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Area forecast discussion 
National Weather Service northern Indiana
759 PM EDT Friday Apr 17 2015

issued at 755 PM EDT Friday Apr 17 2015

Quiet warm weather will continue tonight and Saturday. Skies
overnight will be mostly clear to partly cloudy. Lows will be in
the upper 40s to around 50. Though clouds will gradually increase
during the day Saturday...highs will reach into the middle to
upper 70s. Rain is expected on Sunday...with isolated
thunderstorms possible.


Short term...(this evening through saturday)
issued at 419 PM EDT Friday Apr 17 2015

A quiet short term period with high pressure centered over the
region providing light winds and generally clear skies. Fog from
this morning has burned off as expected with diurnal heating and
mixing. A patch of middle level clouds have drifted into far northwest County Warning Area
early this afternoon. Expect these to thin but model soundings
have been hinting at some lingering middle level moisture through
the night into Saturday. Not enough to really derail mostly clear
forecast but a few hours of scattered or broken middle level clouds as we are
currently seeing remain possible. Otherwise dry with light winds
becoming more easterly on Saturday as low level flow veers ahead
of approaching short wave for Sunday.

Low temperatures tonight should remain in the 50s most areas with some
upper 40s possible...especially east. Another mild Spring day in
store for Saturday with temperatures back into middle 70s and will again
side toward higher end of guidance envelope given recent


Long term...(saturday night through friday)
issued at 419 PM EDT Friday Apr 17 2015

An upper low over the southwest Continental U.S. Will lift northeast and
merge with a northern stream upper level trough Saturday night over
the Central Plains. This system will then move east into the
forecast area Sunday and Sunday night. Moisture flux will
increase rapidly ahead of this system...with precipitation water values
approaching 1.50 inches...which is close to the 99th percentile
for this time of year according to climatology. the
warm front lifts north... substantial low level shear will spread
over the area. 0-3km helicity is forecast to exceed 1000 m2s2
with nearly 50 M/S shear in this layer...although the NAM is
indicating little if any cape. Believe this situation still needs
to be watched given the potential for supercells producing strong
to severe storms.

Otherwise...cooler air will return to the area next week. Kept
lows well down into the 30s Tuesday night through Thursday night.
Frost is likely one or more nights. Tempered superblend chance
probability of precipitation to mainly dry for this upcoming work week based on office
verification showing a profound wet bias and given only weak
systems moving through the area.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 755 PM EDT Friday Apr 17 2015

High pressure to assure VFR met conds through the period. Xover temperatures
down into the lower 40s across northern in to preclude early am br/fog
formation as well.


Iwx watches/warnings/advisories...


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

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