Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 151958

Area Forecast Discussion
National Weather Service Northern Indiana
258 PM EST Thu Feb 15 2018

Issued at 258 PM EST Thu Feb 15 2018

Light rain and areas of fog will continue through the early evening
with dry and cooler conditions anticipated by late tonight.
Temperatures tomorrow will hover around freezing. There is a chance
of light rain or snow late Saturday with another...much
better...chance for widespread rain Monday into Tuesday. After a
seasonably cool weekend...temperatures warm back up for early next


.SHORT TERM...(This Evening through Friday)
Issued at 258 PM EST Thu Feb 15 2018

Intensifying upper level jet and associated low level fgen response
spreading light rain across the area. A few thunderstorms noted
upstream earlier but appears stable enough locally to preclude any
thunder in our area. Rain and snowmelt due to warm/moist air has led
to slow improvement in visibilities on southern fringes of advisory
as expected. Will drop a few counties but lack of rain and deeper
snowpack across our far NW could maintain dense fog through the
evening as suggested by latest HRRR and RAP. Have therefore extended
the advisory for those areas. Do expect improvement everywhere
overnight though as front passes and winds switch around to the
northwest. Rain will also end by late evening. A few lake effect
snow showers may be possible Fri morning but instability is very
marginal with 850mb temps only around -10C, low inversion heights,
and increasing dry air advection. Doubtful of anything measurable
but no qualms with inherited 20 PoP. Postfrontal CAA will lead to
lows dipping into the 20s with highs tomorrow only in the low/mid


.LONG TERM...(Friday Night through Thursday)
Issued at 258 PM EST Thu Feb 15 2018

After a seasonably cool and dry Sat morning, next shortwave arrives
late Sat. Midlevel CVA is decent but upper level jets are poorly
aligned with lackluster moisture return locally. Maintained just
chance PoPs with very light QPF. Expect a rain/snow mix with surface
wet bulb temps hovering in the low 30s. Little/no accumulation or
impacts expected.

Temps then rebound heading into early next week as next longwave
trough approaches. Deep SW flow develops and spreads ample
warm/moist air into the region. Highs could easily make a run at low
60s on Mon and Tue. Widespread rain also expected during this
time...though exact details on timing and amounts remain uncertain.
Will continue to watch this period for potential flooding concerns
given recent snowmelt/wet conditions. Cooler for the end of next
week but nothing unusual for this time of year with overall mild
pattern for the foreseeable future.


.AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 1157 AM EST Thu Feb 15 2018

Fog will continue of KSBN through the evening keeping LIFR flight
conditions over the terminal. IFR CIGS still over KFWA will
gradually lift as rain pushes in from the southwest. Both
terminals improve to MVFR by 06z with light winds out of the NW.
By morning winds pick up with gusts to 20 kts possible


IN...Dense Fog Advisory until 6 PM EST /5 PM CST/ this evening for

MI...Dense Fog Advisory until 6 PM EST this evening for MIZ077>081.




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