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Area forecast discussion 
National Weather Service northern Indiana
103 am EDT Thursday may 28 2015

issued at 752 PM EDT Wednesday may 27 2015

Light winds and clearing skies are expected tonight into Thursday
as high pressure builds into the region. Some patchy fog may
develop towards daybreak. Lows tonight will range between the
middle to upper 50s. With ample sunshine...highs will recover
into the lower 80s on Thursday. Thunderstorm chances return later
Friday into Saturday as a strong cold front moves through the


Short term...(this evening through thursday)
issued at 411 PM EDT Wednesday may 27 2015

Threat for showers/thunder and severe weather will quickly end across the
area by early this evening as large scale low-middle level shortwave
trough and embedded vorticity maximum now working through the lower lakes
shifts east in progressive flow. Building middle level heights and
deep layer subsidence in wake of this feature will allow low
level ridging to work in overnight into Thursday. Resulting
clearing skies, light winds, and residual soil/surface moisture from
today's rainfall may be enough to promote patchy ground fog
formation toward daybreak. Dry with ample sunshine otherwise
tomorrow with highs recovering into the low 80s.


Long term...(thursday night through wednesday)
issued at 411 PM EDT Wednesday may 27 2015

Strong low level thetae advection to commence Thursday night as
low level anticyclone shifts off to the east. Forcing will be
relatively meager through at least early Friday afternoon as
attention shifts upstream across the central and northern plains
and a consolidating upper trough. Best chance of showers and
thunderstorms appears to be in the Friday night through early
Saturday timeframe. On Friday night...expecting remnants from
upstream convection to spill into area as low level jet veers and
becomes more southwesterly. Shear profiles should be relatively
marginal however...with more significant deep layer shear not
affecting the area until Saturday in closer proximity to the
associated cold front.

The strong cold front with this system will approach for
Saturday...although instability magnitude should be somewhat
limited. Guidance still differs quite a bit regarding progression
of this front...with NAM remaining a slow outlier. Low confidence
in severe potential at this point given marginal middle level lapse
rates...frontal timing uncertainty...and perhaps overall limited
instability. Trend to much cooler temperatures for for Saturday
night/Sunday behind the front...although temperatures should recover
relatively quickly for the Tuesday-Wednesday period.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1256 am EDT Thursday may 28 2015

VFR conditions expected most of this period. Weak cold front has moved
through northern Indiana and weak high pressure quickly building into the
area. Light winds and mostly clear skies overnight may allow some
br to form. Continued to just mention this in FWA taf as dewpoints running
a little higher there and more significant rainfall occurred yesterday across
NE Indiana. Br should burn off quickly this morning followed by
just a few cumulus as warm air aloft associated with an upper level ridge
moves across the area.


Iwx watches/warnings/advisories...


short term...steinwedel
long term...marsili

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