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Area forecast discussion 
National Weather Service northern Indiana
817 PM EDT sun Sep 14 2014

issued at 806 PM EDT sun Sep 14 2014

Clouds will gradually increase overnight as a weak low pressure
system approaches the region. This system will also bring numerous
showers to the area beginning late Monday morning and continuing
through the evening. Lows tonight will generally be in the middle
40s. Highs tomorrow will be in the lower 60s near Lake Michigan
and middle to upper 60s along and southeast of Highway 24.


Short term...(this evening through monday)
issued at 254 PM EDT sun Sep 14 2014

As fast as low clouds began to mix out...diurnal cumulus erupted across
much of the area. However these have been steadily on the decrease
over the past couple of hours. Much of the night should end up
mostly clear into the evening before middle and high clouds begin to
move in from the northwest with the approach of the next wave. This
wave...currently dropping southeast through Saskatchewan will sharpen
somewhat as it reaches the western Great Lakes by 18z Monday. Bulk
of the forcing with this feature will impact the north and northwest parts
of the forecast area. Several of the high res models suggest a weak
impulse moving out of the plains just in advance of the main trough
that phases and potentially brings better chances for measurable
rain in southeast areas during the middle and late afternoon hours. Despite
much of the guidance leaning towards high likely and categorical
chances for rain have opted to keep things no higher than likely
with a good deal of dry air to overcome and not an overly dynamic or
moisture laden system.

Lows tonight will drop into the middle to upper 40s. Highs will be
tempered a bit by cloud cover and rain...especially northwest...reaching
the middle to upper 60s in most spots except far northwest where faster cloud
and rain arrival will limit heating.


Long term...(monday night through sunday)
issued at 254 PM EDT sun Sep 14 2014

Quiet stretch of weather expected Tuesday through Friday as surface high
pressure dominates in stable northwest flow...with temperatures remaining
below normal under a suppressed height field. This troughing relaxes
later Friday into next weekend which will support a modest warming
trend. Associated warm air advection surge within strengthening low level jet in advance of
an approaching upper trough/frontal boundary brings rain chances
back into question by next weekend...although confidence regarding
timing/depth of wave at this forecast range remains low.


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 802 PM EDT sun Sep 14 2014

Increasing middle/upper cloud cover overnight as northern plains
system approaches. Timed low end VFR ceilings in light rafl into both
ksbn/kfwa about 18/20 UTC respectively...followed by frontal passage/surface
wind shift and ceilings near/just above fueling/alternate requirements
towards end of forecast period. Should areal coverage/intensity of rafl
become greater...Post frontal ceilings could dip lower. Also...some
initial concern that br/fog issues could arise in subsequent
forecasts...closer to 09-12 UTC Tuesday.


Iwx watches/warnings/advisories...


short term...Fisher
long term...steinwedel

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