129
FXUS63 KIND 200954
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
554 AM EDT Sat Jul 20 2024

.KEY MESSAGES...

- Dry and pleasant this weekend

- Seasonable warmth and increasing humidity returns by late this
  weekend

- Chances for rain/t-storms and increasing clouds next week may help
  keep temperatures slightly below normal

&&

.SHORT TERM (Today and Tonight)...
Issued at 300 AM EDT Sat Jul 20 2024

Mainly clear skies present over central Indiana early this morning
with just a few small pockets with clouds. With light N/NE winds...
06Z temperatures were predominantly in the upper 50s and lower 60s.

The high pressure ridge extending from the Great Lakes back
southwest into the Ozarks will remain as the prominent feature
influencing weather across the region through tonight. Cloud
coverage will increase however...especially late tonight as deeper
moisture advects into the Ohio Valley from the west.

Localized stratocu will linger across the Wabash Valley especially
through daybreak as low level moisture to our southwest gets pulled
north. This should limit most if not all fog potential towards
sunrise although yet again the Wabash Valley is the favored location
with higher dewpoints. Winds within the boundary layer will veer
through the morning that will shut down the moisture at 850mb
advecting north currently. That combined with broad mid level
subsidence will limit overall cloud coverage through the afternoon
with diurnal cu again developing during peak heating. Surface winds
will remain light from the north and northeast as the forecast area
sits on the south flank of the surface ridge.

Mid and high level clouds will gradually increase from the west
overnight as moisture pools within a weak and poorly organized upper
wave moving out of the central Plains. Northerly flow in the low
levels and lingering subsidence noted within the 800-600mb layer
will mitigate any concerns for precipitation through much of the
rest of the weekend...but the arrival of moisture aloft will lead to
increased cloud coverage for Sunday and a subtle increase in
humidity levels.

Temps...low level thermals support a seasonable day with highs in
the low to mid 80s for the forecast area. Dewpoints will remain in
the 50s again today keeping the airmass comfortable. Lows tonight
will be a bit warmer in the low and mid 60s as the airmass further
modifies and clouds increase.

&&

.LONG TERM (Sunday through Friday)...
Issued at 300 AM EDT Sat Jul 20 2024

Most guidance shows upper ridging remaining dominant across the
western CONUS during the extended period with troughing further
east. Initially at the surface, high pressure centered over the
region will continue to provide dry conditions on Sunday. A
noticeable increase in mid-high clouds is likely due to an
approaching upper low. Precipitation is not expected during the day
because forecast soundings show considerable dry air in the low-mid
levels. Gradual saturation of the column may be sufficient for a few
light sprinkles. Despite increasing clouds, deep mixing will allow
for highs to return to near seasonal by the end of the weekend.

Weakening high pressure heading into the start of the work week will
allow for deeper moisture to begin returning northward. Expect
increasing humidity and chances for precipitation as a result. The
main uncertainty for rain chances lies in how much forcing will be
present next week. A weakening upper low is likely going to be
centered near the area. This combined with moisture advection ands
daytime heating could support scattered convection on Monday.

There is a better signal in guidance for stronger synoptic forcing
from another upper wave Tuesday-Wednesday. This combined with
continued moisture advection supports greater rain chances during
this timeframe. Diurnal heating of an anomalously moist environment
should help provide greater coverage of convection during peak
heating, especially Monday when upper level forcing is very weak.
Models begin to diverge late week though the pattern could remain
unsettled with moisture still in place and the potential for
additional disturbances to move through. Temperatures are expected
to be near or slightly below normal next week.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 554 AM EDT Sat Jul 20 2024

Impacts

- No impacts

Discussion:

Small pockets of stratocu continue to drift across the region this
morning as low level moisture is drawn north from the lower Ohio
Valley. By midday...diurnal cu will develop and linger through the
afternoon before diminishing near or just after sunset. Overnight...
mid and high level clouds will overspread the region.

Winds will remain less than 10kts from the N/NE then become light
again tonight.

&&

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

&&

$$

SHORT TERM...Ryan
LONG TERM...Melo
AVIATION...Ryan