Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 190526

Area Forecast Discussion
National Weather Service Northern Indiana
126 AM EDT Thu Oct 19 2017

Issued at 745 PM EDT Wed Oct 18 2017

High pressure will remain across the region through Saturday and
will maintain dry and mostly clear conditions. Low temperatures by
daybreak Thursday will be in the upper 40s to lower 50s, with
afternoon highs reaching into the upper 60s to middle 70s, but a
bit cooler near Lake Michigan on Thursday. The next chance of rain
will arrive on Sunday.


.SHORT TERM...(This Evening through Thursday)
Issued at 340 PM EDT Wed Oct 18 2017

No sensible weather concerns through the short term as behemoth
ridge and associated dry/stable airmass remain entrenched over the
eastern CONUS through Sat. High latitude trough/front will pass to
our north overnight and this will maintain a decent gradient
overnight and may support some high clouds in the morning. Main
impact of this will be milder lows tonight. Some slight warm/moist
air advection ahead of this front and persistent gradient should
keep lows in the upper 40s/around 50F. Postfrontal CAA is minimal
and confined to Michigan. Highs may be a little cooler near the lake
with weak W/NW flow but still mid 60s there and low 70s in our
south. Expect sunny skies by afternoon.


.LONG TERM...(Thursday Night through Wednesday)
Issued at 340 PM EDT Wed Oct 18 2017

Ridge rebuilds aggressively late tomorrow into Friday as next
Pacific trough crashes into the western CONUS. Dry and sunny
conditions will persist on Friday with highs creeping into the mid
70s. A few more clouds possible by Sat but WAA/SW flow also
increases with another day in the mid 70s.

Forecast for Sunday and Monday still uncertain with Canadian and,
to a lesser extent, the 12Z ECMWF indicating a much slower/more
closed off solution. GFS and majority of its ensemble runs remain
much more progressive, similar to the 00Z ECMWF. Maintained likely
PoPs on Sunday with good CVA and theta-e advection ahead of the
front. Not enough instability to introduce thunder mention but
could see some modest (around 0.25 inches) rainfall. Forecast
confidence decreases drastically for Monday and stayed close to
concensus PoPs for now. Secondary trough digs into the Great Lakes
but question is whether or not it will arrive quick enough to
phase with lingering wave to our south. Regardless, do expect
colder temps and persistent rain chances for the middle of next


.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 122 AM EDT Thu Oct 19 2017

VFR conditions through the period with only near term concern
being marginal low level wind shear, mainly at KSBN. KIWX 88D
showing 40 kt winds just off the surface so will stick with
previous mention.


LM...Small Craft Advisory until 4 AM EDT early this morning for




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