Trevlac, Indiana Weather Forecast Discussion

163
FXUS63 KIND 131819
AFDIND
Area Forecast Discussion
National Weather Service Indianapolis IN
219 PM EDT Sat Sep 13 2025
.KEY MESSAGES...
- Showers and storms will be possible at times through tonight
- A few storms may produce hail and gusty winds, especially west
- Hot and dry conditions will reestablish Sunday and continue for
  much of the upcoming week
- Dry fuels and low RH values each afternoon next week may lead to
  an elevated fire threat, but light winds should limit overall
  concerns
&&
.SHORT TERM (This evening through Sunday)...
Issued at 219 PM EDT Sat Sep 13 2025
Rest of This Afternoon...
Initial round of showers and isolated storms will continue to weaken
as it moves across the southeastern third of the forecast area.
Meanwhile, scattered to numerous storms have developed upstream
across northern Indiana and northeast Illinois. These will continue
to move southeast into the area this afternoon.
Forcing for these storms is caused by lift over a boundary that
extends from northeast Iowa into western Indiana. Unstable air to
the west across Illinois is feeding these storms.
Thus expect this current round of upstream convection to continue to
move southeast across the area. Will go with scattered to numerous
coverage in these areas with lower coverage PoPs elsewhere. Gusty
winds and hail are possible, with an isolated severe storm not out
of the question, especially closer to the instability west of the
area.
Additional storms may develop upstream of the current storms as
well, so will keep PoPs going even after this next round passes.
Temperatures will be tricky with the rounds of storms. Where
multiple rounds occur readings may stay around 70, while other areas
recover back into the 70s to around 80. Far southwest and southern
areas may remain in the middle to upper 80s.
Tonight...
Higher uncertainty exists with the PoP forecast tonight. The
boundary will remain in the area with some isentropic lift
occurring. There may also be another piece of upper energy rotating
around the ridge just to the west.
Models have been doing poorly with today`s convection and are
inconsistent with their solutions for tonight, so they are no help.
Given the boundary and isentropic lift continuing, will broadbrush
chance PoPs most areas through the night. Later forecasts may be
able to pin down better timing and locations of the PoPs.
Thanks to clouds and higher dewpoints, lows will be mainly in the
60s.
Sunday...
Some weak lift may continue in the southwest early Sunday, but am
not confident enough to introduce PoPs at this time. Otherwise, the
upper ridge will begin to build into the area, and this should put a
stop to any convection from forming.
Clouds will diminish with the ridge moving in, and sunshine will
boost temperatures into the middle 80s to around 90.
&&
.LONG TERM (Sunday night through Saturday)...
Issued at 219 PM EDT Sat Sep 13 2025
An upper level ridge will keep very warm to hot conditions as well
as dry weather across central Indiana into at least mid-week next
week.
At the surface, in general high pressure will be in control, but a
weak surface trough will be in the vicinity. Even with this surface
trough around, subsidence from the upper ridge should keep the area
dry.
Most areas will still have a dry ground, and the atmosphere will
remain relatively dry as well. The combination of the previous will
allow temperatures to get into the upper 80s to lower 90s. This will
help worsen drought conditions.
Models continue to try to break down the ridge before the end of the
work week and then bring an upper level low into the area. As models
are often too fast in breaking down the ridge, confidence is lower
than usual for the timing of this upper low.
Given the uncertainty, will keep with blended guidance bringing in
PoPs for Thursday night into Saturday. Clouds and the upper system
will bring cooler temperatures, with highs falling into the lower 80s
by next Saturday.
&&
.AVIATION (18Z TAF Issuance)...
Issued at 104 PM EDT Sat Sep 13 2025
Impacts:
- Scattered convection this afternoon and again tonight
- Low chance for fog at KLAF overnight
Discussion:
VFR conditions are expected outside of convection through the
period.
First round of weakening convection should be south of most sites by
valid time, with perhaps KBMG still seeing some. However, additional
scattered convection has developed upstream and will move southeast
into the area. Will use VC/TEMPOs for now to cover this and adjust
if necessary.
Very low confidence convection forecast for tonight with guidance no
help. Another round of storms is possible, but location and timing
is hard to pin down (if it even occurs). Will continue with PROB30s
but only mention showers for now.
Some fog may develop at KLAF overnight but confidence is too low to
include.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...50
LONG TERM...50
AVIATION...50

NWS IND Office Area Forecast Discussion