349
FXUS63 KIND 312221
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
621 PM EDT Fri May 31 2024

.KEY MESSAGES...

- Showers and isolated thunderstorms Saturday

- Warming trend going into next week with periodic storm chances

- Long range 8-14 day outlook trending toward below normal
temperatures

&&

.SHORT TERM (This evening through Saturday)...
Issued at 251 PM EDT Fri May 31 2024

Early this afternoon, upper air data and satellite was depicting a
high amplitude ridge from Hudson Bay to the Tennessee Valley.
Meanwhile, at the surface, broad high pressure was found over the
eastern Great Lakes and upper Ohio Valley and broad low pressure was
over the Southwest. Satellite was showing only some high clouds
overhead. Southeast winds, filtered sunshine and subsidence has
allowed temperatures to climb to the middle and upper 70s.

Hi-Res soundings were showing a very dry column in place. Meanwhile,
305K isentropic analysis is introducing strong upglide overnight and
into Saturday. Although it will take awhile for the atmosphere to
saturate down, eventually low condensation pressure deficits support
rain chances starting up after 06z. More than likely due to the dry
column in place, it will be more like after 09z and starting over
southwestern sections. Soundings later Saturday morning support
widespread rain which will continue through the afternoon.
Instability progs are showing very weak to no instability, so
lightning strikes should be few and far between.

Warm advection and increasing cloud cover suggest overnight lows
will only be in the upper 50s to lower 60s. Meanwhile, the thick
cloud cover and rain will likely limit temperatures to the lower
70s Saturday afternoon.

&&

.LONG TERM (Saturday night through Friday)...
Issued at 251 PM EDT Fri May 31 2024

Saturday Night Through Sunday.

By Saturday night the surface low will be moving across the northern
half of the state with precipitation expected to continue through
much of the night but the bulk of the forcing will be just ahead of
the low associated with the strengthening LLJ rain coverage and
intensity should decrease through the night. Some precipitation will
likely continue into the daytime hours on the backend of the system
but with the low being more broad and not quite as strong, the flow
on the backend isn`t quite as robust as we saw earlier in the week.
The low stratus clouds will begin to dissipate by the early
afternoon with residual cu persisting through the late evening hours.

Monday Through Friday.

Forecast confidence quickly begins to fall off next week as the flow
aloft becomes much more stagnant and the pattern becomes more driven
by mesoscale factors that are very uncertain this far out. There
does look to be at least occasional showers and thunderstorms which
will generally be diurnally driven so will focus POPs highest in the
18Z to 00Z timeframe.  Surface flow will generally remain southerly
through the week which will keep temperatures just above normal with
much higher dewpoints of mid to upper 60s. A more deeply wrapped up
low looks likely towards the end of the week which should bring a
relief from the more humid air and warmth. The pattern favors the
potential for a few storm complexes across the Midwest but there is
low confidence that any will impact central Indiana.

Going into the latter portions of the week confidence is increasing
in colder temperatures moving back in with a strong upper level low
across the Great Lakes region bringing northwesterly flow at the
surface and aloft with lower confidence on the track and strength of
the low.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 621 PM EDT Fri May 31 2024

Impacts:

- Rain developing Saturday morning

- IFR conditions by mid to late Saturday afternoon

- Small risk for embedded thunderstorms

Discussion:

Cirrus continues to steadily overspread central Indiana ahead of low
pressure moving into the Ozarks this evening. Clouds will continue
to thicken and lower overnight but dry air will remain prevalent
through the boundary layer courtesy of southeast flow. A few light
showers may make it to KHUF near daybreak but most rain will hold
off until later in the morning.

The surface low will track into the lower Ohio Valley on Saturday
with a progressively deeper surge of moisture advecting into the
region from the south. Showers will spread east through the mid and
late morning with widespread rain for the afternoon and evening.
MOdel soundings and RH progs show lower levels becoming saturated
late day with ceilings likely to dip quickly to MVFR and eventually
IFR within the steadier rainfall. Cannot rule out a few rumbles of
thunder but overall instability is minimal and will not mention at
the terminals. Winds will remain southeast through much of the
forecast period and may become sporadically gusty Saturday afternoon
as the surface wave approaches.

&&

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

&&

$$

SHORT TERM...MK
LONG TERM...White
AVIATION...Ryan