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Area forecast discussion 
National Weather Service northern Indiana
806 PM EDT Friday Jul 29 2016

Synopsis...
issued at 749 PM EDT Fri Jul 29 2016

Scattered showers and thunderstorms will gradually diminish in
coverage later this evening. A couple of upper level disturbances
will track across the region through the first part of the weekend,
bringing more scattered showers and thunderstorms to the region
for Saturday afternoon and evening. Mainly dry conditions are
expected on Sunday. Low temperatures tonight will drop into the
mid 60s. High temperatures on Saturday will be around 80 degrees.

&&

Update...
issued at 749 PM EDT Fri Jul 29 2016

Broad perturbed mid/upper flow combined with diurnal instability
has once again allowed for scattered-numerous showers and storms
across the area this afternoon/early evening. Earlier this
afternoon main focus was along lake enhanced convergence zone
across the far northwest, with recent trends taking primary focus
into portions of far Northeast Indiana/Northwest Ohio where low
level moisture convergence appears to be maximized early this
evening. Have continued trend of previous forecast with gradual
pop rampdown late evening/overnight, although broad upper level
short wave working in from the mid MS valley and persistent weak
elevated instability will keep slight chance-low chance pops going
overnight. A few locations experienced some flooding issues this
afternoon, with still a low end possibility of some localized
pockets of heavier rain across the eastern third of the area
through late evening.

&&

Short term...(this evening through saturday)
issued at 212 PM EDT Fri Jul 29 2016

Chaotic pattn sfc and aloft this aftn. Old synoptic fntl zone had
mixed into swrn zones W/composite outflw/wk cdfntl zone through
srn Michigan. Meanwhile aloft...W-E vort channel and wk mid lvl
frontogenesis overhead conts to persist ewd of fractured SW
disturbances extending FM se NE into wrn Illinois. Given stg
heating/destabilization ongoing xpc dvlpg convn ovr W/SW areas in
proximity to old synoptic bndry will expand ewd inadv of apchg
wave coming out of wrn Illinois and build ewd acrs nrn in lt this aftn
and into Ohio by evening.

Otrws activity contg within composite bndry ovr srn Michigan into NW Ohio
likely to persist until lead SW disturbance pivots through this
evening. In all most areas esp nwd of the Highway 24 corridor shld
see a more generous coverage of shra/tsra this aftn evening as
this sys works through the area. Contd wk flw aloft within an
appreciably moist airmass again points to localized heavy rainfall
yet without a more coherent focus aloft nor sig ll mass flux no
water related headlines needed.

Ltl chg xpcd on Sat as pattn aloft persists W/primary mid lvl trough
axis finally making a push east lt Sat night. Will expand prior pops
while emphasizing nrn half for btr implied chc both Sat aftn and eve
tied to diurnal heating cycle and persisting mid lvl convergence.

&&

Long term...(saturday night through friday)
issued at 212 PM EDT Fri Jul 29 2016

Ridging aloft to build sigly and spread ewd into the wrn lakes
this pd as east Canada troughing breaks down although that appears
likely to redvlp twd dy8. Regardless lg scale pattn suggestive of
conv complexes dvlpg within nrn periphery of growing
heat/instability dome acrs the plains as Erly as lt Tue yet deemed
moreso twd Wed and then persisting through Fri pending degree of
ridging that blds newd into the grtlks. Regardless at this range
will truncate fallacious blended pops to lwr bound chcs given lack
of model based temporal consensus on both upr ridge placement and
intensity.

&&

Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 749 PM EDT Fri Jul 29 2016

Showers/storms will affect kfwa over the next hour or two, with
focus expected to shift east of kfwa after 02z or 03z. Brief MVFR
vsby/cigs are possible with the heavier showers/storms at kfwa
over the next few hours. Precip to become more isolated/widely
scattered in nature late this evening and will keep tafs mainly
dry after 04z with low confidence in occurrence for point
forecasts. Weak flow/moist boundary layer may once again rise to
some patchy fog overnight, and have continued with idea of
previous forecast in IFR/MVFR conditions developing for the 09z-
13z timeframe. Mid/upper level trough axis to slowly track across
the region Saturday with another day of scattered showers/storms
expected. Have confined vcsh mention to ksbn at this forecast
distance with expected lake breeze convergence contribution once
again. Winds to remain light through the period outside of any
heavier showers/storms.

&&

Iwx watches/warnings/advisories...
in...none.
Michigan...none.
Ohio...none.
Lm...none.
&&

$$

Update...marsili
synopsis...marsili
short term...T
long term...T
aviation...marsili



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