Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 281751

Area Forecast Discussion
National Weather Service Northern Indiana
151 PM EDT THU JUL 28 2016

Issued at 136 PM EDT Thu Jul 28 2016

Showers and thunderstorms are possible this afternoon and
overnight, especially west of I 69. Severe weather is not
expected, but locally heavy rain is possible with any
thunderstorms. Highs will reach into the lower to middle 80s with
overnight lows in the middle 60s.


.SHORT TERM...(Today and Tonight)
Issued at 328 AM EDT Thu Jul 28 2016

Through 8 am...Thunderstorm has recently developed south of
Milwaukee drifting slowly east. Isolated showers/storms had also
formed earlier over southern Lk MI in what appears to be an area
of weak convergence. Widely scattered light showers also have been
attempting to move slowly NE out of central Indiana into far SE
areas on nose of increased Theta-E. These have been weakening as
they move closer and away from better moisture. Can`t rule out a
touch of rain occurring but not worthy mention in zones at this

After 8 am...Slowly increasing surface dewpoints will continue to
advect in today with mid to possibly upper 60 dewpoints possible.
This combined with temperatures in the 80s will allow for a weakly
unstable uncapped atmosphere will be in place as a disturbance
drops out of SE Minnesota into the Great Lakes during peak
heating. The wave will push a weak surface boundary south
providing a limited focus for widely scattered to scattered
showers and storms. This front was responsible for a line of
storms across central Lower Michigan yesterday with a outflow from
it meeting its demise somewhere over the forecast area this past
evening. Given these details...think the 30 to 40 percent pops are
warranted across the northern portions of the area into the
afternoon with the chances likely focusing more across central and
southern areas during the evening (maybe overnight) hours tonight
as the front continues south. No concerns for severe weather as
little in the way of shear exists with 0-6 km bulk shear barely
reaching 15 kts but this same weak flow will set the stage for
slow moving storms that may drop a good deal of rain in some


.LONG TERM...(Friday through Wednesday)
Issued at 328 AM EDT Thu Jul 28 2016

Challenges will reside with impacts of increasing upper level
ridging through the first half of the period (into Monday)
followed by flattening of the ridge as a series of stronger waves
move out of the Plains.

Frontal boundary will reside not to far from the area with
lingering chc pops in SW sections Friday and eventually across all
areas into Saturday. Dry period looks to be on tap Sat Ngt into
Monday night as ridging pushes axis of precip north and slowly
increase heat and humidity towards mid week. As noted
above...ridge may break down some and allow "Ring of Fire" to come
back into the area towards the end of the period. Superblend leans
towards mid to even high chc pops in this period but given
concerns on location of ridge and timing of waves...collaboration
resulted in lowering to slgt chc pops for most offices.


.AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 136 PM EDT Thu Jul 28 2016

Scattered/isolated showers and thunderstorms are expected within
the first portion of the TAF period, with the best chances at KSBN
this afternoon/evening. Still uncertain as to how far east the
showers/storms will develop overnight, but kept the going mention
of rain showers in the KFWA TAF starting around 02Z. As of 1740Z,
light rain showers were developing in Berrien/Cass MI counties,
just north of SBN. Otherwise, expecting VFR conditions to prevail
through the period, with intermittent drops to MVFR in heavier
rain showers/storms. Some of the guidance suggests IFR/MVFR
visibilities at KFWA late tonight/Friday morning-but was not
confident enough to include in this TAF issuance.


.IWX Watches/Warnings/Advisories...


LONG TERM...Fisher

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