244
fxus63 kiwx 170920
afdiwx
area forecast discussion
national weather service northern indiana
520 am edt sat oct 17 2026
.key messages...
- widespread frost is expected saturday night into sunday
morning with a potential of temperatures dropping to the
freezing mark, especially east of in-15. a frost advisory and
freeze warning have both been hoisted.
- after the below normal temperatures this weekend, temperatures
rebound back above normal for much of next work week with dry
weather expected.
&&
.discussion...
issued at 304 am edt sat oct 17 2026
surface high pressure continues to build in causing low level
moisture to dissipate, lake induced instability to wane, and low
level trajectories to become more southerly. as lake enhanced rain
dissipates early this morning, dry air takes over and we`re in this
dry pattern for the foreseeable future. this is as the upper jet
retreats into mi and upper ridging builds into areas east of the
rockies. an area of low pressure washes out between wednesday and
thursday as a cold front pushes southeastward ahead of another
surface high. the ecmwf has rain approaching the area, but that`s
really the only model that does so.
otherwise, the temperatures are the most noteworthy piece of
weather that should be discussed here. morning temps fell back
into the 30s this morning, but lingering wind and limited
decoupling restricted frost formation to patchy at best despite
temperatures falling into the mid 30s and even some low 30s in
some outlying spots. 850 mb temps this morning reached around
-2c and, even as that aforementioned return flow takes over, we
have our lowest temperatures of this young cool season as
freezing temperatures look to settle in along and south of
us-24. the give and take between surface high pressure-affected
weak flow and encroaching strengthening gradient to our north
and west once again lessens confidence on frost formation on the
northern side of our freeze watch for sunday am. there are
signs in forecast soundings of a decoupling boundary layer sun
am and again mon am, although lesser confidence in frost occurs
monday and even lesser for tuesday. while waa doesn`t appear to
be established in the following days, temperatures are forecast
to trend warmer, rising above 40 degrees by wednesday am. highs
surpass 70 degrees again tuesday morning, although a few areas
in white, pulaski, cass, and fulton could achieve 70f monday as
well.
&&
.aviation /12z tafs through 12z sunday/...
issued at 520 am edt sat oct 17 2026
high pressure builds in with vfr conditions, light winds and
mainly clear skies this weekend into much of next week.
&&
.iwx watches/warnings/advisories...
in...frost advisory until 9 am edt this morning for inz005>009-014-
017-104-116-204-216.
frost advisory from 3 am edt /2 am cdt/ to 9 am edt /8 am cdt/
sunday for inz005-012>015-020-022-103-104-203-204.
freeze warning from 3 am to 9 am edt sunday for inz006>009-017-
018-023>027-032>034-116-216.
oh...freeze warning from 3 am to 9 am edt sunday for ohz001-002-004-
005-015-016-024-025.
mi...frost advisory until 9 am edt this morning for miz078>081.
marine...small craft advisory until 11 am edt this morning for lmz043-
046.
&&
$$
discussion...roller
aviation...steinwedel