Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 210924

Area Forecast Discussion
National Weather Service Northern Indiana
424 AM EST Tue Feb 21 2017

Issued at 323 AM EST Tue Feb 21 2017

A weakening cold front will move into our area today, likely
causing some showers, mainly northwest portions and mainly this
morning. Temperatures will remain unseasonably warm today. Light
winds and clearing skies should allow patchy fog to develop over
the area tonight. Dry conditions and very warm temperatures are
expected Wednesday as southwest winds strengthen ahead of an
approaching weak cold front. This front will drop into our area
Wednesday night and remain stationary Thursday. A strong low
pressure system moving northeast from the central Plains across
the Great Lakes will bring increasing chances of showers and
thunderstorms to our area Thursday night and Friday. Severe storms
with damaging winds are possible Friday as the cold front
associated with this system moves through the area. Temperatures
will remain unseasonably warm through Friday but return closer to
late February normals Saturday through Monday. The northwest flow
should result in some snow showers over the weekend, mainly
across northwest portions of our area.


.SHORT TERM...(Today and Tonight)
Issued at 323 AM EST Tue Feb 21 2017

Wkng shrtwv movg across the upr Grtlks today should result in band
of showers over IL/WI reaching our nw this morning, but wk
forcing/limited moisture suggests showers prbly won`t survive
into the se. CAA behind this system negligible with H85 temps
remaining near 10c today, but considerable cloudiness should
result in high temps a bit lower than yday. Tonight, drying in the
mid-upr levels combined with a wk low level gradient may result
in some fog/stratus development. Temps will remain very mild with
lows only in the 40s.


.LONG TERM...(Wednesday through Monday)
Issued at 323 AM EST Tue Feb 21 2017

Another shrtwv expected to move east across the upr Grtlks Wed.
Low level WAA and increasing swly gradient winds/mixing heights
should result in warmer temps with highs expected in the upr 60s
to lower 70s. Cdfnt associated with this shrtwv will move into our
area Wed night. Wk forcing and limited moisture should result in
little or no rain along the frontal boundary. This front will
stall over our area Wed ngt as flow aloft backs in response to
strong shrtwv digging into the central Rockies. As this system
moves into the central plains and strengthens Thu some showers may
develop along the strengthening stnry frontal boundary. Sfc low
still expected to lift ne Thu ngt transitioning stnry front to a
warm front which will lift north into MI. Showers and a psbly
tstms expected along this frontal boundary with greatest impact
across nrn portion of the cwa. As the strong low lifts ne across
the upr Grtlks Fri, a strong cdfnt will sweep east across our
area. Wk instability, but strong wind fields and deep layer shear
should result in a line of showers and psbly tstms along the
front, some of which could be accompanied by damaging winds. Temps
will again be very mild ahead of this front with highs expected
in the mid to upr 60s despite considerable cloudiness. Strong CAA
overspread our area Fri ngt will result in temps back to late Feb
normals on Sat. Wrap around moisture and upr trof movg through
will likely result in some snow showers Sat, especially across the
nw where some lake induced instability will be present as H85
temps fall below -10c. Generally dry wx with seasonable temps
expected Sun-Mon, though with contd nw flow still some potential
for snow showers, mainly nw into Sunday.


.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1245 AM EST Tue Feb 21 2017

Weakening cold front still expected to wash across the area later
today. Main change to TAF`s was to slightly improve expected
conditions. System lacks good upper support while low level
moisture and convergence are similarly lacking. Latest forecast
soundings indicate fuel alternate conditions may prove difficult
and KFWA could even remain VFR with frontal passage. This is
supported by upstream observations. Weak postfrontal CAA could
support some afternoon MVFR stratocu but even that is somewhat
questionable. Biggest aviation concern may be fog development at
the very end of this TAF period given light winds, nocturnal
cooling, and sufficient near-surface moisture.


LM...Small Craft Advisory until 4 AM EST early this morning for




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