Indiana’s Weather For Friday

HEADLINES
– Clouds and a few sprinkles north and northeast of Indy this afternoon.
– Not as cold as recent temps, but below normal temperatures through the holiday.
– Next chance for general rainfall is Tuesday.

TODAY’S MAP

NWS TECHNICAL DISCUSSION

The region remains under the influence of the pesky double barreled
upper low to our northeast but to a lesser extent than the last few
days as surface high pressure was now present over the region as
well. Despite the clear skies this morning...a thicker area of mid
level clouds was tracking southeast over northern Indiana and will
move across areas to the northeast of the Indy metro into the early
afternoon. In addition...cooler air aloft does support the formation
of scattered diurnal cu by late morning and persisting into the
afternoon.

A trailing surface boundary will slide south into the forecast area
this afternoon but the lack of appreciable moisture within the lower
levels and a noticeable capping inversion in the 600-700mb layer
will likely mitigate any shower development along the boundary.
Could potentially see a few sprinkles over northern counties this
afternoon but uncertainty in this occurring remains far too high for
inclusion into the forecast at this time.

Low level thermals support a range of mid to upper 60s for highs
this afternoon from northeast to southwest. Could see a few spots in
our far northeast counties held in the lower 60s where cloud
coverage is likely to be greatest. Zone and grid updates out.

&&

.SHORT TERM (Today and tonight)...
Issued at 303 AM EDT Fri May 23 2025

Much drier and relatively warmer conditions finally arrive across
Central Indiana after a very cool and wet week. High pressure
dropping south from Canada moves overhead over the next few days,
becoming the dominant weather influence locally. While temperatures
will be almost 10 degrees warmer than the past couple days, highs
remain below average for this time of year.

Early this morning, satellite imagery shows mainly clear skies over
Central Indiana as high pressure advects in much drier airmass.
ACARs soundings do show a shallow nocturnal setting up keeping
any leftover moisture trapped near the surface. With a weakening
pressure gradient, near calm winds, and clear skies, optimal
conditions are setting up for radiational cooling and fog
development. Watching the Wabash River Valley and portions of
South Central Indiana for greatest risk of fog development through
around 8-9 am this morning. Observations already indicate patchy
areas of fog developing with a few locations reporting visibility
down to a mile at times. Expect fog to expand across this area
through the morning hours before quickly dissipating after
sunrise.

Lowered temperatures slightly through the morning hours into the
upper 30s for North Central Indiana and wind sheltered, low lying
areas. Still not expecting frost development though.

For the rest of the day, high pressure will allow for ample sunshine
and surface heating. The Canadian airmass aloft is still quite cool;
however strong surface heating and deep mixing should yield highs
about 10 degrees warmer than yesterday in the mid to upper 60s.

&&

.LONG TERM (Saturday through Thursday)...
Issued at 324 AM EDT Fri May 23 2025

The long term period starts off on a dry and mild note across
Central Indiana; however wet weather returns next week for portions
of the state.

A broad northwest flow pattern remains in place through Sunday while
a surface high from Canada keeps a relatively cool airmass over the
state for the next several days. This will be short lived as a
trailing longwave upper trough extending from the Canadian Maritimes
west into the northern Plains eventually pivots south into the
region by the middle of next week. The pattern setting up into next
week keeps the cooler weather in place while precipitation chances
increase once again. Longer range guidance doesn`t show a
significant warm up back to near normal temperatures until the last
day of May and into early June.

.Saturday and Sunday...

Saturday may be the nicest day of the upcoming extended weekend with
partly sunny skies and mild temperatures in the mid to upper 60s.
Slightly warmer lows expected Saturday night ranging from the mid
40s to lower 50s northeast to southwest as clouds increase from the
west. The increasing clouds are courtesy of subtle waves aloft
riding from the northern Plains within the northwest flow pattern
interacting with low level moisture and a warm front that will
eventually nudge into the lower Ohio Valley by Sunday. Model trends
over the last day or so have been to shift the axis of showers
setting up with this system further to the southwest across the
region, while Central Indiana remains on the cooler, drier side of
the things. While scattered showers will likely be present Sunday
for Southwest portions of Indiana, confidence continues to grow that
the majority of Central Indiana, including the Indy Metro, will
remain dry on Sunday. A cool airmass still remains in place Sunday
and with increasing clouds, highs will likely be stuck in the 60s.

.Next week...

The overall weather pattern begins to shift next week as the upper
jet becomes more west-southwesterly aloft and the storm track lifts
northward into Indiana. Closer to the surface, high pressure begins
to lose its influence over the state as a developing area of low
pressure in the Plains and associated frontal boundaries lift
northward. Low pressure is expected to ride along the warm front
extending over the Ohio Valley and provide perhaps the best
opportunity for more widespread rain and embedded thunderstorms
Monday night through Tuesday. The focus for greatest convective
coverage will again be over southern counties in closest proximity
to the warm front and track of the surface low. By Wednesday,
Indiana will be in the wake of the passing low to the east with
leftover showers and a few storms around.

Confidence decreases mid to late next week and into the following
weekend as a more zonal flow pattern sets up for the middle of the
country with an upper low across the US/Canadian border. Timing
individual waves aloft within the weaker jet aloft is challenging at
this stage. Low level thermals maintain highs in the 60s through
Tuesday with slow improvement into the lower 70s by the tail end of
the 7 day period.

Should the forecast pan out with highs remaining below 70 through
Tuesday here at Indy, this would mark a consecutive string of 8
straight days of sub-70 degree weather extending back to this past
Tuesday 5/20. The last time Indianapolis experienced this for such a
long period of time this late in the Spring was from 5/25 to 6/2 in
1889. The search for a return to more persistent warmth likely is
still 7-8 days out and possibly beyond with 80s likely to return by
early in the week of June 2.

&&

INDY SEVEN DAY FORECAST
Carb Day: Morning sun and afternoon clouds. High 67.

Tonight: Partly cloudy. Low 46.

Parade Day: Mostly sunny morning. Partly sunny afternoon. High 70.

Saturday Night: Partly cloudy. Low 49.

Race Day: Partly sunny. High 68.

Sunday Night: Partly cloudy. Low 49.

Memorial Day: Partly sunny. High 71.

Monday Night: Mostly cloudy. Spotty showers late. Low 55.

Tuesday: Mostly cloudy. Spotty showers. High 69.

Tuesday Night; Mostly cloudy. Low 57.

Wednesday: Mostly cloudy. High 72.

Wednesday Night: Partly cloudy. Low 56.

Thursday: Partly sunny. High 75.

NWS CHARTS FOR TODAY/TONIGHT