Hope, Indiana Weather Forecast Discussion

273
FXUS63 KIND 171900
AFDIND
Area Forecast Discussion
National Weather Service Indianapolis IN
300 PM EDT Wed Sep 17 2025
.KEY MESSAGES...
- Dry and very warm to hot conditions will persist for the rest of
  the work week
- Heat and low RH values each afternoon through Friday may lead to
  a marginally elevated fire threat, but light winds should limit
  overall concerns
- Next chance of rain and slightly cooler temperatures arrives
  for the second half of the weekend into the first half of next week
&&
.SHORT TERM (This evening through Thursday)...
Issued at 300 PM EDT Wed Sep 17 2025
Rinse (or rather, don`t) and repeat remain the name of the game
across central Indiana today into Thursday and late week.
The persistent block will continue to bring the area stagnant air,
above normal temperatures, light winds, and dry weather, making air
quality and to a lesser extent fire weather the primary concerns, as
we lean heavily into persistence for the forecast.
Temperatures across central Indiana this afternoon range from the
mid 80s to around 90, with another degree or two of climb possible
in the next few of hours before the onset of diurnal cooling.
Despite the light winds, what little breeze there is will continue
to keep dewpoints a bit lower than guidance, and this along with the
mostly clear skies and winds going calm across much of the area
tonight will set up ideal radiational cooling conditions,
particularly with the dry ground.
Lows should drop into the upper 50s across most of the area save for
the far southwest and urban heat island impacted areas of Indy,
which will likely remain in the lower 60s. Rural and low-lying,
climatologically-favored areas may see brief and patchy light fog
just prior to daybreak, as occurred this morning.
A very similar day to today is expected tomorrow with hot
temperatures, low humidity, and light winds. Thicknesses suggest
highs a degree or two above today`s, in the upper 80s to low 90s.
Our partners at the Indiana Department of Environmental Management
and the City of Indianapolis have extended air quality action
notices into tomorrow, and have concurrently relayed this
information via the Air Quality Alert product.
Afternoon RH values will be in the 25 to 35 percent range again
tomorrow, which along with persistent dry conditions does raise
marginal fire weather concerns, but the very light winds and
abundance of still herbaceous fuels per partners will heavily
mitigate the danger of fire spread.
&&
.LONG TERM (Thursday night through Wednesday)...
Issued at 300 PM EDT Wed Sep 17 2025
The persistent Omega blocking pattern over the area keeping us
summer-like and dry in recent days will continue to be the dominant
force over the area through at least the end of the work week,
gradually beginning to shift orientation and then break down later
this week and into the weekend. This process will allow for
moderation of temperatures back to near seasonal normals later this
weekend into early next week, as well as at least low chances for
some scattered showers and perhaps isolated thunderstorms at times
as early as Friday night onward.
Guidance has continued to slowly but steadily trend slower with the
demise of the block, which is fairly typical of both blocking
patterns and NWP`s handling of them, so uncertainty is a bit higher
than desired, even for the long range, with respect to precipitation
chances, particularly over the weekend, but at least low PoPs are
merited.
As the block erodes, a couple of upper level lows will eventually
push eastward and exert influence on the region over the weekend
into next week, again allowing for moderation of temperatures and
potential for rainfall.
Abnormally dry or moderate drought antecedent conditions over the
area, along with surface high pressure at least partially inhibiting
moisture return from the Gulf, additionally add uncertainty to the
rain potential. The old maxim of "drought begets drought" may be in
play. GFS Integrated Water Vapor Transport progs (IVT) are quite
poor to non-existent through at least Saturday evening, but
gradually improve with time, particularly by late Sunday onward,
though moisture transport is maximized just to our west/northwest.
Significant uncertainty will remain through the end of the period
and beyond as global models begin to differ significantly toward the
end of the forecast period on the timing and position of the second
upper level low, which will have significant impacts upon both the
degree of cooldown and PoPs/persistence of precipitation chances.
&&
.AVIATION (18Z TAF Issuance)...
Issued at 119 PM EDT Wed Sep 17 2025
Impacts:
- Brief MVFR fog possible at the outlying sites between 10-13Z
  tonight.
Discussion:
VFR conditions are expected to continue across the region through
Thursday morning, with the possible exception of brief pre-sunrise
fog at the outlying sites, as occurred this morning at LAF/HUF.
With a stagnant pattern and no change in airmass have leaned heavily
upon persistence. Thus, light and variable winds much of the time,
going calm at most sites overnight, little to no cloud cover aside
from a very few diurnal cumulus, and TEMPO groups for MVFR fog at
the outlying sites just prior to daybreak.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Nield
LONG TERM...Nield
AVIATION...Nield

NWS IND Office Area Forecast Discussion