514
fxus63 kiwx 171120
afdiwx
area forecast discussion
national weather service northern indiana
620 am est tue feb 17 2026
.key messages...
- above normal temperatures with highs in the 50s and 60s
through thursday.
- rain showers are likely tonight into wednesday morning, and
again thursday into thursday night.
- cooler by this weekend with chances for rain and snow showers.
&&
.discussion...
issued at 212 am est tue feb 17 2026
slightly stronger southerly flow on the backside of sfc high
pressure, and areas of mid-high clouds in a broad waa regime,
should reduce the fog threat for most this morning when compared
to yesterday. another mild/dry day otherwise today as shortwave
ridging overspreads in advance of an upper trough and sfc low
lifting northeast into the upper midwest and western great lakes
tonight into wednesday. a relatively deep corridor of moist
isentropic ascent will precede this wave under the left exit
region of an incoming ~160 kt upper jet later this evening
through wednesday morning. better low level convergence near a
developing frontal zone primarily sets up just north of the
area, though still expect at least scattered/numerous showers
given the sufficient moisture advection and incoming steeper mid
level lapse rates. rainfall amounts should overall remain on
the light side (<0.20", heaviest north), though localized
heavier amounts cannot be ruled out in any gusty convective
elements wed am. dry slot and associated warm sector should
become well established then by wed pm with breezy/mild
conditions (near record high temps) behind a dry line type
feature.
additional chances for rain and perhaps some thunder will increase
thursday into thursday night as a secondary shortwave emerges out of
the rockies and rotates a deepening sfc low northward into the
western and northern great lakes. a colder, more seasonable, air
mass will then rotate in behind this system later friday into the
weekend. several shortwaves will also rotate through in this colder
cyclonic flow with periodic chances for snow showers.
&&
.aviation /12z tafs through 12z wednesday/...
issued at 620 am est tue feb 17 2026
mid level clouds and a modest low level height gradient have
helped prevent widespread fog formation across northern indiana
this morning. patchy fog has been most prevalent east of kfwa
into northwest ohio and extreme northeast indiana where mid
level clouds thinned faster and allowed for a period of better
radiational cooling. with broad warm advection increasing this
morning, near sfc dew point depressions should remain large
enough to prevent significant fog concerns this morning. cannot
completely discount some brief mvfr vsby restriction potential
in the 12z-14z timeframe, but confidence in inclusion as far as
tempo mention is diminishing.
otherwise, stalling low level cold front north of terminals
will lose its integrity today with overall weak flow and poor
mixing for the terminals. light south winds will strengthen
tonight as deep low pressure shifts across eastern south
dakota/northwest iowa. a downstream low level jet will allow for
more notable low level moisture advection into the region
tonight. this setup appears marginal in terms of meeting llws
criteria, so will refrain from mention at this longer forecast
distance. this increased moisture, upper level diffluence, and
favorable jet dynamics should allow for blossoming rain to
affect terminals late in the period tonight. some weak elevated
instability could yield an iso thunder potential, particularly
at ksbn, but point probabilities remain too low for inclusion
with the 12z tafs. conditions should deteriorate to mvfr late
evening into early wednesday morning, with a potential of some
ifr cigs late tonight/early wednesday at ksbn.
&&
.iwx watches/warnings/advisories...
in...none.
oh...none.
mi...none.
marine...none.
&&
$$
discussion...steinwedel
aviation...marsili