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fxus63 kiwx 261022 

Area forecast discussion
National Weather Service northern Indiana
622 am EDT Wed Jun 26 2019

issued at 400 am EDT Wed Jun 26 2019

Chances for mainly afternoon and evening showers and storms
will persist through this weekend. Strong, gusty winds, locally
heavy rain and small hail are possible with the strong storms each
day. The best chances for storms today will be near and south of
Highway 30. Conditions will become more humid starting Thursday
with afternoon heat indices in the low to mid 90s.


Short term...(today and tonight)
issued at 357 am EDT Wed Jun 26 2019

A cluster of storms that was over Illinois last night has almost
totally dissipated with a few remaining high based showers over
northern Indiana. This system has produced a large outflow
boundary that has pushed well to the east of the earlier storms.
Storms are possible mainly south of Highway 30 with daytime
destabilization of the lower layers. Not much in the way of shear,
but afternoon convective available potential energy should top 2000 j/kg and downdraft convective available potential energy may
reach close to 1800 j and provide chances for strong gusty winds
that could reach severe levels. Hail is also possible, but appears
to be a smaller potential.


Long term...(thursday through tuesday)
issued at 357 am EDT Wed Jun 26 2019

An active pattern will persist through Sunday as very humid
conditions develop. Precipitable water values will generally range
from 1.5 to 1.9 inches topping the 90th percentile for this time
of year over northern Indiana and nearby areas. Shear values will
remain relatively low, but downward cape values will become very
high during the afternoon indicating the chances for gusty winds
possibly reaching severe levels each day. Also, locally heavy rain
is possible each day through Sunday. Concern with 4 days of heat
indices in the low to mid 90s following a Cool Spring. Plan to
highlight these concerns in the hazardous weather outlook product.
Otherwise, it looks like about the only dry period at this point
will be Sunday night into Monday.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 620 am EDT Wed Jun 26 2019

VFR conditions are expected to prevail this forecast valid period
with main item of uncertainty on convective potential this
afternoon into this evening. Weak low level front settling across
the Great Lakes region will provide a south to north instability
gradient this afternoon, with more unstable conditions anticipated
at kfwa. Forcing remains the big question with an overall lack of
significant synoptic scale forcing. May need to watch for the
possibility of convectively enhanced disturbance moving out of
south central Iowa this morning which could allow for some
afternoon/early evening enhancement to scattered showers/storms
across northern Indiana. Given relatively unstable conditions will
include a thunderstorms in the vicinity mention at kfwa in the 21z-01z timeframe, but
confidence in coverage remains on the lower side. West-southwest
winds of 10 knots or less are expected today with a possibility of
brief northwest component later in the afternoon at ksbn due to
marine influence. Expecting any scattered showers and storms to
exhibit preference to peak heating/evening hours, and will keep
remainder of tafs dry for most of tonight.


Iwx watches/warnings/advisories...


short term...skipper
long term...skipper

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