Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 290140

Area Forecast Discussion
National Weather Service Northern Indiana
840 PM EST Mon Nov 28 2016

Issued at 357 PM EST Mon Nov 28 2016

Widespread rain will persist into the overnight hours. While
breezy conditions will prevail tonight, an isolated stronger
shower or thunderstorm on the back edge of the area of rain may
produce wind gusts to 50 mph. Rainfall amounts of one half to one
inch are expected, causing ponding of water as well as minor river
rises in some areas. High temperatures for the day will occur
into this evening as rising temperatures are expected. Steady
temperatures overnight will climb higher on Tuesday with highs
well into the 50s to near 60. More seasonable temperatures will
return for the second half of the week.


Issued at 821 PM EST Mon Nov 28 2016

Wind fields strengthening ahead of negatively tilted shrtwv
lifting ne across srn IL this eve with KIWX VWP indicating 45kt
in lowest gate. Sfc based inversion will limit downward transport
of these winds this evening but still expect some >40mph gusts.
Wk instability confined to trof axis. Latest HRRR/RAP suggests dry
slot will overspread our cwa ahead of the shrtwv, limiting
chances for tstms, but, will stick with slight chc through 06z,
and continue to monitor closely, as any deep convection will
enhance sfc gusts. Conditions this eve fcst well in going grids
and only minor adjustments made.


.SHORT TERM...(This Evening through Tuesday)
Issued at 357 PM EST Mon Nov 28 2016

Deep low pressure over SE North Dakota was making its impacts felt
as far east as the Great Lakes where surge of anomalously moist
air was heading north into the region. Expect widespread rain to
take over the forecast area into this evening with average
rainfall amounts of 0.75 to nearly 1 inch. While this will cause
some local ponding as well as minor river rises, somewhat larger
concern looms in the 23Z to 05Z window as dry slot rapidly works
northeast into the area. HRRR has been steadfast in developing a
narrow line of strong showers/isolated storms on the back edge of
the rain. 0-1 km shear values in excess of 50 kts and 0-1 km
helicity values in excess of 500 m2/s2 would suggest a non zero
risk for isolated tornadoes. However, low level
inversion/stability may hold just enough to keep the threat at
bay. Strong wind fields aloft may be mixed down to bring several
reports of 40 to 50 mph winds with the line. A lot of uncertainty
with regards to the evolution and amount of inhibition at the
surface warrants adding thunder mention and patching up HWO to
reflect brief wind threat. Trends will be monitored into the

Otherwise...occluded front will quickly push through and bring any
rain to an end by Tuesday morning. Rising temperatures this
evening will steady out overnight and then climb further on
Tuesday with highs into the middle 50s to around 60, depending on
amount of sunshine.


.LONG TERM...(Tuesday Night through Monday)
Issued at 357 PM EST Mon Nov 28 2016

Deep upper low will slowly drift east into Wednesday night,
forcing a cold front and a series of upper level disturbances
through the area. This  and bringing an end to the above normal
temperatures expected into Wednesday. Not much moisture to work
with so precip chances will be limited but still worth a mention.

Upper low will center SE of James Bay and continue to send several
additional waves through the region into the weekend with
difficult to time chances for rain and/or snow. No major systems
expected at this point so only slight chc to chc pops warranted,
mainly in the north.


.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 634 PM EST Mon Nov 28 2016

Strong storm across the region brings rain, winds and times of low
CIGs and VISBY. Expecting a period of IFR CIGs until around 07z,
when CIGs begin to trend higher. VISBY also looks to stay MVFR and
then increase around 05z as a dry slot begins to work into the
region. Am not totally confident that FWA goes has IFR CIGs for long
so only kept it in a temp group.  Wind shear is also expected in the
early portion of the period with a low level jet nearby.


LM...Gale Warning until 4 AM EST Tuesday for LMZ043-046.



LONG TERM...Fisher

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