Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 271040

Area Forecast Discussion
National Weather Service Northern Indiana
640 AM EDT SAT AUG 27 2016

Issued at 114 AM EDT Sat Aug 27 2016

A frontal boundary will keep shower and thunderstorm chances in
the forecast this weekend into early next week. Highs each day
will reach the 80s, with lows in the mid 60s to low 70s.


.SHORT TERM...(Today and Tonight)
Issued at 319 AM EDT Sat Aug 27 2016

S-Swly flow aloft ahead of upr trof movg east across the nrn plains
will advect a very moist airmass back across our cwa today. A couple
of vort maxes over srn/wrn IL causing showers/tstms to our west/sw
which should impact mainly nw portion of our cwa this morning.
Expect this will leave a nne-ssw oriented outflow/differential
heating boundary across the central portion of the cwa upon which
sct convection will initiate this aftn and spread east into more
unstable airmass. Given 00z models indications of deep layer shear
around 30kts overspreading the area today, combined with moderate
instability developing, mainly across e-se portion of the cwa, a
few supercells seem psbl this aftn, and with moist airmass/low
lcls likely, a tornado not out of the question. Warm airmass over
the area should be counteracted somewhat by cloud cover/showers
but temps still expected to be a bit above normal with highs
generally in the m80s. Contd advection of wk disturbances aloft
across our area may cause some convection to cont tonight, but
should grdly wane with loss of daytime heating. Temps will remain
mild with no change in airmass... lows expected in the u60s.


.LONG TERM...(Sunday through Friday)
Issued at 319 AM EDT Sat Aug 27 2016

Flow aloft over our area will weaken Sunday as upr trof moves east
to Quebec and mid Atlantic ridge expands westward into the OH
valley. Wk sfc boundary extending s-sw from the Quebec upr
trof/sfc low should drop south across our cwa during the day and
with airmass remaining moist/unstable may trigger a few tstms over
the area.

Upr ridge will cont building west Sunday night and Monday in
response to deep trof digging s-se off the west coast. Sufficient
lingering moisture/instability/wk sfc boundaries expected to
result in a few aftn tstms, mainly sw. Ridge should cont to
amplify over the nrn plains Tue, allowing shrtwv to drop se across
ontario with associated cdfnt movg across the grtlks psbly causing
tstms in our area. Fair weather with cooler less humid conditions
expected Wed and Thu as post frontal high pressure moves across
the grtlks. Temps should begin to warm Fri as the high moves to
our east and return flow and wk waa develops.


.AVIATION...(For the 12Z TAFS through 12Z Sunday Morning)
Issued at 640 AM EDT Sat Aug 27 2016

Cluster of elevated convection on nose of LLJ across ne IL/far nw
IN may clip KSBN briefly early this morning with a brief
impact/vis restriction. Better chances for a period of
rain/thunder will come later this morning/early aftn at KSBN as
warm front/deeper moisture advect in on se fringe of lead
shortwave lifting into the Western Great Lakes. Diurnal heating
and weak moisture convergence near warm front may generate sct
showers/storms in and around KFWA by this afternoon where a VCTS
mention was retained. Mainly VFR otherwise outside of any
rain/thunder today/this evening across northern Indiana. Any
partial clearing would likely support BR formation later tonight
given ample low level moisture and light winds near sfc front.


.IWX Watches/Warnings/Advisories...



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