Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 200804

Area Forecast Discussion
National Weather Service Northern Indiana
404 AM EDT Wed Sep 20 2017

Issued at 400 AM EDT Wed Sep 20 2017

Visibilities could be near zero in some locations around daybreak
as fog continues to develop. The fog will dissipate by late
morning with mostly sunny skies in the afternoon. High
temperatures will rise well into the 80s. Very warm and dry
conditions will continue for the remainder of the week and into
the weekend with highs in the middle to upper 80s and even some
lower 90s possible.


.SHORT TERM...(Today and Tonight)
Issued at 401 AM EDT Wed Sep 20 2017

Surface temps to fall well below crossover and with recently wetted
ground anticipate fog to become more dense/prevalent through
sunrise. Dense Fog Advisory for all but far east/southeast CWA where
denser cloud coverage limiting outgoing longwave radiation.
Otherwise moderating low level thermal profile in advance of slowing
frontal boundary to afford strong diurnal rises with surface temps
on order of 10F higher than yesterday. Steepening surface lapse
rates also to afford mixout of fog no later than 14 UTC.


.LONG TERM...(Thursday through Tuesday)
Issued at 401 AM EDT Wed Sep 20 2017

Stoic ridging from eastern TX into the Upper Great Lakes between
active eastern Atlantic and digging western states trough.
Continued stagnation/thermal moderation to bring quite warm/humid
airmass through remainder of week as stalled frontal boundary w-n
decays. With time leeside Rockies trof to establish slow eastward
moving frontal boundary that may provide chance of convection by
about middle of next week.


.AVIATION...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 135 AM EDT Wed Sep 20 2017

LIFR conditions will likely remain in place through the remainder
of the night at KFWA as light winds and generally clear skies
allow for rapid fog/stratus formation this past evening. KSBN has
been slower to drop, bouncing around on the MVFR/VFR line past
couple of hours. HI res models suggest eventually they will drop
as well. Have backed off once again closer to 00z TAF at KSBN with
slower onset vs more  amendment that was done to get ahead of the
development. Trends will be monitored and TAFs amended if
downward spiral happens sooner (or not at all).

Any fog should burn off by 14Z with VFR conditions the remainder
of the period.


IN...Dense Fog Advisory until 10 AM EDT /9 AM CDT/ this morning for

MI...Dense Fog Advisory until 10 AM EDT this morning for MIZ077>081.

OH...Dense Fog Advisory until 10 AM EDT this morning for OHZ001-002-



LONG TERM...Murphy

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