993
FXUS63 KIND 062223
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
623 PM EDT Sat Jul 6 2024

.KEY MESSAGES...

- Clear Tonight

- Sunny and warmer Sunday

- Rain chances return late Monday into Tuesday

- Watching Wed into Thu for the remnants of Beryl to produce
  heavy rain and localized flooding in portions of the Ohio Valley

&&

.SHORT TERM (This evening through Sunday)...
Issued at 257 PM EDT Sat Jul 6 2024

Broad surface high pressure from Texas to the Mississippi and Ohio
Valleys and southern Great Lakes along with a dry column per Hi-res
model soundings has provided plenty of sunshine this afternoon with
just some scattered to broken diurnal fair weather cu present on
visible satellite loop and in obs. These clouds will dissipate
around sunset leaving behind clear skies. Afternoon dew points in
the lower to middle 60s will set a reasonable overnight low
temperature forecast tonight as winds go very light to calm in ideal
radiational cooling setup. The boundary layer. Sounds suggest the
boundary layer will be too dry for fog save perhaps some very brief
shallow ground fog toward daybreak.

The surface high will shift to the east on Sunday. However, winds
will be very light southwest with the weak pressure gradient. Again
look for just some scattered diurnal cu Sunday afternoon per the cu
development progs. Mixing and solar heating will allow temperatures
to warm a touch more to the middle to upper 80s. Confidence is good
regarding temperatures to within a couple of degrees. There is a
very small chance that if greater cloud coverage occurs,
temperatures may be a few degrees below forecasted highs.

&&

.LONG TERM (Sunday night through Saturday)...
Issued at 257 PM EDT Sat Jul 6 2024

Broad upper troughing remains over the Upper Midwest and Great Lakes
region through the majority of the period placing Indiana within
southwesterly flow just ahead of the trough axis. Multiple waves
riding around the trough next week in addition to Gulf moisture
directed northeastward into the Ohio Valley will bring daily chances
for showers and storms beginning late Monday. Watching the potential
for flooding midweek as the remnants of Hurricane Beryl are
directed northeastward into the Ohio Valley.

The warmest day of the week will likely occur on Monday as broad
high pressure that had been in place through the early weekend
gradually begins to break down ahead of the next rain producing
system. Plenty of sun combined will allow for temperatures to rise
into the mid to the lower 90s.  With the high pressure nearly
overhead, there will be little relief in terms of a breeze with near
calm winds. There should be at least some diurnal cu during the mid
to late afternoon hours which may provide some relief but with
dewpoints only in the mid 60s, the overall heat threat is minimal.

A broad trough will slowly exit the Central Plains late Monday night
with rain likely late Monday evening through Tuesday. Models are
suggesting a localized area of convergence along a weak cold front
where higher precipitation amounts are likely, but there remains
quite a bit of model spread as to where exactly that settles. Models
have come into better agreement that the higher amounts should
remain to the northwest of the forecast area into northern Illinois,
but will continue to monitor the threat for heavy rain in the coming
days.

Central Indiana and much of the region will remain in a
southwesterly flow pattern aloft with broad troughing just to the
northwest and upper ridging over the Southeast. With a quasi-
stationary front over the Ohio Valley during this time, a constant
feed of tropical moisture will be streaming into the region bringing
daily rainfall chances. The main focus next week will be where the
energy and moisture from Beryl will be directed as this area will
likely see an extended period of potentially heavy rainfall sometime
Wednesday into Thursday. Models have been trending a more northerly
track for the hurricane and a quicker ingestion into the jet stream
which could bring remnant moisture to southern Indiana as early as
Wednesday. This moisture then would combine with the stalled front
to create localized heavy rain with the potential of 2-3 inches of
rain between Wednesday and Thursday. Latest models runs show South
Central Indiana to Northern Kentucky as the area most likely to
receive the heaviest rainfall; however since this event is still
several days away, there is still time for the axis of heaviest
rainfall to shift. All of Central Indiana should pay close attention
to the forecast through the week for any changes regarding the
track, timing, and flooding potential from the remnants of Beryl.

Kept the forecast on a more pessimistic side Tuesday through
Thursday keeping skies cloudier than what guidance suggests and
lowered high temperatures toward the 10th-25th NBM percentile, in
the upper 70s to low 80s. Lowest temperatures will be where heaviest
precipitation is. After coordinating with surrounding NWS offices,
have increased PoPs to likely category Wednesday into Thursday for
areas along and south of I-70. This will likely be tweaked in the
coming days, but for now this a reasonable scenario to put in the
forecast.

Drier and warmer conditions are likely by Friday and into the
weekend; however confidence will remain low on specifics until
guidance gets a better handle for how Beryl and the stalled out
front will evolve in the prior days.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 623 PM EDT Sat Jul 6 2024

Impacts:

- Brief fog possible at outlying terminals near daybreak Sunday

Discussion:

Coverage of diurnal cu is gradually decreasing with all cu likely
dissipating shortly after sunset. The rest of the night will see
mainly clear skies with brief patchy fog possible at KBMG/KHUF/KLAF
predawn through daybreak Sunday.

Return flow will develop on Sunday as the center of the high shifts
east. Expect light S/SW winds during the afternoon with diurnal VFR
cu developing again.

&&

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

&&

$$

SHORT TERM...MK
LONG TERM...CM
AVIATION...Ryan