846
FXUS63 KIND 191011
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
611 AM EDT Thu Sep 19 2024

.KEY MESSAGES...

- Highs in the upper 80s to low 90s today, low RH values around
  25-30% this afternoon
- Humidity gradually increasing through the rest of the week
- Isolated showers and storms possible late in the day Friday
- Additional rain chances Sunday Afternoon - Wednesday

&&

.SHORT TERM (Today and tonight)...
Issued at 259 AM EDT Thu Sep 19 2024

Quiet weather conditions are expected through the period as upper
ridging and surface high pressure remain centered over the region.
Temperatures have efficiently cooled overnight under good
radiational cooling conditions with most areas in the upper 50s to
low 60s. Look for temperatures to gradually cool through daybreak
though lows should be slightly higher compared to yesterday due
to higher dewpoints.

Current satellite imagery shows scattered high clouds associated
with some upper level moisture moving across the region. These
clouds will clear out shortly after daybreak as upper ridging
gradually builds eastward. Look for efficient daytime heating
promoted by a dry airmass and little cloud cover to warm
temperatures into the upper 80s or low 90s today. Low RH values
around 25-30% are likely again this afternoon due to deep mixing.
Thankfully, light winds should limit fire weather concerns for
the most part despite low humidity. The number of county burn bans
in effect continues to rise for parts of central Indiana so
please exercise caution if burning today.

Expect another quiet night ahead with a large diurnal swing in
temperatures. Good radiational cooling conditions will allow for
temperatures to efficiently cool into the low 60s. Some rural
locations may fall into the upper 50s.

&&

.LONG TERM (Friday through Wednesday)...
Issued at 259 AM EDT Thu Sep 19 2024

Friday through Saturday -

Strong ridging aloft is expected to persist across Central Indiana
on Friday and Saturday. The ongoing very dry air mass across Central
Indiana will continue to dominate our weather as forecast soundings
continue to suggest very strong high pressure in place across the
eastern third of the United States, including Central Indiana. This
will continue to result in similar weather that we have seen for the
past several days, with sunny, hot and dry days and clear mild
nights. Continue to expect highs in the upper 80s to near 90 and
lows in the upper 50s to low 60s.

Sunday through Wednesday -

The upper ridge axis over our region on Friday and Saturday will
shift to the east coast on Sunday. This will allow for a developing
trough over the Rockies to begin to eject forcing dynamics toward
Central Indiana by Sunday afternoon. Meanwhile at the surface, the
previous large surface high is shown to depart as a warm frontal
boundary arrives from the southwest, ahead of an approaching area of
low pressure. As the warm front arrives on Sunday afternoon, models
suggest the arrival of deep saturation. Thus will need to continue
the ongoing pops starting on Sunday afternoon as confidence
continues to grow with the persistent model output. Given the
arrival of clouds and rain, temps on Sunday will not be as warm,
reaching the the lower and middle 80s.

As we progress into Monday through Wednesday, rain chances appear to
continue to persist each day. Models suggest deep troughing
developing over the middle of the United States, with continued
upper forcing streaming across the Ohio Valley from time to time
through Wednesday. Forecast soundings through this period depict
deep saturation from time to time with each passing wave with high
pwats. Meanwhile at the surface low pressure over the middle
Mississippi valley will be providing cyclonic flow across Indiana as
it passed to Michigan on Tuesday and eastern Ontario on Wednesday. A
cold front will also accompany this system and push across Indiana
during the Tuesday-Wednesday time frame. All of these ingredients
are much different than the ongoing weather that we have seen
recently and are favorable for precipitation. Thus pops will be
needed each day, and as with Sunday, confidence continues to grow
for rain. Given the expected clouds and rain, daily high
temperatures are also expected to retreat somewhat towards normals,
with highs in the upper 70s.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 610 AM EDT Thu Sep 19 2024

Impacts:

- None.

 Discussion:

VFR conditions are expected through the period.

A few isolated high, thin clouds will be found across the TAF sites,
however CIGs will remain unlimited. Strong high pressure over the
eastern half of the United States will continue to remain in control
of Indiana/s weather through the period.

Winds will be light and variable for much of the period.

&&

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

$$

SHORT TERM...Melo
LONG TERM...Puma
AVIATION...Puma