462
fxus63 kiwx 200521
afdiwx
area forecast discussion
national weather service northern indiana
1221 am est tue jan 20 2026
.key messages...
- lake effect snow showers continue this evening generally north
of the toll road. additional snow accumulations will be just
an inch or two, but strong winds this afternoon to 35 mph will
result in some blowing/drifting snow and pockets of
significantly reduced visibilities.
- cold weather advisories continue tonight for much of the area with
wind chills of 10 below to 20 below.
- another system will bring light snow accumulations late tuesday
night into wednesday morning. the greatest potential of
accumulations over an inch is north of us route 6.
- temperatures warm briefly into low to mid 30s for wednesday
but an arctic airmass and much below normal temperatures
return for later work week into the weekend.
- there are additional periodic chances of lake effect snow
showers through the weekend.
&&
.discussion...
issued at 335 pm est mon jan 19 2026
multiband lake effect snow showers continue this afternoon with
interstate 80 corridor marking the southward extent of these snow
showers. accumulation efficiency and snow ratios may become less
ideal as thermal profiles in layer with strongest lift are in
fringes of dendritic growth zone layer. inversion heights remain
fairly impressive from 6-7k feet, but moisture profiles dry out
rapidly above this inversion. could see another inch, possibly
locally 2 inches of lake effect snow showers tonight across southern
lower mi. snow amounts do not tell the whole story in terms of
impacts with this setup, as the combination of strong wind gusts to
35 mph and the dry nature of snow should allow for continued
blowing/drifting snow through this evening and areas of
significant visibility reduction. this threat may taper late
afternoon across in portion of the winter weather advisory, but
would suspect visibility concerns could persist through much of
the early evening across southern lower michigan. another
synoptic upper level trough could provide some brief enhancement
to the snow showers late evening/early overnight. this trough
will spread a mid cloud deck across the area late
evening/overnight with a potential of a few flurries outside of
the lingering lake effect snow showers.
in terms of the wind chill headlines, the cold weather advisories
will be left intact with this issuance. maintenance of some gradient
overnight should allow only modest drops in the single digit above
zero temperatures tonight. the slowly diminishing wind speeds this
evening will likely be offset by the small decreases in sfc temps to
provide stable wind chills in the -10 to -20 degree f across the
advisory area. areas outside of the cold weather advisory across
southwest lower michigan may flirt with advisory criteria late this
afternoon, but confidence remains too low to expand the cold weather
advisory into these areas. areas across the southwest could have
temps not reach advisory criteria for a good part of the night
if some better decoupling can occur closer to the low level
ridge axis.
tuesday will feature the beginning of a warm advection pattern that
should support highs from mid teens northeast to around 20
southwest. a 120 knot upper speed max is forecast to dive
southeast down the eastern pacific upper ridge to carve out next
short wave trough of interest reaching the western great lakes
late wed afternoon. this should allow for snow to develop
downstream of this feature tuesday night into early wednesday.
greatest chance of snow with this forcing appears to be along
and north of us 6, but there will likely be a sharp south to
north cut off in this waa setup that will need further
refinement. early indications would suggest at least a potential
of some 1 to 3 inch accumulations north of us route 6 during
this period. precip could end with some drizzle ptypes later
wednesday as moisture depths quickly drop off in the pm.
one item that may need to be watched for wednesday is potential of
some strong southwest wind gusts for a time in the morning east of i-
69. the low level jet preceding the wednesday system should be
shifting east wednesday morning, and a short window may exist of
better diurnal mixing before low level winds drop out significantly.
this could support brief period of some 35+ mph gusts nw ohio
wednesday morning/early afternoon.
after a day of milder conditions wednesday, the remainder of the
forecast looks to turn back to much below normal temperature-
wise once again. a 490 dm upper low will drop across southern
ontario thursday with bitter cold airmass sinking southeast
across great lakes/ohio valley region thursday night through
saturday. some renewed lake effect snow chances are in store
especially late thursday into saturday as this colder air
filters in, with similar looking lake effect parameter profiles
as that of today. a few nights of wind chills approaching
criteria are possible fri night/sat night.
the duration of this arctic airmass remains an item of lower
confidence and will depend on timing of additional nw flow waves
late weekend into early next week. however, based on longwave
pattern of western conus ridging, below normal temps are likely
to continue into early next week.
&&
.aviation /06z tafs through 06z wednesday/...
issued at 1220 am est tue jan 20 2026
lake effect snow/stratus will continue at ksbn through the
early morning but conditions will steadily improve as inversion
heights lower, winds back slightly, and dry air advection
increases. confidence in the exact timing of the transition to
vfr is low but should occur no later than 13z. vfr then expected
for the rest of the period given shortwave ridging. the next
trough moves into the great lakes early wed morning and may
bring some more light snow/mvfr ceilings to ksbn but that
appears to be just outside this forecast window.
&&
.iwx watches/warnings/advisories...
in...cold weather advisory until 9 am est /8 am cst/ this morning
for inz005>009-012>015-017-018-020-022>027-032>034-103-
104-116-203-204-216.
oh...cold weather advisory until 9 am est this morning for ohz001-
002-004-005-015-016-024-025.
mi...cold weather advisory until 9 am est this morning for miz080-
081.
winter weather advisory until 1 am est early this morning for
miz078>081-177-277.
marine...heavy freezing spray warning until 7 am est this morning for
lmz043-046.
small craft advisory until 4 pm est this afternoon for lmz043-
046.
&&
$$
discussion...marsili
aviation...agd