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Area forecast discussion 
National Weather Service northern Indiana
633 am EDT Tuesday Jul 7 2015

issued at 332 am EDT Tuesday Jul 7 2015

Showers and scattered thunderstorms are expected to accompany a
strong cold front as it moves across the area today. High
temperatures are expected to range from the upper 60s near Lake
Michigan to the lower 80s over southeast portions of the area...
however it will be turning cooler over the entire area by late
afternoon. Scattered showers and a isolated thunderstorms may
linger tonight over southern portions of the area as the cold
front stalls over southern portions of Indiana and Ohio. Lows
tonight are expected to range from the middle 50s northwest to the
lower 60s southeast.


Short term...(today and tonight)
issued at 332 am EDT Tuesday Jul 7 2015

Strong cold front extends from northern Michigan to SW MO with a band of showers
and scattered thunderstorms along the frontal boundary. This front is expected
to move east into northwestern portion of the County Warning Area by 12z and move east
across the remainder of the County Warning Area by this evening. Given very moist
airmass and strong forcing along the front... expect widespread
showers and scattered thunderstorms will accompany it as it moves across our
area today. Pwat's in excess of 2" and warm cloud layer depth
>12kft suggests some locally heavy rainfall possible. High temperatures
should come early this morning northwest and early this afternoon southeast as
showers followed by cold air advection overspread the area. Expect highs to range
from the M-u60s near Lake Michigan to the l80s southeast. Moderate
instability may develop briefly over the southeastern portion of the County Warning Area
by midday before widespread showers move in. Lack of significant deep
layer shear and only modest wind fields suggests storms will be
marginally severe at worst with gusts 40-50mph. Some showers may
linger across southern portions of the area tonight as the cold front
becomes parallel to middle level flow and stalls over the Ohio Valley
with weak shrtwv's moving east-northeast along it. Temperatures will be considerably
cooler than Monday night with lows ranging from the m50s northwest to the
l60s southeast.


Long term...(wednesday through monday)
issued at 332 am EDT Tuesday Jul 7 2015

Period of stable/dry conditions Post-frontal into Wednesday appears
somewhat brief as respectable low amplitude shortwave aided by
convection and right entrance region upper jet support propagates
through later Wednesday-early Thursday. Resulting surface frontal
wave/deformation and compact corridor of deep moisture convergence
looking more likely to produce a soaking rain Wednesday night. Rain
chances quickly diminish on Thursday in wake of this system as temperatures
remain cool for middle July standards.

A southeast Continental U.S. Upper ridge will build/retrograde toward the south-
central US Friday into this weekend. Associated slight increase in
middle level heights locally will allow more typical July heat/humidity
to return...but with this will come periodic shower/storm/MCS
chances as Theta-E/instability gradient oscillates between the lower
lakes and Ohio Valley on the northern fringe of the upper ridge.


Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 629 am EDT Tuesday Jul 7 2015

Cold front moving through NE Illinois should pass sbn around 14z and FWA around
18z. Widespread rain showers and scattered thunderstorms and rain were occurring along/ahead of the
front and should impact both terminals today. Mainly MVFR
conditions occurring and expected this morning ahead of the front...
lowering to IFR behind it. Sbn expected to improve to VFR this
afternoon while Post frontal IFR should persist into this evening at FWA
as front slows down and eventually stalls out over the Ohio


Iwx watches/warnings/advisories...
in...beach hazards statement through this evening for inz003.

Michigan...Beach hazards statement through this evening for miz077.

Lm...Small Craft Advisory until midnight EDT tonight for lmz043-046.



short term...jt
long term...steinwedel

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