Plymouth, Indiana Weather Forecast Discussion

424
FXUS63 KIWX 161805
AFDIWX
Area Forecast Discussion
National Weather Service Northern Indiana
205 PM EDT Tue Sep 16 2025
.KEY MESSAGES...
- Remaining warm and dry through Friday with highs in the mid to
  upper 80s.
- Rain shower chances (20-40%) arrive this weekend into early
  next week.
&&
.DISCUSSION...
Issued at 205 PM EDT Tue Sep 16 2025
Expansive upper level ridge to gradually shrink overhead through the
remainder of the week as northern stream shortwave energy through
Ontario/Quebec eventually absorbs a Mid-Atlantic closed low up the
East Coast. The dry and stable column under this upper ridge will
continue to ensure more warm and dry weather locally through Friday.
Some weak moisture flux off Lake Erie in weak easterly flow may once
again support patchy fog/stratus formation toward daybreak along and
east of the Ohio border early Wednesday morning.
The ridge breaks down this weekend into early next week as an upper
trough approaches from the Central US and moisture attempts to
stream northward pre-frontal. This will bring periodic/low
shower chances (20-40%), and non-zero chances for an isolated
storm, back into the fold during this time, with mean ensemble
solutions favoring Sunday into Monday for slightly better rain
prospects (mainly light).
&&
.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1225 PM EDT Tue Sep 16 2025
High pressure should allow VFR conditions to dominate both sites
through the period. As mentioned in the 12Z TAF discussion, a
few models hint as some shallow fog in the typical 9 to 12Z time
frame (inversion it at its strongest), mainly at KFWA. While an
argument could be made to introduce a brief tempo group, not
enough confidence to cause flight impacts quite yet, so will
defer to the 00Z or possibly 06Z TAF issuance for possible
addition.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...None.
&&
$$
DISCUSSION...Steinwedel
AVIATION...Fisher

NWS IWX Office Area Forecast Discussion