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fxus63 kiwx 211758 

Area forecast discussion
National Weather Service northern Indiana
1258 PM EST Thu Nov 21 2019

issued at 1256 PM EST Thu Nov 21 2019

Gusty southwest winds will continue through the remainder of the
afternoon along with pockets of light rain and drizzle. Winds will
shift to the west late this afternoon into this evening as a cold
front tracks across the region. Highs temperatures this afternoon
will top out in the low to mid 50s. Drier and cooler weather then
follows Friday with highs in the upper 30s to mid 40s.


Short term...(today and tonight)
issued at 212 am EST Thu Nov 21 2019

Impressive SW disturbance seen in vapor lifting northeast out of se
NE this morning and will generally shear out ahead of nrn stream
trough advancing ewd through srn Canada. Thus warm sector precip
shield is impressive at this hour much of this will slide well
northwest downstream of ejecting mid level circ track.

Weak Post frontal low level cold advection follows tonight with a
light shower or more likely drizzle holds on for a bit southeast
this evening. Otherwise incoming showers and copious cloud cover
will temper diurnal ranges and subdue more substantial potential
mixing as 850 mb winds within low level jet core peak near 60kts late
morning into early aftn.


Long term...(friday through wednesday)
issued at 212 am EST Thu Nov 21 2019

Brief sfc ridging advances through the Ohio Valley Fri ahead of parent
srn stream wave ejecting out of the Great Basin. Influence of nrn
stream feature topping West Coast upper ridge warrants continued
uncertainty in regard to potential influences on track of srn wave
through the Ohio Valley Saturday. GFS/ec/Gem now all in similar
agreement in taking a bit more left track which pokes into the srn
lakes. This in turn again poses some potential mixed phase p-types
underneath cold core/intense upper low late Sat morning through Sat
aftn given present timing. Strong dynamics within nrn arc of
deformation zone and certain diabatic adjustments within deep
vertical motion Field Point to decent snowfall potential especially
in light of nrn Kentucky to nrn Ohio deepening sfc low track.

Dry weather/brief zonal flow aloft follows sun-Mon before next
significant system emerges out of energetic wrn US landfalling
Pacific wave train. Thereafter late period and beyond looks quite


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1256 PM EST Thu Nov 21 2019

Pre-frontal trough type feature/warm advection induced rainfall
continues to spread across Northeast Indiana early this afternoon.
Strong gradient and eastward migration of strong sfc pressure
falls approaching the western Great Lakes has allowed for increase
in southwesterly winds over the past few hours. Southwest winds of
15 to 20 knots with gusts to 30 to 35 knots will be possible
through the afternoon hours as sfc low pressure slowly deepens
across east central Wisconsin. Bulk of warm advection/pre-frontal
precip should gradually shift eastward over next few hours. Some
additional light rain or drizzle will be possible with cold
frontal passage later this afternoon into this evening. Cigs
should continue to deteriorate to lower end MVFR and possibly IFR
levels this afternoon, with gradual improvement late tonight in
Post-frontal cold advection. Cigs should tend to scatter during
the morning Friday as much drier low level air advects across
northern Indiana.


Iwx watches/warnings/advisories...
Lm...Small Craft Advisory from 7 PM this evening to 4 PM EST Friday
for lmz043-046.

Gale Warning until 7 PM EST this evening for lmz043-046.



short term...T
long term...T

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