Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 270730

Area Forecast Discussion
National Weather Service Northern Indiana
330 AM EDT Tue Sep 27 2016

Issued at 330 AM EDT Tue Sep 27 2016

Sunny and breezy conditions can be expected today before a low
pressure system brings clouds, chances for showers, and cool
temperatures to the area later tonight through Saturday. Highs
today will generally reach the upper 60s to near 70 degrees. Lows
tonight through the weekend will range between the upper 40s and
mid 50s, with afternoon highs in the 60s.


.SHORT TERM...(Today through Wednesday)
Issued at 330 AM EDT Tue Sep 27 2016

Dry westerly flow will persist locally today under
filling/vertically stacked Lake Superior low. Ample solar
insolation and deep mixing on the southern fringe of this feature
should drive gusty wind to near 25 knots by late morning/afternoon
and a decent temp recover close to average.

Deep low will drop south along Lake MI tonight and into northern
Indiana tomorrow. The low level diabatic response over southern Lake
MI will aid to strengthen the low level circulation/troughing into
far nw IN/sw Lower MI later this evening through early Wednesday
afternoon. This convergence/moisture flux should help focus more
widespread heavier showers (iso thunder?) into sw Lower MI and far
nw Indiana during this time. Lower shower chances will extend into
the rest of the forecast area on Wednesday as PV/theta-e push pivot
through with vort lobe.


.LONG TERM...(Wednesday Night through Monday)
Issued at 330 AM EDT Tue Sep 27 2016

The last several model cycles have come around to the solution the
ECMWF introduced 3 days ago in the upper low cutting off southeast
into the TN/OH Valleys Wednesday night into Thursday, then slowly
wobbling back north through the Great Lakes by this weekend. Clouds,
cool temps, and periodic chances for rain will be the result as
multiple upper waves rotate through around the periphery of the low.
Areas of rain Thursday into Friday will likely focus within
deformation/warm conveyor belt across the lower/eastern Great Lakes,
with the precipitation pattern trending more diurnally
driven/scattered by Saturday under the upper low. There may also be
just enough heating under cold pool aloft to generate a few
afternoon (non severe) storms Thursday through Saturday, though
point chances remain too low for a slight chance thunder mention at
this fcst range. Improvement is then expected by early next week as
negative height anomaly finally gets ingested back into westerlies.


.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 103 AM EDT Tue Sep 27 2016

VFR conditions will persist through this period yet big changes in
store thereafter. Insolation will again drive strong wswly gusts by
late morning through late afternoon...sfc gusts aoa 25 knots.


LM...Small Craft Advisory until 11 PM EDT Wednesday for LMZ043-046.



SHORT TERM...Steinwedel
LONG TERM...Steinwedel

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