Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 271753

Area Forecast Discussion
National Weather Service Northern Indiana
153 PM 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.


Issued at 950 AM EDT Sat Aug 27 2016

Minor update to increase POP`s and QPF for late this morning and
into the afternoon. Plume of rich low level moisture is currently
moving north along with weak/embedded shortwave. This is
supporting numerous showers and storms and latest hi-res CAM`s
indicate this activity will continue through most of the day.
Potential for some brief heavy rain and minor/isolated flooding
in our northwest given PW values over 2 inches. A few of these
storms could also produce damaging wind gusts, especially in our
SE this afternoon where better instability will be allowed to
build, but threat for widespread severe weather is low. Tornado
threat also appears low given only modest low level shear and
disconnect between lower LCL`s in the west and better instability
in the E/SE.


.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 18Z TAFS through 18Z Sunday Afternoon)
Issued at 141 PM EDT Sat Aug 27 2016

Embedded short wave and axis of enhanced deeper moisture has
allowed for showers and storms to fill in across northwest Ohio.
Greater chances of showers and thunderstorms have shifted east of
the terminals in the near term. Some instability recover is
expected this afternoon, particularly across northwest/north
central Indiana. However, with primary short waves having worked
north and east of the terminals, confidence is low on additional
showers and storms impacting point terminal locations. Otherwise,
have continued mention of fog tonight with lingering low level
moisture and light flow. Trended TAFS to IFR in the 09Z-12Z
timeframe, with some possibility of LIFR conditions depending on
extent of stratus. VFR conditions expected for the remainder of
the forecast period after any patchy fog diminishes early Sunday


.IWX Watches/Warnings/Advisories...



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