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Area forecast discussion 
National Weather Service northern Indiana
610 am EDT sun Sep 21 2014

issued at 327 am EDT sun Sep 21 2014

A strong cold front will sweep east across the area early this
morning...ushering in much cooler air along with gusty northwest
breezes. A disturbance aloft will cross the area this afternoon
and may give rise to a few light showers. High temperatures will be
in the low to middle 60s.


Short term...(today and tonight)
issued at 327 am EDT sun Sep 21 2014

Pv anomaly associated/west intense SW over northern WI will dive rapidly southeastward
into northern in by midday as lg scale middle level trough amplifies sharply
southeastward. Surface cold front in association/west this system extends from Western Lake Michigan southwestward into
central in and will clear eastern County Warning Area by daybreak. Southern flank of convn
along this ftr will carry eastward through southern Michigan otrws scattered rain showers/thunderstorms and rain
continue to fester within downstream warm air advection overtop left over outflw
bubble from convn last evening yet on the way out over far southeastern zones.
Again though expect all of this will be east of County Warning Area by sunrise and
will then await arrival of middle level trough across the northwest County Warning Area toward the
noon hour followed by rapid southeastward pivot through middle afternoon.

Post frontal airmass gets gutted as strong cold air advection Wing drives southeastward through
this morning. Paltry left over residual ll Theta-E in combination
west/innocuous vertical ascent warrant tempering probability of precipitation as reflected
both in MOS trends and seen in nearly all highres solutions.

Temperatures will be sharply colder vs yesterday/S unseasonably warm readings
west/highs in the low to middle 60s. Surface ridge builds east overnight west/clearing
and will follow colder side of MOS guidance.


Long term...(monday through saturday)
issued at 327 am EDT sun Sep 21 2014

Little to talk about for the long term as high pressure will drift
across the region through Tuesday before parking to the east for the
remainder of the week into the weekend. Coolest temperatures will be seen
Monday into Monday night given proximity of ridge axis. Morning lows
Monday will be in the lower 40s with temperatures rebounding only
into the 60s and then back down into the middle 40s Monday night.

From Tuesday on...slow moderation will take place with highs
reaching into the lower to middle 70s and no signs of rain.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 609 am EDT sun Sep 21 2014

Leading edge of vigorous ll cold air advection Wing now overspreading northwest County Warning Area and
will rapidly sweep southeastward through County Warning Area by middle morning. Robust rise/fall
couplet yielding fairly gusty Post frontal nwrly winds west/gusts up to
30kts noted in 10z observation.

Upstream rain showers in association/west SW wrapping up across eastern WI and underneath
middle level cold pocket will generally clip far NE portion of County Warning Area toward
lt morning. Trailing vorticity lobe and weak ll forced ascent may yield a
sprinkle/light rain showers at the terminals early this afternoon but will again
defer any mention as little if any sensible impact expected. Primary
aviation hazard going forward will be escalation of surface gradient especially after
sunrise underneath middle level dryslot. Lamp guidance continues to uptick
slightly higher west/nwrly surface gusts above 25kts for a time likely from middle
morning through middle afternoon.


Iwx watches/warnings/advisories...
Lm...Small Craft Advisory until 1 PM EDT Monday for lmz043-046.



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

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