246
FXUS63 KIND 270111
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
911 PM EDT Wed Mar 26 2025

.KEY MESSAGES...

- An isolated shower possible, mild with highs in the 50s

- Near normal temperatures through Thursday, unseasonably warm
  Friday-Sunday with highs into the 70s then turning cooler early next
  week

- Wet and unsettled pattern developing with periodic rain and storm
  chances Thursday through Monday

- Strong to severe storms possible Sunday afternoon and evening

&&

.FORECAST UPDATE...
Issued at 910 PM EDT Wed Mar 26 2025

Surface analysis late this evening shows a large area of high
pressure stretching from KY and TN across Indiana to the Great
Lakes. Northwest flow was in place aloft. GOES16 shows a leaf of mid
and high cloud within upper flow over WI and MN, aiming at Indiana.
Lower level winds were from the west as the surface high was
drifting east, but dew points across the area remained very dry, in
the upper 20s and lower 30s. Radar imagery that has shown echos that
were present earlier and only producing some trace amounts of rain
have decreased in coverage and pushed east.

Models suggest the surface high will continue to drift southeast
overnight, while the mid and high clouds upstream invade through the
night. Forecast soundings show the arrival of these clouds via mid
level saturation, but dry air remains within the lower levels. Warm
air advection is in play overnight along with the arrival of the
high clouds. These features will prevent max radiational cooling.
Thus the ongoing low temps in the middle to upper 30s will be on
target along with the skies becoming mostly cloudy overnight.

&&

.SHORT TERM (This evening through Thursday)...
Issued at 256 PM EDT Wed Mar 26 2025

Northwesterly flow continues aloft with occasional upper-level waves
passing through. These waves, in conjunction with an approaching
warm front from the southwest, will lead to scattered showers and
possibly thunderstorms at times through Thursday night.

Isolated showers this morning have already exited the area, and we
remain between upper waves. Enough shallow instability exists for a
few widely scattered showers this afternoon as the cumulus field
matures. Any activity that develops should diminish around sunset.

Rain chances increase further late tonight as the warm front nears.
Guidance tends to initiate showers and storms upstream during the
overnight hours tonight and also Thursday night. This appears to be
coincident with the development of a nocturnal low-level jet, which
will aid lift and moisture transport. Upstream activity then drifts
south and east with time bringing scattered showers into most of our
area through the remainder of the forecast period.

As for temperatures, we`ll likely be warmer tonight compared to last
night due to the presence of cloud cover. Still, lows should drop
into the 30s at times with possible frost.

Highs on Thursday may be lower than today, however, also due to
cloud cover and scattered rain showers. Most locations should climb
into the low to mid 50s, though some members of guidance hint at a
few spots not even reaching 50.

&&

.LONG TERM (Thursday night through Wednesday)...
Issued at 256 PM EDT Wed Mar 26 2025

Thursday Night Through Saturday.

The shift to a more active pattern continues into Thursday night
with the next round of more widespread showers and thunderstorms.
There looks to be a brief break during the early overnight after the
evening round of storms with the next round late Thursday night into
early Friday. The near surface will be nearly isothermal with a
nearly saturated sounding which would limit the instability and
limit the severe wind threat. There may be a narrow swath of
precipitation of an inch or more, but there remains a fair amount of
model spread as to where this swath would occur. The warmest day of
the period is expected for Friday with highs in the mid 70s as
precipitation comes to an end while strong southerly flow advects
much warmer than normal air into the area. Dry conditions should
continue into Friday night with the next round of showers and storms
late Saturday into Saturday night. Another warm day is expected for
Saturday but with increasing clouds, only expect highs to top out
around 70. Total QPF with this low pressure system may be as high as
an inch but exact details are fairly uncertain.

Sunday Through Wednesday.

A much stronger synoptically driven low pressure system is expected
late Sunday into Sunday night with the potential for strong to
severe storms to impact central Indiana with higher confidence in
impacts across the Ohio Valley in general. Global models and their
associated ensembles show decent agreement in the broader trough and
associated cold front with differences on both the strength and
timing of the low pressure system. Thus there is high confidence in
precipitation with lower confidence in timing and intensity of the
associated thunderstorms. Colder air will move in behind the exiting
low Sunday night with sub-freezing temperatures likely for at least
part of the forecast area Monday night. Dry weather with northerly
surface flow will then continue through Tuesday with a shift to
easterly flow towards Wednesday as rain chances begin to increase
although the overall synoptic pattern is highly uncertain.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 703 PM EDT Wed Mar 26 2025

Impacts:

- MVFR is expected this period.

Discussion:

Surface high pressure over Indiana is expected to push east to the
Carolinas tonight and Thursday. The high will allow for light winds
across the TAF sites tonight with southerly flow developing on
Thursday.

GOES16 shows mid level clouds upstream of Indiana. These should
arrive overnight, leading to VFR Cigs. Forecast soundings show this
mid level saturation persisting through much of the overnight hours
and into Thursday. By Thursday afternoon, HRRR suggests scattered
shower development within the NW flow aloft. For now, have included
a VCSH mention for this as lower level organization is weak and
instability appears limited.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

UPDATE...Puma
SHORT TERM...Eckhoff
LONG TERM...White
AVIATION...Puma