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Area forecast discussion 
National Weather Service northern Indiana
647 am EDT Wednesday Jul 29 2015

issued at 305 am EDT Wednesday Jul 29 2015

A weak front will pass through the Great Lakes today bringing
the chance for a few showers and thunderstorms...mainly this
afternoon. Highs will range from lower 80s near Lake Michigan to
the upper 80s in Northwest Ohio.


Short term...(today and tonight)
issued at 305 am EDT Wednesday Jul 29 2015

Potent SW disturbance over southern mb will carry northeastward into
James Bay by Thursday am as trailing surface boundary washes out across the lakes
this afternoon. Downstream ll follow within eastward folding ll Theta-E ridge
however remains weak west/850 mb wrly winds of 15kts or less. Thus in
combination west/eastward stream of conv cloud debris through this morning and
general poor frontal based forcing as associated height falls west/SW pass well
north. All the more reason to back off on probability of precipitation especially western portions
early on even in light of recent conv cluster across NE Illinois which is
expected to decay eastward into far Northwest Indiana prior to sunrise. Meanwhile
most agreeable short term guidance suggests some isolated-scattered storm
development plausible after 18z in eastern areas...I-69 east and generally


Long term...(thursday through tuesday)
issued at 305 am EDT Wednesday Jul 29 2015

Upper level low currently moving northeast through the plains will
head towards Hudson Bay and remain in the general area through much
of the extended period. Series of waves will rotate through the flow
and make headway towards the Great Lakes every few days. Best focus
for chances appears to be in the Sunday to Monday time frame when
plume of moisture moves in ahead of a slightly more pronounced wave to
give somewhat better chances for measurable rain. Grids generally
left alone with models continuing to flip flop on timing/location of
best chances.

Temperatures will remain seasonable in the lower to middle 80s for
high through much of the period.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 645 am EDT Wednesday Jul 29 2015

VFR conds expected through this period. Little change from prior thinking with respect to
weakly forced frontal boundary that will push across the terminals this
afternoon. However based on near term hrrr trends and expected upstream decay of
NE Illinois mesoscale convective system...delayed mention at kfwa a bit later.


Iwx watches/warnings/advisories...


short term...T
long term...Fisher

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