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Area forecast discussion 
National Weather Service northern Indiana
843 PM EDT sun Jul 27 2014

issued at 305 PM EDT sun Jul 27 2014

Isolated thunderstorms will come to an end this evening across
Northwest Ohio as an upper level disturbance exits the region. Much
cooler and drier air will filter into the region tonight behind
this system...with dry conditions and cooler than normal
temperatures expected for much of next week.


issued at 830 PM EDT sun Jul 27 2014

Scattered showers and thunderstorms continue early this
evening...mainly east of Interstate 69 and focused along distinct
low level boundary. This convergence boundary appears to be linked
to secondary surface trough...which has also been sharpened by
marine influence and several residual outflow boundaries. Axis of
greatest instability has shifted east of the area...and while
maintenance of these showers and thunderstorms will likely
continue over next hour or two across Northwest Ohio...storms are
expected to be subsevere with wind gusts to around 40 miles per hour possible
along with some small hail. Some small tweaks made to probability of precipitation to
account for ongoing convection...but otherwise no significant
changes made to the forecast at this time.


Short term...(this afternoon through monday)
issued at 305 PM EDT sun Jul 27 2014

Broken convective line segments/supercells potentially containing
large hail and damaging winds remains the primary concern this
afternoon as cold front on leading edge of cold pocket aloft edges
east over a very moist/unstable boundary layer. Severe watch 446 has
been issued for the entire forecast area with convective line already into Northwest
Indiana/SW lower Michigan as of 1830z given MLCAPE erosion with temperatures
reaching the low/middle 80s across northern/western zones. Resulting
SBCAPE Reservoir near 3000 j/kg amid 40-50 knots of deep layer
shear favors organization and this hail/wind threat. The tornado
risk remains low given meager 0-1 km helicity/shear values.
Otherwise...expect a few showers/embedded thunder to linger
across mainly northern portions of the forecast area into this evening under
a compact closed low forecast to drop southeast through the lower
lakes from central WI.

Cold air advection regime in deepening north-northwest flow in wake of this vigorous
shortwave/cold front should ensure dry/much cooler weather later tonight
into Monday.


Long term...(monday night through sunday)
issued at 305 PM EDT sun Jul 27 2014

Steady state amplified follow regime expected to continue through this
period...anchored out west by upper ridge extndg northward through southwestern Canada
and east by deep upper low centered near James Bay. As a result expect continued
dry nwrly ll follow and pleasant temperatures through the period.

Some convoluted suggestion in some medium range guidance of tertiary
disturbances wrapping through the base of middle level through centered
through the eastern lakes...particularly the op GFS depiction on Tuesday/
Wednesday. However it stands alone in dropping a SW disturbance well southward of
any other guidance. As such will hold west/dry weather throughout.


Aviation...(for the 00z tafs through 00z Monday evening)
issued at 830 PM EDT sun Jul 27 2014

Secondary surface trough has cleared terminals at 00z...and potential
for additional precipitation appears to have ended for the
evening. An area of moderate strong pressure rises of 3-4 mb/3 hour
is working into North Central Indiana and will provide brief
enhancement to stronger northwest winds through 01z or 02z. Cold
air advection overnight and moisture wrapping around parent system
will yield potential of some MVFR ceilings late tonight into Monday
morning. Diurnal mixing will allow for northwest gusts to around
20 knots on Monday with VFR conditions expected by midday.


Iwx watches/warnings/advisories...
in...beach hazards statement through late Monday night for inz003.

Michigan...Beach hazards statement through late Monday night for miz077.

Lm...Small Craft Advisory until 5 am EDT Tuesday for lmz043-046.



short term...steinwedel
long term...T

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