east over the rest of the
weekend providing dry weather. As the high moves east of our area early
next week it will become very warm and humid with increasing
chances of showers and thunderstorms. The best chance will arrive
Tuesday as a strong cold front moves southeast across the area.
High pressure will move slowly southeast across the Great Lakes
behind this front, providing fair weather with below normal
temperatures Wednesday through Friday.


.SHORT TERM...(Today and Tonight)
Issued at 401 AM EDT Sat Aug 19 2017

Shrtwv movg east across IL with an attendant wk sfc reflection
causing an area of showers and thunderstorms nrn IN which should
continue to move east across nw OH this morning.  Skies should clear
behind this feature as subsidence/ridging build in allowing temps to
mix out to highs in the lwr 80s, except a little cooler near Lake MI
with onshore flow through the day. Decent radiational cooling
expected tonight with clear skies early and high pressure overhead
providing calm-light s-se winds as it moves east overnight.
Patchy clouds may develop from the w-sw as wk waa begins in wake
of departing high. Expect lows will be in the upr 50s to lwr 60s.
Patchy fog psbl overnight, but confidence on impactful vsby
restrictions too low to add mention to fcst attm.


.LONG TERM...(Sunday through Friday)
Issued at 401 AM EDT Sat Aug 19 2017

Sfc high will continue to move east away from our area Sunday as a
cdfnt drops into the upr Midwest. Moderately increased southerly
low level flow/waa combined with building sern U.S. ridging aloft
should result in mostly sunny skies with temps rising into the
m-u80s in the aftn. Frontal boundary will remain nearly stnry over
the upr Midwest Monday as initial shrtwv moves east across srn
Ontario and stronger upr level trof drops se across Manitoba. This
should result in a mainly dry day with temps continuing to warm
slightly as wk waa and s-sw gradient flow conts. Contd with a
slight chc of tstms n-nw as airmass will likely destabilize and
possibility of convectively induced disturbance movg east in zonal
flow from the plains/mid ms valley. Rain chances increase Monday
night and Tue as strong upr level trof and associated sfc cdfnt
drop se across the grtlks. Wind flow associated with this feature will
be quite strong and moisture abundant, so unless cloud cover/convective
outflows limit destabilization on Tue (which is a possibility),
storms along the front could become svr. Sfc high pressure
expected to move slowly e-se across the grtlks on backside of
amplified upr trof late week, providing fair wx across our area
with blo normal temps.


.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 129 AM EDT Sat Aug 19 2017

Coverage of showers/isolated thunder has been trying to expand
somewhat over past hour or so, but still amounting to no more than
scattered in nature. Current trends suggest precip will remain
just to the south of KSBN, but close enough to hold onto VCSH for
a few hours. Tougher call at KFWA given potential for activity to
die out before reaching there. Opted to remove tempo group
overnight and stick with VCSH. If coverage expands further, then
will amend as needed.

Once this activity departs (after 09-11Z at KSBN and 11-13Z KFWA)
not much going on the remainder of the period with VFR conditions.





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