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Area forecast discussion 
National Weather Service northern Indiana
338 am EDT Thursday Jul 28 2016

issued at 328 am EDT Thu Jul 28 2016

Shower and thunderstorm chances will increase this afternoon and
persist into Saturday as a weak frontal boundary and series of
disturbances move through the region. Severe weather is not
expected...but locally heavy rain is possible with any
thunderstorms. Highs will reach into the lower to middle 80s with
overnight lows in the middle 60s.


Short term...(today and tonight)
issued at 328 am EDT Thu Jul 28 2016

Through 8 am...thunderstorm has recently developed south of
Milwaukee drifting slowly east. Isolated showers/storms had also
formed earlier over southern lk Michigan in what appears to be an area of
weak convergence. Widely scattered light showers also have been
attempting to move slowly NE out of central Indiana into far southeast
areas on nose of increased Theta-E. These have been weakening as
they move closer and away from better moisture. Can't rule out a
touch of rain occurring but not worthy mention in zones at this

After 8 am...slowly increasing surface dewpoints will continue to
advect in today with mid to possibly upper 60 dewpoints possible.
This combined with temperatures in the 80s will allow for a weakly
unstable uncapped atmosphere will be in place as a disturbance drops
out of southeast Minnesota into the Great Lakes during peak heating. The
wave will push a weak surface boundary south providing a limited
focus for widely scattered to scattered showers and storms. This
front was responsible for a line of storms across central lower
Michigan yesterday with a outflow from it meeting its demise
somewhere over the forecast area this past evening. Given these
details...think the 30 to 40 percent pops are warranted across the
northern portions of the area into the afternoon with the chances
likely focusing more across central and southern areas during the
evening (maybe overnight) hours tonight as the front continues
south. No concerns for severe weather as little in the way of shear
exists with 0-6 km bulk shear barely reaching 15 kts but this same
weak flow will set the stage for slow moving storms that may drop a
good deal of rain in some spots.


Long term...(friday through wednesday)
issued at 328 am EDT Thu Jul 28 2016

Challenges will reside with impacts of increasing upper level
ridging through the first half of the period (into monday) followed
by flattening of the ridge as a series of stronger waves move out of
the plains.

Frontal boundary will reside not to far from the area with lingering
chc pops in SW sections Friday and eventually across all areas into
Saturday. Dry period looks to be on tap Sat ngt into Monday night as
ridging pushes axis of precip north and slowly increase heat and
humidity towards mid week. As noted above...ridge may break down
some and allow "ring of fire" to come back into the area towards the
end of the period. Superblend leans towards mid to even high chc
pops in this period but given concerns on location of ridge and
timing of waves...collaboration resulted in lowering to slgt chc
pops for most offices.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 149 am EDT Thu Jul 28 2016

Overall anticipate VFR met conditions through the forecast period.
Concern for late afternoon convection amid several upstream
shortwaves and near/just after optimal surface
heating/destabilization. Still chances appear too low for anything
more than a thunderstorms in the vicinity/cumulonimbus mention. Later forecasts to likely provide
more explicit timing for possible tempo mention.


Iwx watches/warnings/advisories...


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

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