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fxus63 kiwx 221051 

Area forecast discussion
National Weather Service northern Indiana
651 am EDT Sat Jul 22 2017

issued at 530 am EDT Sat Jul 22 2017

Showers and thunderstorms will gradually diminish this morning.
Localized flooding is possible in areas that received over an inch
of rain last night. There will be a lingering chance for
thunderstorms this afternoon and evening...especially south of the
Highway 24 corridor. Another system will move through the region
Sunday afternoon and evening with chances for thunderstorms again
during this period. Drier and cooler air will then prevail for the
first part of the upcoming week.


Short term...(today and tonight)
issued at 530 am EDT Sat Jul 22 2017

Several mesoscale convective complexes moving through the region
this morning. First mesoscale convective vortex rotating through eastern area and severe
threat this morning ending as this feature exits. Strong warm air
advection and low level jet to our west has fueled a second mesoscale convective system over
eastern Iowa and northern Illinois and this making its way into Northwest Indiana
early this morning. Primary concern will be heavy rain threat rest
of this morning with pwats still over 2 inches. Expect this complex
to begin weakening as it translates through the area this morning as
low level jet weakens and moisture convergence diminishes.

Focus then shifts to afternoon convection and severe chances. Fully
expect composite outflow from this morning convection to be well
south of the area today and stable bubble over most of County Warning Area. Clouds
will linger this morning and possibly into this afternoon once again
limiting heating and keeping thermal gradient to our south. High dew
point air still in place and even with clouds could see cape of at
least 1500-2000 j/kg develop. However lack of focus and with
boundary south of area along with local cin thinking best chances
for any development will be in our far south. Last several cams runs
tend to agree and latest hrrr develops storms along our southern
border. Will trend afternoon pops in this direction with highest in
our far south. Isolated severe will be possible where storms do
develop and again primarily focused in our far southern counties.
Evening storms should then push south of the area with approach of
first synoptic frontal boundary and drying overnight.


Long term...(sunday through friday)
issued at 530 am EDT Sat Jul 22 2017

Short wave and associated secondary cold front to swing south Sunday
into Sunday evening. Models continue to indicate possible convection
with these features as low level moisture lingers and cape values
increase to over 2000 j/kg. Deep layer shear also increases to over
30 knots so isolated severe not out of question and thus the day 2
slight risk. Once this wave passes should finally see drier and
cooler air work in for Monday and first half of upcoming week.

Another short wave in west northwest flow looks to arrive mid week
with another sagging surface front. This will bring chances for
showers and storms back to the area for latter half of the week.
Basically accepted blends for later periods with focus this morning
on short term weather.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 645 am EDT Sat Jul 22 2017

Morning radar showing break between convective complexes but some
scattered showers and occasional lightning developing in the area
between. Will see pcpn diminish by late morning as next complex
moves in then weakens and dissipates. Stable bubble over the area
through much of the afternoon and with no strong focus for
additional convection will likely be dry at terminals. Boundary
south of kfwa will see some development this evening and it could
be close enough for a stray shower or storm at terminal.
However...chances remain too low for inclusion in forecast at this


Iwx watches/warnings/advisories...


short term...Lashley
long term...Lashley

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