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Area forecast discussion 
National Weather Service northern Indiana
100 PM EDT Tuesday Jun 30 2015

issued at 353 am EDT Tuesday Jun 30 2015

A cold front will sweep through the area today...bringing a chance
of showers and thunderstorms to the region. Severe weather is not
expected...but locally heavy rainfall is possible. Skies will
clear out tonight. Highs will reach the lower to middle 70s with
lows tonight dropping to the upper 50s to lower 60s.


Short term...(today and tonight)
issued at 353 am EDT Tuesday Jun 30 2015

Handful of issues to deal with for this package.

Low clouds have overtaken much of the forecast area courtesy
moist boundary layer conditions from recent rainfall as well as
increasing humidity ahead of an approaching wave and cold front.
Pockets of dense fog have been noted on observations but so far
seem to be patchy enough to hold off on any headlines. Special Weather Statement issued
to handle for now.

To the west...widely scattered showers and thunderstorms continue
to scoot slowly east into far western parts of the area. This are
associated with an approaching upper level wave that is expected
to deepen somewhat today with a cold front sweeping in this
afternoon. High res models generally take this shower activity
slowly east and dissipate to some extent. However...after 15z
instability begins to ramp up and front draws closer setting the
stage for at least scattered shower and thunderstorm development.
Have kept probability of precipitation in middle to high chance and focused best shot in the
east where timing of front and diurnal uptick should allow for
better coverage. Some concern that stratus will hamper
development...but soundings show inversion mixing out despite
limited sunshine. Severe weather not expected but can't rule out a
stray small hail or local stronger wind gust as well as locally
heavy rainfall. Coverage and duration of any precipitation should limit
any additional Hydro concerns.

Conditions should improve this evening as front clears the area
and drier air filters in. Lows will drop into the upper 50s to
around 60s.


Long term...(wednesday through monday)
issued at 353 am EDT Tuesday Jun 30 2015

Series of shrtwv's over southwestern Canada/NE Pacific expected to top western ridge
and drop southeastward into the middle MS/lower Ohio Valley mid-week. This track
should result in surface frontal boundary which will move through the
County Warning Area during the short term period... remaining far enough south of
our County Warning Area for dry weather here Wednesday-Thursday as high pressure moving slowly east
across the Great Lakes dominates. Latest medium range models suggest this
dry spell could last through Saturday before stationary front lifts back
north-NE as a warm front in response to deep upper low currently over Gulf
of Alaska moving east into central Canada on Sunday. For now
maintained low chance probability of precipitation over the Holiday weekend with better chance
Monday as the cold front associated with this system moves into the
Midwest. With front remaining south of the area and NE flow
dominating... expect temperatures will remain below normal through the
week... with warm air advection resulting in a warming trend to seasonably warm
temperatures by Sunday/Monday.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 100 PM EDT Tuesday Jun 30 2015

Short wave upper trough and associated surface wave currently moving
across the area. Kiwx radar indicated precipitation with this system has
moved east of both taf sites while visible Sat shows area of clearing
skies moving in from the west. Will continue to monitor up until
issuance time but thinking now is that ksbn will scatter out by 18z
and kfwa not long after. That leaves main issue this cycle of
overnight fog/low cloud development. Both sites went down to LIFR
last night and with addl rainfall this morning...middle level drying
working in tonight...and light winds expect a repeat again
overnight...keeping just above Airport minimums at this time.


Iwx watches/warnings/advisories...


short term...Fisher
long term...jt

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