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Area forecast discussion 
National Weather Service northern Indiana
647 am EDT Thu Oct 27 2016

issued at 257 am EDT Thu Oct 27 2016

Cloudy skies and cool temperatures expected today as low pressure
lifts out across the eastern Great Lakes. Highs today will range from
the upper 40s over south central Michigan to the mid 50s over
central portions of Indiana and Ohio.


Short term...(today and tonight)
issued at 257 am EDT Thu Oct 27 2016

Cold front associated with SW disturbance cutting through nrn
lower Michigan lagging back across NE Illinois/NW in yet will accelerate ewd
through daybreak as system lifts out through the ern lakes.
Prefrontal trough still continues to drive sct shower development
over ern third of County Warning Area although with a diminishing trend as low
level jet and attendant moisture flux shift east out of NW Ohio by
daybreak. Thus will drop prior lingering pops across the east
after daybreak.

Otherwise shallow but intense low level cold advection Wing to shift
se behind departing sfc cyclone this morning. Even so Delta t's
marginal within shallow moisture layer underneath strongly subsident
regime aloft and will refrain from entertaining any pops. That said
extensive closed cell stratocu expected to result and will side with
colder guidance temps.


Long term...(friday through wednesday)
issued at 257 am EDT Thu Oct 27 2016

High zonal flow continues southward of active nrn stream flow stuck
along and north of the US/Canadian border this period. Series of low
amplitude disturbances and accompanying sfc boundaries will
generally be devoid of significant low level moisture return not to
mention northward track of appreciable dynamical forcing. However
exception exists late Sat night into Sun morning tied to
frontogenetical response developing within coupled jet structure
aloft over the western lakes northward of stalling Ohio River frontal
zone. Deterministic run continuity not the best but consensus
signals good enough to follow blended pop bump. Other than brief
cooling sun remainder of the period to feature well above normal
temps...especially Sat and Tue.


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 632 am EDT Thu Oct 27 2016

Low pressure will continue to exit to the east this morning with
trailing sfc trough/cool front expected to track across remainder
of Northeast Indiana through 13z. Combination of this surface
trough, lingering forcing from departing mid level system, and mid
level dry slot will produce areas of drizzle along the low level
trough axis through about 13z at kfwa. Still cannot discount a few
more hours of IFR (ksbn), LIFR/ifr(kfwa) conditions until drier
air advects southward into the area later this morning. Flow off
Lake Michigan and strong low level inversion developing should
keep low clouds locked in through the day with bases gradually
rising above fuel alternate conditions later this morning or early
afternoon. Northwest winds in the 10 to 15 knot range are expected
today with winds diminishing to light and variable tonight as low
level ridge axis settles across the region.


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