Area Forecast Discussion
Issued by NWS Northern Indiana

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749
FXUS63 KIWX 191850
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
250 PM EDT Sat Oct 19 2024

.KEY MESSAGES...

- Scattered showers during the middle of this upcoming week will
  do little to ease the ongoing severe drought over much of the
  area.

- Warming trend will continue into the early parts of the week
  with much above normal temperatures by Monday. The potential
  exists for some 80 degree high temperatures Monday across
  portions of the area.|

&&

.DISCUSSION...
Issued at 249 PM EDT Sat Oct 19 2024

A rather stagnant upper level air pattern will continue through the
weekend, but slow progression in this pattern, namely with the cut
off upper level low across southwest CONUS, will allow a continued
moderation in temperatures into Monday.

For tonight into Sunday, little in the way of weather concerns to
talk about today. Extensive low level anticyclone centered across TN
Valley into the Mid Atlantic states will slowly sink southeast into
Sunday. This will allow for some weak low level height gradient to
become established across the southern Great Lakes tonight. Weak low
level warm advection on western periphery of this anticyclone and
some tightening of low level height gradient should allow for
some moderation in min temps tonight. However, persistent dry
nature to airmass should still allow for lows in the upper 30s
to lower 40s. Favored cool, low-lying locations could make a run
at the mid 30s again, particularly across southeast parts of
the area.

Broad, deep layer subsidence to continue to Sunday which paired with
broad modest westerly flow regime will allow for continued
moderation in low level temperatures. Low level thermal progs would
suggest max temps on the order of 2 to 5 degrees warmer for Sunday
compared to today with highs in the mid 70s.

For Monday, guidance remains consistent in depicting onset of a
little more progression in upper level wave pattern with eventual
northeast ejection of upper low across central high Plains. Upper
ridge axis is expected to reach southern Great Lakes/Ohio River
Valley Monday afternoon with continued moderation of low level
temperatures. Mixing heights still appear somewhat limited to around
900 mb Monday afternoon , but warmer low level temps and potential
of some superadiabats with the dry airmass/ground could support
highs approaching the 80 degree mark. Extent of high temps Monday
will be somewhat dependent on timing of any increased high
cloudiness during the afternoon however.

For Tuesday, attention will turn to evolution of upstream upper low,
with continued indications that this system will continue to
fill/dampen as it makes its way across the southern Great Lakes.
Synoptic ascent should be relatively tempered across the area as
DPVA will be somewhat muted by its vertically stacked nature
and even some isentropic descent. Some slight chance PoPs may
still be in order late Tuesday afternoon/evening during
strongest upper forcing with some mid level moisture return, but
relatively dry subcloud layer and progressive nature of forcing
will not allow this precip chance to amount to much.

For Wednesday-Friday, medium range guidance still suggests
larger scale upper level wave will ride western CONUS upper
ridge and dig across Upper Midwest/Great Lakes region. Some
question still persists regarding duration of any significant
moisture advection ahead of this system, with some concern that
veering of low level flow may cut off better moisture advection
with this forcing. Given moisture questions, and the fact
stronger upper forcing may bypass the area across the Great
Lakes/northeast CONUS, will continue with low to mid range
chance PoPs Wed/Wed evening, especially for northern locations.
Below normal temperatures should build in for Thursday, but
this cooler air will likely be short-lived as a transition back
to less flow amplitude is expected by next weekend.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1248 PM EDT Sat Oct 19 2024

High pressure centered east of the area, will continue to bring
light winds and no flight concerns for the period and beyond.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...None.

&&

$$

DISCUSSION...Marsili
AVIATION...Fisher