Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 170433

Area Forecast Discussion
National Weather Service Northern Indiana
1233 AM EDT Mon Jul 17 2017

Issued at 1205 AM EDT Mon Jul 17 2017

Skies will begin to clear later this morning as high pressure
builds into the region accompanied by seasonably cool weather to
start the week. Much warmer weather can be expected by Wednesday
as the low level flow becomes southwest. Highs today and Monday
will be mostly in the 70s, but then approach 90 by the middle of
the week.


Issued at 822 PM EDT Sun Jul 16 2017

Scattered thunderstorms focused earlier this evening along axis of
fairly strong low level convergence associated with southward
sagging frontal zone. Max instability axis of 1500-2000 J/kg ML
CAPE was also noted in vicinity of this stronger low level
convergence. A few reports of large hail received from these
storms despite rather marginal mid level lapse rates. Other
concern has been hydro with some training cells earlier this
evening across southern Putnam/northeast Allen county in northwest
Ohio. Bulk of severe threat has now shifted just southeast of
forecast area, although lingering heavy rain/small hail issues
likely to linger across Allen county Ohio through 930 PM. These
storms are likely largely diurnal driven and should begin to wane
in coverage and intensity after 930 PM.


.SHORT TERM...(Tonight and Monday)
Issued at 200 PM EDT Sun Jul 16 2017

Secondary weak sfc front making rapid progress across the CWA this
aftn and as thought in previous days failing to spark any
shower/storm development. 12Z surrounding raobs indicate why with
limited low level moisture return underneath fairly vigorous mid
level capping inversion. About the only chance will be through nw OH
and ern IL/wrn IN late this aftn timed with brief period of better
mid level forcing associated with sw disturbance over wrn lake SP
dropping due south and some weak low level theta-e
ridging...however even this looks to be isolated.

Otherwise broad sfc ridging will engulf the lakes on Monday.


.LONG TERM...(Tuesday through Saturday)
Issued at 200 PM EDT Sun Jul 16 2017

Turning decidedly warmer and more humid this period as significant
upper ridge builds out across the central plains. North through
northeast periphery of this feature will no doubt support an active
nw-se oriented frontal zone. Nonetheless highly doubt 90 degree
temps possible as seen in extended MOS guidance at times given
generally wet ground conditions within maximized cropscape. Mid 80s
more likely which will be uncomfortable enough as evapotranspiration
drives sfc dewpoints well into the 70s Thu on.

Timing of pertinent wx inducing sw disturbances of note in this
pattern sketchy at best and of which will dictate nwd reach of
active frontal zone. In addition likely upstream MCS generation and
downstream progression/evolution will modulate boundary placement as
augmented through convective outflow. Thus egregious blended pops
were largely abandoned in favor of a more targeted and conservative
approach with greater diurnal weighting in periods of better model
based consensus.


.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 1201 AM EDT Mon Jul 17 2017

The front along with the storms have moved well south of FWA. Kept
a mention of lower/MVFR CIGs at FWA as a TEMPO group as some of
these lower post frontal clouds may be able to develop/spread into
the area from the northeast. Otherwise, subsidence should
increase enough to help skies begin to clear by late morning and
through the afternoon. Otherwise, winds should stay light as a
weak pressure gradient remains over the area.


IN...Beach Hazards Statement until 4 AM CDT Monday for INZ003.

MI...Beach Hazards Statement until 5 AM EDT early this morning for

LM...Small Craft Advisory until 5 AM EDT early this morning for




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