233
fxus63 kiwx 262323
afdiwx
area forecast discussion
national weather service northern indiana
623 pm est mon jan 26 2026
.key messages...
- some patchy blowing and drifting snow continues through early
evening, but blowing and drifting snow is expected to become
more widespread late tonight into tuesday. peak wind gusts to
30 to 35 mph late tonight and monday will result in blowing
and drifting snow and pockets of significantly reduced
visibilities. some light snow accumulations of an inch or two
possible north of the toll road late tonight into tuesday.
- wind chills as low as 15 below to 25 below tonight. periodic
wind chills of around 15 to 20 below are also possible at
times through the remainder of the work week.
- additional lake effect snow chances wednesday through friday,
with higher chances on friday.
&&
.discussion...
issued at 237 pm est mon jan 26 2026
passage of a mid level wave is ushering in much drier low level air
to the great lakes/ohio valley this afternoon via backing low level
winds associated with an incoming low level ridge axis. the next
upstream upper trough is already inducing some weak cyclogenesis
across southwest ontario, and this wave and associated cold
front will be primary forcing mechanisms for additional snow
showers late tonight into tuesday. this event will feature much
less organization in terms of lake response given more shallow
lake induced instability depths and a more west-northwest fetch
in comparison to this morning. progressive synoptic forcing and
somewhat limited moisture profiles/limited fetch should limit
additional lake effect/enhancement accums to the 1 to 3 inch
range late tonight into tuesday evening, with greatest impacts
from falling snow in the 10- 16z period.
broad sfc pressure falls associated with low level waa will shift
across the great lakes overnight and eventually to the eastern great
lakes daybreak tuesday. tightening low level height gradient and
migration of these pressure falls should result in an abrupt
increase in southwest wind gusts overnight with a potential of some
30+ mph gusts in the 08-14z timeframe coinciding with rise/fall
couplet in isallobaric gradient and approach of low level cold
front. given the very dry/flurry nature and 20-30:1 snow to
liquid ratio of recent snow, in particular lake effect snow,
there is a concern for some blowing and drifting snow with
impacts likely across especially rural/open areas. upon
expiration of the winter weather advisories/warnings this
morning, did go ahead and include a winter weather advisory for
laporte/st. joseph/elkhart in in, along with berrien/cass/st.
joseph in counties for late tonight through tuesday evening.
this was done where additional light accumulations are maximized
and where confidence in impacts are the greatest. did issue an
sps for the remainder of the area highlighting this potential.
in terms of temperatures/wind chills, some good temp drops are
possible early evening as winds slacken for a brief time and where
mostly clear skies persist. temperatures should level out this
evening and then rise overnight as waa strengthens, but wind
chills will still be bitterly cold as increases in wind speeds
offset these leveling temp trends. no changes anticipated at
this time to the cold weather advisory.
the continuous stream of upper troughs dropping through
downstream portion of the eastern pacific ridge will continue
later wednesday with another push of low level cold advection
and more lake effect snow showers. lake parameters look even
more marginal with this wave with a bit more suppressed
inversion heights and depth of instability. perhaps best chance
of additional lake effect snow showers will be sometime late
work week with several disturbances rotating through broad
eastern conus negative upper height anomaly help to create more
favorable northerly trajectories.
additional periods of potential cold weather advisory conditions
will likely arise through remainder of the work week. present
indications in medium range guidance still point toward better
chance of at least some moderation in temps this weekend into early
next week.
&&
.aviation /00z tafs through 00z wednesday/...
issued at 622 pm est mon jan 26 2026
mid level ridging quickly gives way to another upper low and
associated vorticity by early tuesday morning allowing a return to
lake effect snow late tonight/early tuesday morning. for sbn, a
boundary moving through in the 7 to 9z window may cause an initial
burst of snow before lake effect snow gets going midday into the
afternoon. at this point, am most confidence in mvfr cigs, but there
is some lowered confidence due to trajectories about if the snow can
stay just to the north of sbn. fwa may get in on that initial burst
of snow from the boundary moving through, but it may also stay just
south of the lake effect snow. will also include mvfr cigs, but keep
lowered visby due to snow out of fwa`s tafs as well. the recent snow
and gusty winds do not take into account any blowing snow impacts to
terminals.
expect southwest winds to veer towards westerly mid to late morning.
gusts also pick up pretty quickly in the taf period, acquiring 23 to
28 kt gusts, slowly waning by the evening hours. will also have a
brief period of llws at the terminals as a warm front washes out
overhead, but with lapse rates building quickly tuesday am, will
also end it early.
&&
.iwx watches/warnings/advisories...
in...cold weather advisory until 10 am est /9 am cst/ tuesday for
inz005>009-012>015-017-018-020-022>027-032>034-103-104-
116-203-204-216.
winter weather advisory from 1 am est /midnight cst/ to 7 pm
est /6 pm cst/ tuesday for inz005-103-104-203-204.
oh...cold weather advisory until 10 am est tuesday for ohz001-002-
004-005-015-016-024-025.
mi...cold weather advisory until 10 am est tuesday for miz078>081-
177-277.
winter weather advisory from 1 am to 7 pm est tuesday for
miz078-079-177-277.
marine...none.
&&
$$
discussion...marsili
aviation...roller