Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 181808

Area Forecast Discussion
National Weather Service Northern Indiana
208 PM EDT Fri Aug 18 2017

Issued at 303 AM EDT Fri Aug 18 2017

A weak high pressure ridge will move across our area today
providing dry weather. A secondary cold front will move through
tonight and Saturday, likely causing showers and a few
thunderstorms. High pressure will move slowly east across the area
Saturday night through Monday, resulting in dry conditions with a
warming trend. Another cold front will move through the area
Tuesday, likely causing showers and scattered thunderstorms. This
will be followed by cooler and dry weather Wednesday and Thursday
as high pressure builds into the upper Great Lakes.


.SHORT TERM...(Today and Tonight)
Issued at 303 AM EDT Fri Aug 18 2017

Moisture wrapping around deep low over the upr grtlks will result in
strato cu across far nrn portions of the cwa this morning. This
will lift north during the day as the low pulls away and wk
ridging/subsidence builds in from the west providing mostly sunny
skies this aftn. Good mixing should allow temps to recover into
the upr 70s-lwr 80s.

Shrtwv over the nrn plains will move se to central IL tngt and then
east across IN/OH Sat. NAM/GFS in decent agreement suggesting
sufficient forcing/moisture and wk elevated instability for a band
of showers and isolated thunderstorms to move across much of the cwa
overnight, however, hires models more subdued suggesting iso-sct
coverage. For now continued with latest model blend pops, which
were generally a little higher than previous fcst, in the sct-
numerous range. Showers and renewed wk caa behind the secondary
cdfnt should allow temps to fall into the lwr 60s across the area
by Sat morning.


.LONG TERM...(Saturday through Thursday)
Issued at 303 AM EDT Fri Aug 18 2017

Sct showers/iso tstms may persist into Sat morning ern portions
of the area as the shrtwv moves through, with wk ridge in its wake
building into the area in the aftn providing dry conditions.
Broad ridging should persist across the area Sun-Mon resulting in
contd dry wx with a warming trend. Wk disturbance movg through
quasi-zonal flow north of the ridge will bring a chc of
showers/tstms to the area by Mon ngt, with a better chc Tue as a
stronger trof and associated cdfnt move nw-se across the cwa. Sfc
high moving slowly e-se across the grtlks in amplified flow aloft
should provide fair wx with blo normal temps Wed-Thu.


.AVIATION...(For the 18Z TAFS through 18Z Saturday Afternoon)
Issued at 208 PM EDT Fri Aug 18 2017

Brief mvfr cig restriction early this aftn but boundary layer will
continue to deepen/mix as upper trough over srn ON lifts out.
Otherwise attention turns toward incoming upstream sw trough
wrapping through ern MN. Fairly vigorous low level mass flux ahead
of this feature with substantial low level theta-e ridge inflection
seen into nrn IN after midnight with vcts mention added invof KSBN
and likely needed invof KFWA although cams based timing there more


IN...Beach Hazards Statement until 4 PM CDT this afternoon for INZ003.

MI...Beach Hazards Statement until 5 PM EDT this afternoon for MIZ077.

LM...Small Craft Advisory until 5 PM EDT this afternoon for LMZ043-




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